WO2019172438A1 - Composite sheet for forming protective film and method for producing semiconductor chip with protective film - Google Patents

Abstract

A composite sheet (1) for forming a protective film, which sequentially comprises a base material (11), an adhesive layer (12) and a film (13) for forming a thermosetting protective film in this order, and wherein the adhesive layer (12) has a storage elastic modulus at 70°C (G'(70)) of 0.16 MPa or less and a storage elastic modulus at 23°C (G'(23)) of 0.10 MPa or more.

Description

Composite sheet for forming protective film and method for manufacturing semiconductor chip with protective film

The present invention relates to a protective film-forming composite sheet and a method of manufacturing a semiconductor chip with a protective film.
This application claims priority based on Japanese Patent Application No. 2018-043566 for which it applied to Japan on March 9, 2018, and uses the content here.

In recent years, a semiconductor device using a mounting method called a so-called face-down method has been manufactured. In the face-down method, a semiconductor chip having electrodes such as bumps on a circuit surface is used, and the electrodes are bonded to a substrate. For this reason, the back surface opposite to the circuit surface of the semiconductor chip may be exposed.

A resin film containing an organic material is formed as a protective film on the exposed back surface of the semiconductor chip, and may be taken into the semiconductor device as a semiconductor chip with a protective film.
The protective film is used to prevent cracks from occurring in the semiconductor chip after the dicing process or packaging.

In order to form such a protective film, for example, a support sheet having an adhesive layer on a substrate, and a protective film forming film for forming a protective film provided on the adhesive layer A composite sheet for forming a protective film is used. In the protective film forming composite sheet, the protective film forming film can form a protective film by curing, and the support sheet can be used as a dicing sheet, and the protective film forming film and the dicing sheet are integrated. It is possible to obtain a composite sheet for forming a resin film (see Patent Document 1). In the manufacturing method of the semiconductor chip using the composite sheet for resin film formation, since the semiconductor wafer is simultaneously attached to the protective film formation film and the dicing sheet, the number of steps can be reduced as compared with the conventional method in which these are performed separately, Cost can be reduced. As a method of dividing the semiconductor wafer together with the protective film, a method of dicing the semiconductor wafer using a dicing blade is widely used.

On the other hand, in recent years, various methods for dividing a semiconductor wafer without using a dicing blade have been studied. For example, a laser beam is irradiated so as to focus on a focal point set inside the semiconductor wafer to form a modified layer inside the semiconductor wafer, and then this modified layer is formed and a resin is formed on the back surface. By expanding the semiconductor wafer with the film attached together with the resin film in the plane direction of the resin film, cleaving the resin film, dividing the semiconductor wafer at the site of the modified layer, and dividing into pieces, A method for obtaining a semiconductor chip is known. If the expansion in the planar direction of the resin film is performed at room temperature of 15 to 25 ° C., there is a risk that the resin film may be poorly divided. Cool expanding under a low temperature condition of −15 ° C. has been studied.

Unlike the method using a dicing blade, the division method using the cool expand does not involve the formation of a cutting portion by the dicing blade in the semiconductor wafer, and more semiconductor chips can be obtained from the semiconductor wafer, and no cutting waste is generated. Has the advantage. There is a film adhesive for die bonding of semiconductor chips to the circuit forming surface of a substrate, but the above dividing method has so far been a composite for resin film formation using this film adhesive as the resin film. In the case of a sheet, it has been mainly used (see Patent Documents 2 and 3).

When the composite sheet for resin film formation is cool expanded in the plane direction, the interval between the semiconductor chips is expanded, and the semiconductor chips can be picked up more easily. At this time, a deviation occurs between the resin film-forming film and the support sheet, the adhesive force between the resin film-forming film and the support sheet is reduced, and the pick-up suitability of the semiconductor chip is improved. It is also known that when a semiconductor chip is picked up in this way, the cleaved resin film forming film can be fixedly left on the back surface of the semiconductor chip and peeled off from the support sheet (see Patent Document 1).

Therefore, such a method can be applied to a semiconductor wafer provided with a film for forming a curable protective film or a protective film that is a cured product thereof as the resin film, as long as the above dividing method by cool expand can be applied. It is extremely useful as a method for manufacturing a semiconductor chip provided with a protective film.

JP 2016-027655 A JP 2012-222002 A JP 2017-183705 A

However, in the manufacture of semiconductor chips, when the protective film-forming composite sheet that meets the pickup suitability is expanded in the plane direction, the distance between the semiconductor chips is expanded, and a shift occurs between the protective film-forming film and the support sheet. The end portion of the semiconductor chip is momentarily peeled off, leaving a mark at the boundary between the peeled portion and the non-peeled portion (sometimes referred to as a “floating mark” in this specification), and the design properties are lowered. Further, after the semiconductor wafer is divided, the chip and the protective film are inspected visually or by an infrared laser, but there is a possibility that the floating mark may hinder the inspection efficiency.

Therefore, the present invention applies a dividing method by cool expanding at a temperature lower than normal temperature, and produces a protective-coated semiconductor chip using a film for forming a curable protective film. Protective film forming composite sheet capable of satisfactorily picking up a semiconductor chip with a protective film, and a semiconductor film with a protective film using the same An object is to provide a method for manufacturing a chip.

As a result of intensive studies by the present inventors in order to solve the above problems, the storage elastic modulus (G ′ (70)) at 70 ° C. of the pressure-sensitive adhesive layer of the composite sheet for forming a protective film is not more than a predetermined value. And having a storage elastic modulus (G ′ (23)) at 23 ° C. equal to or higher than a predetermined value, and using a thermosetting film as a protective film-forming film, it is adhesive after being cool expanded. The adhesive layer and the thermosetting protective film-forming film are partially peeled off, resulting in floating marks, but the elastic modulus of the pressure-sensitive adhesive layer decreases in the subsequent heat-curing process, and the adhesive layer and the protective film It has been found that, by re-adhering, the floating marks can be eliminated, the semiconductor chip with a protective film can be picked up well, and the object can be achieved.

That is, the present invention is as follows.
[1] A substrate, a pressure-sensitive adhesive layer, and a thermosetting protective film-forming film are provided in this order,
A protective film having a storage elastic modulus (G ′ (70)) at 70 ° C. of 0.16 MPa or less and a storage elastic modulus (G ′ (23)) at 23 ° C. of 0.10 MPa or more of the pressure-sensitive adhesive layer. Composite sheet for forming.
[2] The protective sheet-forming composite sheet according to [1], wherein the pressure-sensitive adhesive layer has a storage elastic modulus (G ′ (70)) at 70 ° C. of 0.01 MPa or more.
[3] The composite sheet for protective film formation according to [1] or [2], wherein the pressure-sensitive adhesive layer has a storage elastic modulus (G ′ (23)) at 23 ° C. of 0.45 MPa or less.
[4] The composite sheet for forming a protective film according to [3], wherein the pressure-sensitive adhesive layer is non-energy ray curable or energy ray curable.
[5] The composite sheet for forming a protective film according to [3] or [4], wherein the pressure-sensitive adhesive layer has a thickness of 3 to 20 μm.

[6] A step of laminating a semiconductor wafer on the thermosetting protective film-forming film side of the protective film-forming composite sheet according to any one of [1] to [5]; ,
Irradiating a semiconductor wafer with laser light to form a modified layer inside the semiconductor wafer; and
Cool expanding the laminate at a temperature lower than room temperature, and dividing the semiconductor wafer and the thermosetting protective film forming film,
A process for producing a semiconductor chip with a protective film, comprising: heating and curing the thermosetting protective film-forming film of the laminate to form a protective film.

According to the present invention, when a semiconductor chip with a protective film is produced using a thermosetting protective film-forming film by applying a dividing method by cool expand at a temperature lower than room temperature, the adhesion generated after the cool expansion is performed. Protective film-forming composite sheet that can eliminate the residual trace between the agent layer and the thermosetting protective film-forming film and that can satisfactorily pick up the semiconductor chip with the protective film, and the same A method of manufacturing a semiconductor chip with a protective film is provided.

It is sectional drawing which shows typically one Embodiment of the composite sheet for protective film formation which concerns on this invention. It is sectional drawing which shows typically other embodiment of the composite sheet for protective film formation which concerns on this invention. It is sectional drawing which shows typically an example of the manufacturing method of the semiconductor chip with a protective film. (A) It is a microscope picture of the unhardened semiconductor chip with a film for protective film formation after a cool expansion. (B) It is a microscope picture of the semiconductor chip with a protective film after thermosetting.

◎ Composite sheet for protective film formation The composite sheet for protective film formation of the present invention comprises a base material, an adhesive layer, and a film for forming a thermosetting protective film in this order. The storage elastic modulus (G ′ (70)) is 0.16 MPa or less, and the storage elastic modulus (G ′ (23)) at 23 ° C. is 0.10 MPa or more.

In the composite sheet for forming a protective film of the present invention, the storage elastic modulus (G ′ (70)) at 70 ° C. of the pressure-sensitive adhesive layer is 0.16 MPa or less, preferably 0.15 MPa or less, preferably 0.10 MPa. Or less, more preferably 0.06 MPa or less. The portion between the pressure-sensitive adhesive layer and the thermosetting protective film-forming film that is produced after cool-expanding at a temperature lower than room temperature when the storage elastic modulus (G ′ (70)) is equal to or less than the upper limit. Peeling easily disappears by lowering the elastic modulus of the pressure-sensitive adhesive layer under the conditions of the subsequent thermosetting, and it is possible to leave no floating marks. The storage elastic modulus (G ′ (23)) at 23 ° C. of the pressure-sensitive adhesive layer is 0.10 MPa or more, preferably 0.15 MPa or more, more preferably 0.20 MPa or more, and 0.25 MPa. The above is particularly preferable. When the storage elastic modulus (G ′ (23)) is equal to or higher than the lower limit value, the semiconductor chip with a protective film is too close to the pressure-sensitive adhesive layer after the thermosetting protective film-forming film is thermally cured. Therefore, the semiconductor chip with a protective film can be picked up satisfactorily.

The composite sheet for forming a protective film of the present invention has a storage elastic modulus (G ′ (70)) at 70 ° C. of 0.degree. C. so that the pressure-sensitive adhesive layer is too soft and does not protrude from the end during thermosetting. The pressure is more preferably 01 MPa or more, and particularly preferably 0.02 MPa or more.
That is, the storage elastic modulus (G ′ (70)) at 70 ° C. of the pressure-sensitive adhesive layer is 0.16 MPa or less, preferably 0.01 MPa or more and 0.16 MPa or less, more preferably 0.01 MPa or more and 0.15 MPa or less. Preferably, 0.01 MPa or more and 0.10 MPa or less are more preferable, 0.01 MPa or more and 0.06 MPa or less are particularly preferable, and 0.02 MPa or more and 0.06 MPa or less are most preferable.
In addition, the adhesion between the adhesive layer of the protective film-forming composite sheet and the thermosetting protective film-forming film can be secured, and when the semiconductor chip with a protective film is picked up, The storage elastic modulus (G ′ (23)) at 23 ° C. of the pressure-sensitive adhesive layer is 1.0 MPa or less so that the pickup is suppressed, the chip scattering is prevented, and the target semiconductor chip with a protective film can be picked up with high selectivity. Is preferable, 0.7 MPa or less is more preferable, and 0.4 MPa or less is particularly preferable.
That is, the storage elastic modulus (G ′ (23)) at 23 ° C. of the pressure-sensitive adhesive layer is 0.10 MPa or more, preferably 0.10 MPa or more and 1.0 MPa or less, more preferably 0.15 MPa or more and 0.7 MPa or less. 0.20 MPa to 0.4 MPa is more preferable, and 0.25 MPa to 0.4 MPa is particularly preferable.

In this specification, “thermosetting protective film forming film” means a film before thermosetting, and “protective film” means a film obtained by curing a thermosetting protective film forming film. To do.
In the present specification, what is formed by laminating at least the base material and the pressure-sensitive adhesive layer may be referred to as a “support sheet”.

Further, in the present specification, even after the thermosetting protective film-forming film is thermally cured, the cured product of the base material, the pressure-sensitive adhesive layer, and the thermosetting protective film-forming film (in other words, the support As long as the laminated structure of the sheet and the protective film is maintained, this laminated structure is referred to as a “protective film forming composite sheet”.

In the present specification, “normal temperature” means a temperature that is not particularly cooled or heated, that is, a normal temperature, and examples thereof include a temperature of 15 to 25 ° C.
In this specification, “cool expand” refers to applying a force that expands in a direction parallel to the surface of a semiconductor wafer at a temperature lower than room temperature (eg, −20 to 10 ° C.).
In this specification, the “storage modulus” is a tensile mode, a frequency of 11 Hz, a temperature rising rate of 3 ° C./min, using a dynamic viscoelasticity measuring device as a sample of a 200 μm thick adhesive layer. A value measured under the measurement conditions of a measurement temperature range of −20 ° C. to 150 ° C. and a measurement interval of 1 ° C.

FIG. 1 is a cross-sectional view schematically showing one embodiment of a composite sheet for forming a protective film according to the present invention.
The protective film-forming composite sheet 1 shown here includes a base material 11, an adhesive layer 12, and a thermosetting protective film-forming film 13 in this order. The storage elastic modulus (G ′ (70)) at 70 ° C. of the pressure-sensitive adhesive layer 12 is 0.16 MPa or less, and the storage elastic modulus (G ′ (23)) at 23 ° C. is 0.10 MPa or more. The protective film-forming composite sheet 1 further includes a release film 15 on the thermosetting protective film-forming film 13, and the release film 15 is removed when the protective film-forming composite sheet 1 is used. The thermosetting protective film forming film 13 becomes a protective film by thermosetting.

In the protective film-forming composite sheet 1, the pressure-sensitive adhesive layer 12 is laminated on the surface 11 a of the substrate 11, and the thermosetting protective film-forming film 13 is laminated on a part of the surface 12 a of the pressure-sensitive adhesive layer 12. Yes. And among the surface 12a of the adhesive layer 12, it is on the exposed surface in which the film 13 for thermosetting protective film formation is not laminated | stacked, and the surface 13a (upper surface and side surface) of the film 13 for thermosetting protective film formation. The release film 15 is laminated.

The protective sheet-forming composite sheet is a laser beam from the support sheet side to the thermosetting protective film-forming film or to the protective film after thermosetting the thermosetting protective film-forming film. It is preferable that the support sheet is transparent to the laser light of the laser printing so that the laser light can be transmitted through the support sheet and laser printing can be performed.

Further, in the process of manufacturing a semiconductor chip with a protective film, the semiconductor wafer is irradiated with infrared laser light from the support sheet side (SD), and the infrared laser light is transmitted through the support sheet and the inside of the semiconductor wafer. It is preferable that the support sheet has transparency to laser light in the infrared region so that the modified layer can be formed.

Furthermore, the composite sheet for forming a protective film with the semiconductor wafer is subjected to cool expansion (CE), whereby the semiconductor wafer is divided into individual pieces starting from the formation site of the modified layer of the semiconductor wafer. At this time, whether or not the thermosetting protective film forming film or the protective film has been cleaved reliably, the semiconductor chip is not chipped, or the laser light during the infrared inspection passes through the support sheet and the state of the semiconductor chip The support sheet is transparent to the laser beam used for infrared inspection, and the thermosetting protective film forming film is colored so that the manufacturing efficiency of the semiconductor device can be suppressed. It is preferable that Thereby, it can be easily inspected whether or not the thermosetting protective film forming film or the protective film has been reliably cleaved, and a decrease in the manufacturing efficiency of the semiconductor device can be suppressed.

FIG. 2 is a cross-sectional view schematically showing another embodiment of the composite sheet for forming a protective film according to the present invention. 2, the same elements as those shown in FIG. 1 are denoted by the same reference numerals as those in FIG. 1, and detailed description thereof is omitted. This also applies to the drawings after FIG.
In the protective sheet-forming composite sheet 2 shown here, a thermosetting protective film-forming film 23 is laminated on the entire surface 12 a of the pressure-sensitive adhesive layer 12, and part of the surface 23 a of the thermosetting protective film-forming film 23. The adhesive layer 16 for jigs is laminated | stacked on the exposed surface in which the adhesive layer 16 for jigs is not laminated | stacked among the surfaces 23a of the film 23 for thermosetting protective film formation, and the adhesive layer 16 for jigs. Except for the point that the release film 15 is laminated on the surface 16a (upper surface and side surface), the same as the composite sheet 1 for forming a protective film shown in FIG.

The composite sheet 2 for forming a protective film shown in FIG. 2 has the back surface of a semiconductor wafer (not shown) attached to the surface 23a of the film 23 for forming a thermosetting protective film with the release film 15 removed, The upper surface of the surface 16a of the jig adhesive layer 16 is used by being attached to a jig such as a ring frame.

The composite sheet for forming a protective film according to the present invention is not limited to the one shown in FIGS. 1 and 2, and a part of the structure shown in FIGS. 1 and 2 is changed or deleted within a range not impairing the effects of the present invention. In addition, other configurations may be added to those described above.

The thermosetting protective film-forming film is cured by heating to become a protective film. This protective film is for protecting the back surface (surface opposite to the electrode forming surface) of the semiconductor wafer or semiconductor chip. The protective film-forming film is soft and can be easily attached to an object to be attached. For example, the tensile elastic modulus (also referred to as Young's modulus) of the protective film-forming film is about 1 × 10 ⁶ to 1 × 10 ⁸ Pa at 23 ± 2 ° C.
In contrast, the tensile elastic modulus (also referred to as Young's modulus) of the protective film obtained by heat curing is hardened to about 1 × 10 ⁸ to 5.4 × 10 ⁹ Pa at 23 ± 2 ° C.
The tensile elastic modulus (also referred to as Young's modulus) of the protective film-forming film or protective film can be measured according to JIS K7161: 1994.

The composite sheet for forming a protective film of the present invention is a laminate provided with a support sheet, a thermosetting protective film forming film, and a semiconductor wafer in this order in a manufacturing method of a semiconductor chip with a protective film to be described later. Used when preparing the body.
Hereinafter, each structure of the composite film for protective film formation concerning this invention is demonstrated in detail.

〇 Base material The base material is in the form of a sheet or film, and its constituent material is cold resistance having a loss tangent (tan δ) at −15 ° C. of 0.05 or more when dynamic viscoelasticity is measured. It is preferable to select a polymer that is excellent in heat resistance and that has a storage elastic modulus at 80 ° C. (G ′ (80)) of 35.0 MPa or more. For example, a polymer having excellent heat resistance is preferably a so-called hard polymer, a polymer having a high Tg, and a polymer having excellent cold resistance is preferably a so-called soft polymer or a polymer having a low Tg.
The loss tangent (tan δ) at −15 ° C. can be determined under the same conditions as the storage elastic modulus measurement.

The loss tangent (tan δ) at −15 ° C. when dynamic viscoelasticity is measured is 0.05 or more, and the storage elastic modulus (G ′ (80)) at 80 ° C. is 35.0 MPa or more. As a constituent material of the base material satisfying both the heat resistance and the heat resistance, various heat resistant resins are added with a soft component such as a low Tg resin to impart cold resistance, and impart cold resistance. For example, a rubber component is added and modified, and a heat-resistant resin layer and a cold-resistant resin layer are laminated to form two or three layers. The heat resistant resin preferably has a storage elastic modulus (G ′ (80)) at 80 ° C. of 35.0 MPa or more, and examples thereof include polypropylene (PP) and polybutylene terephthalate (PBT). As the resin having cold resistance, a resin having a loss tangent (tan δ) at −15 ° C. of 0.05 or more when dynamic viscoelasticity is measured is preferably low density polyethylene (LDPE) or linear low density polyethylene (LLDPE). And polyethylene (PE) such as high density polyethylene (HDPE).

In addition, examples of the base resin that can be used include polyolefins other than polyethylene such as polypropylene, polybutene, polybutadiene, polymethylpentene, and norbornene resin; ethylene-vinyl acetate copolymer, ethylene- (meth) acrylic Ethylene copolymers such as acid copolymers, ethylene- (meth) acrylic acid ester copolymers, ethylene-norbornene copolymers (copolymers obtained using ethylene as a monomer); polyvinyl chloride, chloride Vinyl chloride resins such as vinyl copolymers (resins obtained using vinyl chloride as a monomer); polystyrene; polycycloolefin; polyethylene terephthalate, polyethylene naphthalate, polyethylene isophthalate, polyethylene-2,6-naphthalenedicarboxy rate Polyesters such as wholly aromatic polyesters in which all of the structural units have aromatic cyclic groups; copolymers of two or more of the above polyesters; poly (meth) acrylates; polyurethanes; polyurethane acrylates; polyimides; polyamides; Examples include fluororesins; polyacetals; modified polyphenylene oxides; polyphenylene sulfides; polysulfones;

In the present specification, “(meth) acrylic acid” is a concept including both “acrylic acid” and “methacrylic acid”. The same applies to terms similar to (meth) acrylic acid.

The resin constituting the substrate may be only one type or two or more types. When two or more kinds of resins are included in the base material, their combination and ratio can be arbitrarily selected.

The thickness of the substrate is preferably 15 to 300 μm, more preferably 50 to 200 μm, and particularly preferably 60 to 150 μm. When the thickness of the substrate is within such a range, the flexibility of the composite sheet for forming a protective film and the adhesiveness to a semiconductor wafer or semiconductor chip are further improved.
Here, “the thickness of the substrate” means the thickness of the entire substrate. For example, the thickness of the substrate composed of a plurality of layers means the total thickness of all the layers constituting the substrate. means.

The substrate may be composed of one layer (single layer) or may be composed of two or more layers. When a base material consists of multiple layers, these multiple layers may be the same or different from each other, and the combination of these multiple layers is not particularly limited.
In the case where the substrate is composed of a plurality of layers, the total thickness of each layer may be set to the preferable thickness of the substrate.

The surface roughness Ra of the surface (surface) provided with the pressure-sensitive adhesive layer of the substrate is preferably 0.001 to 0.1 μm, more preferably 0.005 to 0.08 μm, and A thickness of 01 to 0.04 μm is particularly preferable. When the surface roughness Ra of the substrate surface is not more than the upper limit value, laser printing can be performed more clearly on the protective film.
The surface roughness Ra of the substrate surface means a so-called arithmetic average roughness obtained in accordance with JIS B0601: 2001.
The surface roughness Ra of the substrate surface can be adjusted by, for example, molding conditions of the substrate, surface treatment conditions, and the like.

As a method of dividing a semiconductor wafer into semiconductor chips, an infrared laser beam is irradiated so as to be focused on a focal point set inside the semiconductor wafer, and a modified layer is formed inside the semiconductor wafer. After the formation, there is a method in which a force is applied to the semiconductor wafer to divide the semiconductor wafer from the formation site of the modified layer and separate it into pieces.
When the surface roughness Ra of the substrate surface is, for example, 0.01 to 0.2 μm, the protective sheet-forming composite sheet provided with such a substrate has a modified layer in the semiconductor wafer described above. It is suitable for use when forming a semiconductor wafer into individual pieces.

On the other hand, the surface roughness Ra of the surface (back surface) opposite to the surface (front surface) provided with the adhesive layer of the substrate, in other words, the surface (surface) provided with the protective film forming film of the support sheet. The surface roughness Ra of the opposite surface (back surface) is preferably 0.001 to 4 μm, more preferably 0.005 to 3.7 μm, and 0.01 to 3.4 μm. More preferably, the thickness is 0.02 to 3.1 μm. When the surface roughness Ra on the back surface of the substrate is less than or equal to the upper limit value, the surface roughness Ra on the surface opposite to the side in contact with the support sheet can be more easily reduced. When a semiconductor wafer is irradiated (SD) with an infrared laser beam, the infrared laser beam can pass through the support sheet to form a modified layer in the semiconductor wafer, and a protective film. In contrast, it becomes easier to perform laser printing clearly.
The surface roughness Ra of the back surface of the base material can be adjusted by, for example, molding conditions of the base material, surface treatment conditions, and the like.

The resin that is the material of the base material may be cross-linked.
In addition, the resin that is the material of the base material may be a sheet formed by extrusion molding of a thermoplastic resin, or may be a stretched sheet, and a thin layer formed by a known means of a curable resin. It may be formed into a sheet by forming and curing.
Further, the base material may be colored or printed.

The base material is preferably one containing polypropylene because it has excellent heat resistance and appropriate flexibility, so that it has cool expandability and good pick-up properties.
The base material containing polypropylene may be, for example, a single layer or a plurality of layers made of only polypropylene, or a multiple layer base material in which a polypropylene layer and a resin layer other than polypropylene are laminated. May be.
The protective film-forming film can effectively suppress the support sheet from being bent even under conditions in which the thermosetting protective film-forming film is heat-cured because the substrate has heat resistance.

The base material is preferably one having high thickness accuracy, that is, one in which variation in thickness is suppressed regardless of the part. Among the above-mentioned constituent materials, examples of materials that can be used to construct such a substrate with high thickness accuracy include polyethylene, polyolefins other than polyethylene, polyethylene terephthalate, ethylene-vinyl acetate copolymer, and the like. Is mentioned.

The base material contains various known additives such as a filler, a colorant, an antistatic agent, an antioxidant, an organic lubricant, a catalyst, and a softener (plasticizer) in addition to the main constituent material such as the resin. May be.

The optical characteristics of the base material only need to satisfy the optical characteristics of the support sheet described above. That is, the substrate may be transparent or opaque, may be colored according to the purpose, or other layers may be deposited.

In order to improve the adhesion with other layers such as a pressure-sensitive adhesive layer provided on the substrate, the substrate is subjected to a roughening treatment such as sandblast treatment, solvent treatment, corona discharge treatment, electron beam irradiation treatment, plasma treatment. The surface may be subjected to oxidation treatment such as ozone / ultraviolet irradiation treatment, flame treatment, chromic acid treatment, and hot air treatment.
The base material may have a surface subjected to primer treatment.
In addition, the base material prevents the base material from adhering to other sheets or the base material from adhering to the adsorption table when the antistatic coating layer and the protective film-forming composite sheet are stored in an overlapping manner. It may have a layer or the like.

The base material can be manufactured by a known method. For example, a base material containing a resin can be produced by molding a resin composition containing the resin.

* Adhesive layer The said adhesive layer is a sheet form or a film form, and the storage elastic modulus (G '(70)) in 70 degreeC is 0.16 Mpa or less and the storage elasticity in 23 degreeC about the physical property of the adhesive to contain. The rate (G ′ (23)) is adjusted to 0.10 MPa or more.
Examples of the adhesive include adhesive resins such as acrylic resins, urethane resins, rubber resins, silicone resins, epoxy resins, polyvinyl ethers, polycarbonates, ester resins, and acrylic resins are preferable. .

In the present invention, the “adhesive resin” is a concept including both an adhesive resin and an adhesive resin. For example, the resin itself has an adhesive property, Also included are resins that exhibit tackiness when used in combination with other components such as additives, and resins that exhibit adhesiveness due to the presence of a trigger such as heat or water.

The pressure-sensitive adhesive layer may be composed of one layer (single layer) or may be composed of two or more layers. When the pressure-sensitive adhesive layer is composed of a plurality of layers, the plurality of layers may be the same as or different from each other, and the combination of these layers is not particularly limited.

The thickness of the pressure-sensitive adhesive layer is preferably 1 to 100 μm, more preferably 1 to 60 μm, still more preferably 1 to 30 μm, and particularly preferably 3 to 20 μm.
Here, the “thickness of the pressure-sensitive adhesive layer” means the thickness of the whole pressure-sensitive adhesive layer. For example, the thickness of the pressure-sensitive adhesive layer composed of a plurality of layers is the total of all layers constituting the pressure-sensitive adhesive layer. Means the thickness.

The optical properties of the pressure-sensitive adhesive layer only need to satisfy the optical properties of the support sheet described above. That is, the pressure-sensitive adhesive layer may be transparent, opaque, or colored depending on the purpose.

The pressure-sensitive adhesive layer may be formed using an energy ray-curable pressure-sensitive adhesive, or may be formed using a non-energy ray-curable pressure-sensitive adhesive. The pressure-sensitive adhesive layer formed using the energy ray-curable pressure-sensitive adhesive can easily adjust the physical properties before and after curing.

In the present invention, “energy beam” means an electromagnetic wave or charged particle beam having energy quanta, and examples thereof include ultraviolet rays, radiation, and electron beams.
Ultraviolet rays can be irradiated, for example, by using a high-pressure mercury lamp, a fusion lamp, a xenon lamp, a black light, an LED lamp or the like as an ultraviolet ray source. The electron beam can be emitted by an electron beam accelerator or the like.
In the present invention, “energy ray curable” means the property of being cured by irradiation with energy rays, and “non-energy ray curable” means the property of not being cured even when irradiated with energy rays. .

<< Adhesive composition >>
The pressure-sensitive adhesive layer can be formed using a pressure-sensitive adhesive composition containing a pressure-sensitive adhesive. For example, an adhesive layer can be formed in the target site | part by applying an adhesive composition to the formation object surface of an adhesive layer, and making it dry as needed. A more specific method for forming the pressure-sensitive adhesive layer will be described later in detail, along with methods for forming other layers. The ratio of the content of components that do not vaporize at room temperature in the pressure-sensitive adhesive composition is usually the same as the ratio of the content of the components of the pressure-sensitive adhesive layer. Here, “normal temperature” is as described above.

The adhesive composition may be applied by a known method, for example, an air knife coater, blade coater, bar coater, gravure coater, roll coater, roll knife coater, curtain coater, die coater, knife coater, screen coater. And a method using various coaters such as a Meyer bar coater and a kiss coater.

The drying conditions of the pressure-sensitive adhesive composition are not particularly limited, but when the pressure-sensitive adhesive composition contains a solvent described later, it is preferably heated and dried. In this case, for example, at 70 to 130 ° C. for 10 seconds to It is preferable to dry under conditions of 5 minutes.

When the pressure-sensitive adhesive layer is energy ray-curable, the pressure-sensitive adhesive composition containing the energy ray-curable pressure-sensitive adhesive, that is, the energy ray-curable pressure-sensitive adhesive composition, for example, non-energy ray-curable pressure-sensitive adhesive A pressure-sensitive adhesive composition (I-1) containing a resin (I-1a) (hereinafter sometimes abbreviated as “adhesive resin (I-1a)”) and an energy ray-curable compound; Energy-ray-curable adhesive resin (I-2a) in which an unsaturated group is introduced into the side chain of the linear-curable adhesive resin (I-1a) (hereinafter referred to as “adhesive resin (I-2a)”) A pressure-sensitive adhesive composition (I-2) containing the pressure-sensitive adhesive resin (I-2a) and an energy ray curable compound, etc. Is mentioned.

<Adhesive composition (I-1)>
As described above, the pressure-sensitive adhesive composition (I-1) contains a non-energy ray-curable pressure-sensitive adhesive resin (I-1a) and an energy ray-curable compound.

[Adhesive resin (I-1a)]
The adhesive resin (I-1a) is preferably an acrylic resin.
As said acrylic resin, the acrylic polymer which has a structural unit derived from the (meth) acrylic-acid alkylester at least is mentioned, for example.
The acrylic resin may have only one type of structural unit, or two or more types of structural units. When the structural units possessed by the acrylic resin are two or more, their combination and ratio can be arbitrarily selected.

Examples of the (meth) acrylic acid alkyl ester include those in which the alkyl group constituting the alkyl ester has 1 to 20 carbon atoms, and the alkyl group is linear or branched. Is preferred.
More specifically, as (meth) acrylic acid alkyl ester, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, (meth) acrylic acid n-butyl, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, (Meth) acrylic acid 2-ethylhexyl, (meth) acrylic acid isooctyl, (meth) acrylic acid n-octyl, (meth) acrylic acid n-nonyl, (meth) acrylic acid isononyl, (meth) acrylic acid decyl, (meta) ) Undecyl acrylate, dodecyl (meth) acrylate (also called lauryl (meth) acrylate) ), Tridecyl (meth) acrylate, tetradecyl (meth) acrylate (also referred to as myristyl (meth) acrylate), pentadecyl (meth) acrylate, hexadecyl (meth) acrylate (also referred to as palmityl (meth) acrylate), Examples include heptadecyl (meth) acrylate, octadecyl (meth) acrylate (also referred to as stearyl (meth) acrylate), nonadecyl (meth) acrylate, icosyl (meth) acrylate, and the like.

From the viewpoint of improving the adhesive strength of the pressure-sensitive adhesive layer, the acrylic polymer preferably has a structural unit derived from a (meth) acrylic acid alkyl ester in which the alkyl group has 4 or more carbon atoms. In view of further improving the adhesive strength of the pressure-sensitive adhesive layer, the alkyl group preferably has 4 to 12 carbon atoms, more preferably 4 to 8 carbon atoms. In addition, the (meth) acrylic acid alkyl ester having 4 or more carbon atoms in the alkyl group is preferably an acrylic acid alkyl ester.

The acrylic polymer preferably has a structural unit derived from a functional group-containing monomer in addition to the structural unit derived from an alkyl (meth) acrylate.
As the functional group-containing monomer, for example, when the functional group reacts with a crosslinking agent described later, it becomes a starting point of crosslinking, and the functional group reacts with an unsaturated group in the unsaturated group-containing compound described later. The thing which enables introduction | transduction of an unsaturated group to the side chain of an acrylic polymer is mentioned.

Examples of the functional group in the functional group-containing monomer include a hydroxyl group, a carboxy group, an amino group, and an epoxy group.
That is, examples of the functional group-containing monomer include a hydroxyl group-containing monomer, a carboxy group-containing monomer, an amino group-containing monomer, and an epoxy group-containing monomer.

Examples of the hydroxyl group-containing monomer include hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, (meth) Hydroxyalkyl (meth) acrylates such as 2-hydroxybutyl acrylate, 3-hydroxybutyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate; non- (meth) acrylic non-methacrylates such as vinyl alcohol and allyl alcohol Saturated alcohols (also referred to as unsaturated alcohols having no (meth) acryloyl skeleton), and the like can be given.

Examples of the carboxy group-containing monomer include ethylenically unsaturated monocarboxylic acids such as (meth) acrylic acid and crotonic acid (also referred to as monocarboxylic acids having an ethylenically unsaturated bond); fumaric acid, itaconic acid, maleic acid Ethylenically unsaturated dicarboxylic acids such as citraconic acid (also referred to as dicarboxylic acids having an ethylenically unsaturated bond); anhydrides of the ethylenically unsaturated dicarboxylic acids; carboxyalkyl (meth) acrylates such as 2-carboxyethyl methacrylate Examples include esters.

The functional group-containing monomer is preferably a hydroxyl group-containing monomer or a carboxy group-containing monomer, more preferably a hydroxyl group-containing monomer.

The functional group-containing monomer constituting the acrylic polymer may be only one type or two or more types. When there are two or more functional group-containing monomers, their combination and ratio can be arbitrarily selected.

In the acrylic polymer, the content of the structural unit derived from the functional group-containing monomer is preferably 1 to 35% by mass, more preferably 2 to 32% by mass with respect to the total mass of the structural unit. The content is preferably 3 to 30% by mass.

In addition to the structural unit derived from the (meth) acrylic acid alkyl ester and the structural unit derived from the functional group-containing monomer, the acrylic polymer may further have a structural unit derived from another monomer.
The other monomer is not particularly limited as long as it is copolymerizable with (meth) acrylic acid alkyl ester or the like.
Examples of the other monomer include styrene, α-methylstyrene, vinyl toluene, vinyl formate, vinyl acetate, acrylonitrile, acrylamide and the like.

The other monomer constituting the acrylic polymer may be one kind or two or more kinds. When the said other monomer is 2 or more types, those combinations and ratios can be selected arbitrarily.

The acrylic polymer can be used as the above-mentioned non-energy ray curable adhesive resin (I-1a).
On the other hand, the functional group in the acrylic polymer is reacted with an unsaturated group-containing compound having an energy beam polymerizable unsaturated group (also referred to as energy beam polymerizable group). It can be used as an adhesive resin (I-2a).

The pressure-sensitive adhesive composition (I-1) contained in the pressure-sensitive adhesive composition (I-1) may be one type or two or more types. When the adhesive resin (I-1a) is two or more, the combination and ratio thereof can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-1), the content of the pressure-sensitive adhesive resin (I-1a) is preferably 5 to 99% by mass with respect to the total mass of the pressure-sensitive adhesive composition (I-1). It is more preferably 10 to 95% by mass, particularly preferably 15 to 90% by mass.

[Energy ray curable compound]
Examples of the energy ray-curable compound contained in the pressure-sensitive adhesive composition (I-1) include monomers or oligomers having an energy ray-polymerizable unsaturated group and curable by irradiation with energy rays.
Among the energy ray curable compounds, examples of the monomer include trimethylolpropane tri (meth) acrylate, pentaerythritol (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and 1,4. Polybutyl (meth) acrylates such as butylene glycol di (meth) acrylate and 1,6-hexanediol (meth) acrylate; urethane (meth) acrylate; polyester (meth) acrylate; polyether (meth) acrylate; epoxy ( And (meth) acrylate.
Among the energy ray-curable compounds, examples of the oligomer include an oligomer formed by polymerizing the monomers exemplified above.
The energy ray-curable compound is preferably a urethane (meth) acrylate or a urethane (meth) acrylate oligomer from the viewpoint that the molecular weight is relatively large and the storage elastic modulus of the pressure-sensitive adhesive layer is hardly lowered.

The energy ray-curable compound contained in the pressure-sensitive adhesive composition (I-1) may be only one type or two or more types. When the energy ray curable compounds are two or more, the combination and ratio thereof can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-1), the content of the energy ray-curable compound is preferably 1 to 95% by mass with respect to the total mass of the pressure-sensitive adhesive composition (I-1). It is more preferably 5 to 90% by mass, and particularly preferably 10 to 85% by mass.

[Crosslinking agent]
When the acrylic polymer having a structural unit derived from a functional group-containing monomer in addition to the structural unit derived from (meth) acrylic acid alkyl ester is used as the adhesive resin (I-1a), a pressure-sensitive adhesive composition ( I-1) preferably further contains a crosslinking agent.

For example, the cross-linking agent reacts with the functional group to cross-link the adhesive resins (I-1a).
Examples of the cross-linking agent include tolylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, isocyanate-based cross-linking agents such as adducts of these diisocyanates (also referred to as cross-linking agents having an isocyanate group), and epoxy-based cross-linking such as ethylene glycol glycidyl ether. Agent (also referred to as a crosslinking agent having a glycidyl group); Aziridine-based crosslinking agent (also referred to as a crosslinking agent having an aziridinyl group) such as hexa [1- (2-methyl) -aziridinyl] triphosphatriazine; Metal such as aluminum chelate Examples thereof include chelate-based cross-linking agents (also referred to as cross-linking agents having a metal chelate structure); isocyanurate-based cross-linking agents (also referred to as cross-linking agents having an isocyanuric acid skeleton).
The crosslinking agent is preferably an isocyanate-based crosslinking agent from the viewpoints of improving the cohesive strength of the pressure-sensitive adhesive and improving the pressure-sensitive adhesive strength of the pressure-sensitive adhesive layer, and being easily available.

The crosslinking agent contained in the pressure-sensitive adhesive composition (I-1) may be only one kind or two or more kinds. When two or more crosslinking agents are used, the combination and ratio thereof can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-1), the content of the crosslinking agent is preferably 0.01 to 50 parts by weight with respect to 100 parts by weight of the pressure-sensitive adhesive resin (I-1a). The amount is more preferably 0.1 to 20 parts by mass, and particularly preferably 0.3 to 15 parts by mass.

[Photopolymerization initiator]
The pressure-sensitive adhesive composition (I-1) may further contain a photopolymerization initiator. The pressure-sensitive adhesive composition (I-1) containing a photopolymerization initiator sufficiently proceeds with a curing reaction even when irradiated with a relatively low energy beam such as ultraviolet rays.

Examples of the photopolymerization initiator include benzoin compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, methyl benzoin benzoate, and benzoin dimethyl ketal; acetophenone, 2-hydroxy Acetophenone compounds such as -2-methyl-1-phenyl-propan-1-one and 2,2-dimethoxy-1,2-diphenylethane-1-one; bis (2,4,6-trimethylbenzoyl) phenylphosphine Acylphosphine oxide compounds such as oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide; Sulfidation of benzylphenyl sulfide, tetramethylthiuram monosulfide, etc. An α-ketol compound such as 1-hydroxycyclohexyl phenyl ketone; an azo compound such as azobisisobutyronitrile; a titanocene compound such as titanocene; a thioxanthone compound such as thioxanthone; a peroxide compound; a diketone compound such as diacetyl; Benzophenone; 2,4-diethylthioxanthone; 1,2-diphenylmethane; 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanone; 2-chloroanthraquinone and the like.
As the photopolymerization initiator, for example, a quinone compound such as 1-chloroanthraquinone; a photosensitizer such as amine can be used.

The photopolymerization initiator contained in the pressure-sensitive adhesive composition (I-1) may be one kind or two or more kinds. When the said photoinitiator is 2 or more types, those combinations and ratios can be selected arbitrarily.

In the pressure-sensitive adhesive composition (I-1), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of the energy ray curable compound. The amount is more preferably 0.03 to 10 parts by weight, and particularly preferably 0.05 to 5 parts by weight.

[Other additives]
The pressure-sensitive adhesive composition (I-1) may contain other additives that do not fall under any of the above-mentioned components within a range not impairing the effects of the present invention.
Examples of the other additives include antistatic agents, antioxidants, softeners (also referred to as plasticizers), fillers (also referred to as fillers), rust inhibitors, colorants (pigments, dyes, etc.), and sensitization. Known additives such as an agent, a tackifier, a reaction retarder, and a crosslinking accelerator (also referred to as a catalyst) can be used.
Incidentally, the reaction retarding agent means, for example, an undesired crosslinking reaction in the pressure-sensitive adhesive composition (I-1) during storage by the action of the catalyst mixed in the pressure-sensitive adhesive composition (I-1). It suppresses progress. Examples of the reaction retarder include those that form a chelate complex by chelation against a catalyst, and more specifically, those having two or more carbonyl groups (—C (═O) —) in one molecule. Can be mentioned.

The above-mentioned other additives contained in the pressure-sensitive adhesive composition (I-1) may be only one kind or two or more kinds. When the said other additive is 2 or more types, those combinations and ratios can be selected arbitrarily.

In the pressure-sensitive adhesive composition (I-1), the content of other additives is not particularly limited, and may be appropriately selected according to the type.

[solvent]
The pressure-sensitive adhesive composition (I-1) may contain a solvent. Since the pressure-sensitive adhesive composition (I-1) contains a solvent, the suitability for coating on the surface to be coated is improved.

The solvent is preferably an organic solvent. Examples of the organic solvent include ketones such as methyl ethyl ketone and acetone; esters such as ethyl acetate (also referred to as carboxylic acid esters); ethers such as tetrahydrofuran and dioxane; cyclohexane, n- Examples thereof include aliphatic hydrocarbons such as hexane; aromatic hydrocarbons such as toluene and xylene; alcohols such as 1-propanol and 2-propanol.

As the solvent, for example, the solvent used in the production of the adhesive resin (I-1a) may be used as it is in the adhesive composition (I-1) without being removed from the adhesive resin (I-1a). In addition, the same or different type of solvent used in the production of the adhesive resin (I-1a) may be added separately during the production of the adhesive composition (I-1).

The solvent contained in the pressure-sensitive adhesive composition (I-1) may be one kind or two or more kinds. When two or more solvents are used, their combination and ratio can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-1), the content of the solvent is not particularly limited, and may be adjusted as appropriate.

<Adhesive composition (I-2)>
As described above, the pressure-sensitive adhesive composition (I-2) is an energy-ray-curable pressure-sensitive adhesive resin in which an unsaturated group is introduced into the side chain of the non-energy-ray-curable pressure-sensitive adhesive resin (I-1a). (I-2a) is contained.

[Adhesive resin (I-2a)]
The adhesive resin (I-2a) can be obtained, for example, by reacting a functional group in the adhesive resin (I-1a) with an unsaturated group-containing compound having an energy ray polymerizable unsaturated group.

The unsaturated group-containing compound can be bonded to the adhesive resin (I-1a) by reacting with the functional group in the adhesive resin (I-1a) in addition to the energy ray polymerizable unsaturated group. A compound having a group.
Examples of the energy beam polymerizable unsaturated group include (meth) acryloyl group, vinyl group (also referred to as ethenyl group), allyl group (also referred to as 2-propenyl group), and (meth) acryloyl group is preferable. .
Examples of the group capable of binding to the functional group in the adhesive resin (I-1a) include, for example, an isocyanate group and a glycidyl group that can be bonded to a hydroxyl group or an amino group, and a hydroxyl group and an amino group that can be bonded to a carboxy group or an epoxy group. Etc.

Examples of the unsaturated group-containing compound include (meth) acryloyloxyethyl isocyanate, (meth) acryloyl isocyanate, glycidyl (meth) acrylate, and the like.

The pressure-sensitive adhesive composition (I-2) contained in the pressure-sensitive adhesive composition (I-2) may be one type or two or more types. When the adhesive resin (I-2a) is two or more, the combination and ratio thereof can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-2), the content of the pressure-sensitive adhesive resin (I-2a) is preferably 5 to 99% by mass with respect to the total mass of the pressure-sensitive adhesive composition (I-2). The content is more preferably 10 to 95% by mass, and particularly preferably 10 to 90% by mass.

[Crosslinking agent]
When the acrylic polymer having a structural unit derived from a functional group-containing monomer similar to that in the adhesive resin (I-1a) is used as the adhesive resin (I-2a), for example, an adhesive composition ( I-2) may further contain a crosslinking agent.

Examples of the crosslinking agent in the pressure-sensitive adhesive composition (I-2) include the same crosslinking agents as in the pressure-sensitive adhesive composition (I-1).
The crosslinking agent contained in the pressure-sensitive adhesive composition (I-2) may be only one kind or two or more kinds. When two or more crosslinking agents are used, the combination and ratio thereof can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-2), the content of the crosslinking agent is preferably 0.01 to 50 parts by weight with respect to 100 parts by weight of the pressure-sensitive adhesive resin (I-2a). The amount is more preferably 0.1 to 20 parts by weight, and particularly preferably 0.3 to 15 parts by weight.

[Photopolymerization initiator]
The pressure-sensitive adhesive composition (I-2) may further contain a photopolymerization initiator. The pressure-sensitive adhesive composition (I-2) containing the photopolymerization initiator sufficiently proceeds with the curing reaction even when irradiated with a relatively low energy beam such as ultraviolet rays.

Examples of the photopolymerization initiator in the pressure-sensitive adhesive composition (I-2) include the same photopolymerization initiator as in the pressure-sensitive adhesive composition (I-1).
The photopolymerization initiator contained in the pressure-sensitive adhesive composition (I-2) may be one kind or two or more kinds. When there are two or more photopolymerization initiators, their combination and ratio can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-2), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by weight with respect to 100 parts by weight of the pressure-sensitive adhesive resin (I-2a). 0.03 to 10 parts by mass is more preferable, and 0.05 to 5 parts by mass is particularly preferable.

[Other additives]
The pressure-sensitive adhesive composition (I-2) may contain other additives that do not fall under any of the above-mentioned components within a range not impairing the effects of the present invention.
Examples of the other additive in the pressure-sensitive adhesive composition (I-2) include the same additives as those in the pressure-sensitive adhesive composition (I-1).
The other additive contained in the pressure-sensitive adhesive composition (I-2) may be one kind or two or more kinds. When there are two or more other additives, their combination and ratio can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-2), the content of other additives is not particularly limited, and may be appropriately selected according to the type.

[solvent]
The pressure-sensitive adhesive composition (I-2) may contain a solvent for the same purpose as that of the pressure-sensitive adhesive composition (I-1).
Examples of the solvent in the pressure-sensitive adhesive composition (I-2) include the same solvents as those in the pressure-sensitive adhesive composition (I-1).
The solvent contained in the pressure-sensitive adhesive composition (I-2) may be only one kind or two or more kinds. When two or more solvents are used, their combination and ratio can be arbitrarily selected.
In the pressure-sensitive adhesive composition (I-2), the content of the solvent is not particularly limited, and may be adjusted as appropriate.

<Adhesive composition (I-3)>
As described above, the pressure-sensitive adhesive composition (I-3) contains the pressure-sensitive adhesive resin (I-2a) and an energy ray-curable compound.

In the pressure-sensitive adhesive composition (I-3), the content of the pressure-sensitive adhesive resin (I-2a) is preferably 5 to 99% by mass with respect to the total mass of the pressure-sensitive adhesive composition (I-3). It is more preferably 10 to 95% by mass, particularly preferably 15 to 90% by mass.

[Energy ray curable compound]
Examples of the energy ray-curable compound contained in the pressure-sensitive adhesive composition (I-3) include monomers and oligomers having an energy ray-polymerizable unsaturated group and curable by irradiation with energy rays. Examples thereof include the same energy ray curable compounds contained in the product (I-1).
The energy ray-curable compound contained in the pressure-sensitive adhesive composition (I-3) may be only one type or two or more types. When the energy ray curable compounds are two or more, the combination and ratio thereof can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-3), the content of the energy ray-curable compound is 0.01 to 300 parts by mass with respect to 100 parts by mass of the adhesive resin (I-2a). It is preferably 0.03 to 200 parts by mass, more preferably 0.05 to 100 parts by mass.

[Photopolymerization initiator]
The pressure-sensitive adhesive composition (I-3) may further contain a photopolymerization initiator. The pressure-sensitive adhesive composition (I-3) containing a photopolymerization initiator sufficiently undergoes a curing reaction even when irradiated with energy rays of relatively low energy such as ultraviolet rays.

Examples of the photopolymerization initiator in the pressure-sensitive adhesive composition (I-3) include the same photopolymerization initiator as in the pressure-sensitive adhesive composition (I-1).
The photopolymerization initiator contained in the pressure-sensitive adhesive composition (I-3) may be only one kind or two or more kinds. When there are two or more photopolymerization initiators, their combination and ratio can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-3), the content of the photopolymerization initiator is 0.01 to about 100 parts by mass of the total content of the pressure-sensitive adhesive resin (I-2a) and the energy ray curable compound. The amount is preferably 20 parts by mass, more preferably 0.03 to 10 parts by mass, and particularly preferably 0.05 to 5 parts by mass.

[Other additives]
The pressure-sensitive adhesive composition (I-3) may contain other additives that do not fall under any of the above-mentioned components within a range not impairing the effects of the present invention.
Examples of the other additive include the same additives as those in the pressure-sensitive adhesive composition (I-1).
The other additive contained in the pressure-sensitive adhesive composition (I-3) may be one kind or two or more kinds. When there are two or more other additives, their combination and ratio can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-3), the content of other additives is not particularly limited, and may be appropriately selected according to the type.

[solvent]
The pressure-sensitive adhesive composition (I-3) may contain a solvent for the same purpose as that of the pressure-sensitive adhesive composition (I-1).
Examples of the solvent in the pressure-sensitive adhesive composition (I-3) include the same solvents as those in the pressure-sensitive adhesive composition (I-1).
The solvent contained in the pressure-sensitive adhesive composition (I-3) may be only one type or two or more types. When two or more solvents are used, their combination and ratio can be arbitrarily selected.
In the pressure-sensitive adhesive composition (I-3), the content of the solvent is not particularly limited, and may be adjusted as appropriate.

<Adhesive compositions other than adhesive compositions (I-1) to (I-3)>
So far, the pressure-sensitive adhesive composition (I-1), the pressure-sensitive adhesive composition (I-2) and the pressure-sensitive adhesive composition (I-3) have been mainly described. General pressure-sensitive adhesive compositions other than these three types of pressure-sensitive adhesive compositions (referred to herein as “pressure-sensitive adhesive compositions other than pressure-sensitive adhesive compositions (I-1) to (I-3)”) But it can be used similarly.

Examples of the pressure-sensitive adhesive composition other than the pressure-sensitive adhesive compositions (I-1) to (I-3) include non-energy ray-curable pressure-sensitive adhesive compositions in addition to the energy ray-curable pressure-sensitive adhesive composition.
Non-energy ray curable pressure-sensitive adhesive compositions include, for example, acrylic resin, urethane resin, rubber resin, silicone resin, epoxy resin, polyvinyl ether, polycarbonate, ester resin, etc. An adhesive composition (I-4) containing an adhesive resin (I-1a) is preferable, and an adhesive composition containing an acrylic resin is preferred.

The pressure-sensitive adhesive composition other than the pressure-sensitive adhesive compositions (I-1) to (I-3) preferably contains one or more kinds of crosslinking agents, and the content thereof is the above-mentioned pressure-sensitive adhesive composition. It can be the same as in the case of (I-1).

<Adhesive composition (I-4)>
Preferred examples of the pressure-sensitive adhesive composition (I-4) include those containing the pressure-sensitive adhesive resin (I-1a) and a crosslinking agent.

[Adhesive resin (I-1a)]
Examples of the adhesive resin (I-1a) in the pressure-sensitive adhesive composition (I-4) include the same as the pressure-sensitive adhesive resin (I-1a) in the pressure-sensitive adhesive composition (I-1).
The adhesive resin (I-1a) contained in the adhesive composition (I-4) may be one type or two or more types. When the adhesive resin (I-1a) is two or more, the combination and ratio thereof can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-4), the content of the pressure-sensitive adhesive resin (I-1a) is preferably 5 to 99% by mass with respect to the total mass of the pressure-sensitive adhesive composition (I-4). It is more preferably 10 to 95% by mass, particularly preferably 15 to 90% by mass.

[Crosslinking agent]
When the acrylic polymer having a structural unit derived from a functional group-containing monomer in addition to the structural unit derived from (meth) acrylic acid alkyl ester is used as the adhesive resin (I-1a), a pressure-sensitive adhesive composition ( I-4) preferably further contains a crosslinking agent.

Examples of the crosslinking agent in the pressure-sensitive adhesive composition (I-4) include the same crosslinking agents as those in the pressure-sensitive adhesive composition (I-1).
The crosslinking agent contained in the pressure-sensitive adhesive composition (I-4) may be only one kind or two or more kinds. When two or more crosslinking agents are used, the combination and ratio thereof can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-4), the content of the crosslinking agent is preferably 0.01 to 50 parts by weight with respect to 100 parts by weight of the pressure-sensitive adhesive resin (I-1a). The amount is more preferably 0.1 to 20 parts by mass, and particularly preferably 0.3 to 15 parts by mass.

[Other additives]
The pressure-sensitive adhesive composition (I-4) may contain other additives that do not fall under any of the above-mentioned components within a range not impairing the effects of the present invention.
Examples of the other additive include the same additives as those in the pressure-sensitive adhesive composition (I-1).
The other additive contained in the pressure-sensitive adhesive composition (I-4) may be one kind or two or more kinds. When there are two or more other additives, their combination and ratio can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-4), the content of other additives is not particularly limited, and may be appropriately selected according to the type.

[solvent]
The pressure-sensitive adhesive composition (I-4) may contain a solvent for the same purpose as that of the pressure-sensitive adhesive composition (I-1).
Examples of the solvent in the pressure-sensitive adhesive composition (I-4) include the same solvents as those in the pressure-sensitive adhesive composition (I-1).
The solvent contained in the pressure-sensitive adhesive composition (I-4) may be one type or two or more types. When two or more solvents are used, their combination and ratio can be arbitrarily selected.
In the pressure-sensitive adhesive composition (I-4), the content of the solvent is not particularly limited and may be appropriately adjusted.

<< Method for producing pressure-sensitive adhesive composition >>
The pressure-sensitive adhesive compositions other than the pressure-sensitive adhesive compositions (I-1) to (I-3) such as the pressure-sensitive adhesive compositions (I-1) to (I-3) and the pressure-sensitive adhesive composition (I-4) It is obtained by blending each component for constituting the pressure-sensitive adhesive composition, such as the pressure-sensitive adhesive and components other than the pressure-sensitive adhesive, if necessary.
The order of addition at the time of blending each component is not particularly limited, and two or more components may be added simultaneously.
When a solvent is used, it may be used by mixing the solvent with any compounding component other than the solvent and diluting the compounding component in advance, or by diluting any compounding component other than the solvent in advance. You may use it by mixing a solvent with these compounding ingredients, without leaving.
The method of mixing each component at the time of compounding is not particularly limited, from a known method such as a method of mixing by rotating a stirrer or a stirring blade; a method of mixing using a mixer; a method of mixing by applying ultrasonic waves What is necessary is just to select suitably.
The temperature and time during the addition and mixing of each component are not particularly limited as long as each compounding component does not deteriorate, and may be adjusted as appropriate, but the temperature is preferably 15 to 30 ° C.

○ Support sheet The support sheet is formed by laminating the base material and the pressure-sensitive adhesive layer, and corresponds to a sheet serving as a dicing sheet for protecting the surface of the protective film-forming film in a dicing process or the like. To do.

The thickness of the support sheet may be appropriately selected depending on the purpose, but can provide sufficient flexibility to the protective film-forming composite sheet. In view of handling at the time of manufacture, the thickness is preferably 10 to 500 μm, more preferably 20 to 350 μm, and particularly preferably 30 to 200 μm.
Here, the “thickness of the support sheet” means the total value of the thickness of the base material and the thickness of the pressure-sensitive adhesive layer.
Note that, at least one surface of the support sheet can be an uneven surface, but the thickness of the support sheet is calculated with the tip of the convex portion as one starting point at a portion including the convex portion on the uneven surface of the support sheet. That's fine.
In the present specification, “thickness” can be obtained by measuring the thickness using, for example, a constant pressure thickness measuring instrument at five randomly selected locations and calculating the average of the measured values.

The support sheet is preferably transparent for the above reasons. However, it may be opaque and may be colored according to the purpose as long as the transparency of a predetermined laser wavelength and the inspectability for cleaving can be ensured.

Specifically, in the support sheet, the transmittance of light having a wavelength of 532 nm is preferably 30% or more, more preferably 50% or more, and particularly preferably 70% or more. When the light transmittance is within such a range, when the protective film-forming film or the protective film is irradiated with laser light through the support sheet and printed on these, printing can be performed more clearly.
On the other hand, in the support sheet, the upper limit value of the transmittance of light having a wavelength of 532 nm is not particularly limited, but can be, for example, 95%.
That is, in the support sheet, the transmittance of light having a wavelength of 532 nm is preferably 30% to 95%, more preferably 50% to 95%, and particularly preferably 70% to 95%.

Further, in the support sheet, the transmittance of light having a wavelength of 1064 nm is preferably 30% or more, more preferably 50% or more, and particularly preferably 70% or more. Similarly, in the support sheet, the transmittance of light having a wavelength of 1342 nm is preferably 30% or more, more preferably 50% or more, and particularly preferably 70% or more. When the light transmittance is in such a range, when the semiconductor wafer is irradiated with infrared laser light (SD) from the support sheet side, the infrared laser light is transmitted through the support sheet. A modified layer can be satisfactorily formed inside a semiconductor wafer, and when a protective film-forming film or protective film is irradiated with a laser beam through a support sheet and printed on these, it becomes clearer. Can be printed.
On the other hand, in the support sheet, the upper limit value of the transmittance of light having a wavelength of 1064 nm is not particularly limited, but can be, for example, 95%. Similarly, in the support sheet, the upper limit value of the transmittance of light having a wavelength of 1342 nm is not particularly limited, but can be, for example, 95%.
That is, in the support sheet, the transmittance of light having a wavelength of 1064 nm is preferably 30% to 95%, more preferably 50% to 95%, and particularly preferably 70% to 95%. Similarly, in the support sheet, the transmittance of light having a wavelength of 1342 nm is preferably 30% to 95%, more preferably 50% to 95%, and particularly preferably 70% to 95%.

A film for forming a thermosetting protective film The film for forming a thermosetting protective film is thermosetting, and finally becomes a protective film having high impact resistance after being subjected to thermosetting. This protective film prevents the occurrence of cracks in the semiconductor chip after the dicing process, for example.
The protective film-forming film can be formed using a thermosetting protective film-forming composition described later.

The thermosetting protective film-forming film may be a single layer (single layer) or a multilayer of two or more layers. When the film for forming a thermosetting protective film is a plurality of layers, these layers may be the same or different from each other, and the combination of these layers is not particularly limited.

The thickness of the thermosetting protective film-forming film is not particularly limited, but is preferably 1 to 100 μm, more preferably 5 to 75 μm, and particularly preferably 5 to 50 μm. When the thickness of the thermosetting protective film-forming film is equal to or greater than the lower limit, the adhesive force to the adherend semiconductor wafer and semiconductor chip is further increased. Moreover, when the thickness of the thermosetting protective film-forming film is not more than the above upper limit value, the protective film that is a cured product can be more easily cleaved using a shearing force at the time of cool expansion.

Preferred examples of the film for forming a thermosetting protective film include those containing a polymer component (A) and a thermosetting component (B). The polymer component (A) is a component that can be regarded as formed by polymerization reaction of the polymerizable compound. The thermosetting component (B) is a component that can undergo a curing (polymerization) reaction using heat as a reaction trigger. In the present invention, the polymerization reaction includes a polycondensation reaction. Hereinafter, the “thermosetting protective film-forming film” is also simply referred to as “protective film-forming film”.

In the present invention, the adhesive force between the protective film obtained by curing the protective film-forming film and the pressure-sensitive adhesive layer is preferably 50 to 1500 mN / 25 mm, and preferably 52 to 1450 mN / 25 mm. Is more preferable, and 53 to 1430 mN / 25 mm is particularly preferable. When the adhesive force is equal to or higher than the lower limit value, pickup of a semiconductor chip with a protective film other than the target is suppressed during pickup of the semiconductor chip with a protective film, and the target semiconductor chip with a protective film is highly selectively picked up. it can. Moreover, when the adhesive force is equal to or less than the upper limit value, cracking and chipping of the semiconductor chip are suppressed when the semiconductor chip with a protective film is picked up. Thus, when the adhesive force is within a specific range, the composite sheet for forming a protective film has good pickup suitability.

The adhesive force between the protective film and the adhesive layer can be measured by the following method.
That is, a protective film-forming composite sheet having a width of 25 mm and an arbitrary length is attached to an adherend by the protective film-forming film.
Next, the protective film-forming film is thermally cured to form a protective film, and then the support sheet is peeled off from the protective film attached to the adherend at a peeling speed of 300 mm / min. The peeling at this time is such that the supporting sheet is in the length direction (the length direction of the composite sheet for forming the protective film) so that the surfaces of the protective film and the pressure-sensitive adhesive layer that are in contact with each other form an angle of 180 °. The so-called 180 ° peeling is performed. And the load (peeling force) at the time of this 180 degree | times peeling is measured, and let the measured value be the said adhesive force (mN / 25mm).

The length of the composite sheet for forming a protective film used for the measurement is not particularly limited as long as the adhesive force can be stably detected, but is preferably 100 to 300 mm. In the measurement, it is preferable that the protective sheet-forming composite sheet is stuck on the adherend and the sticking state of the protective film-forming composite sheet is stabilized.

In the present invention, the adhesive force between the protective film-forming film and the pressure-sensitive adhesive layer is not particularly limited, and may be, for example, 80 mN / 25 mm or more, preferably 100 mN / 25 mm or more, It is more preferably 150 mN / 25 mm or more, and particularly preferably 200 mN / 25 mm or more. When the adhesive force is 100 mN / 25 mm or more, peeling between the protective film-forming film and the support sheet is suppressed during dicing. For example, a semiconductor chip having a protective film-forming film on the back surface is removed from the support sheet. Scattering is suppressed.

On the other hand, the upper limit value of the adhesive force between the protective film-forming film and the pressure-sensitive adhesive layer is not particularly limited, and can be any of, for example, 4000 mN / 25 mm, 3000 mN / 25 mm, 2000 mN / 25 mm, and the like.
That is, the adhesive force between the protective film-forming film and the pressure-sensitive adhesive layer is preferably 80 to 4000 mN / 25 mm, more preferably 100 to 4000 mN / 25 mm, further preferably 150 to 3000 mN / 25 mm, and 200 to 2000 mN / 25 mm. Is particularly preferred.
However, these are examples.

The adhesive force between the protective film-forming film and the pressure-sensitive adhesive layer is the same as the adhesive force between the protective film and the support sheet, except that the protective film-forming film used for measurement is not thermally cured. It can be measured in the same way.

The adhesive force between the protective film and the pressure-sensitive adhesive layer and the adhesive force between the protective film-forming film and the pressure-sensitive adhesive layer are, for example, the types and amounts of the components contained in the protective film-forming film, It can adjust suitably by adjusting the constituent material of an agent layer, the surface state of an adhesive layer, etc.

For example, the type and amount of the component contained in the protective film-forming film can be adjusted by the type and amount of the component contained in the protective film-forming composition described below. And among the components of the composition for forming a protective film, for example, the type and content of the polymer (b) having no energy ray curable group, the content of the filler (d), or the crosslinking agent (f) By adjusting the content of, the adhesive force between the protective film or the protective film-forming film and the support sheet can be adjusted more easily.

In addition, for example, when the layer for providing the protective film-forming film in the support sheet is an adhesive layer, the constituent material can be adjusted as appropriate by adjusting the type and amount of components contained in the adhesive layer. . And the kind and quantity of the component of an adhesive layer can be adjusted with the kind and quantity of the component of an above-mentioned adhesive composition.
On the other hand, when the layer for providing the protective film-forming film in the support sheet is a base material, the adhesive force between the protective film or the protective film-forming film and the support sheet is not limited to the constituent material of the base material. The surface condition of the substrate can also be adjusted. And the surface state of the base material is, for example, the surface treatment mentioned above as improving the adhesion with the other layers of the base material, that is, the concavo-convex treatment by sandblasting, solvent treatment, etc .; corona discharge treatment, It can be adjusted by performing any one of an electron beam irradiation treatment, a plasma treatment, an ozone / ultraviolet ray irradiation treatment, a flame treatment, a chromic acid treatment, a hot air treatment and the like; and a primer treatment.

The protective film-forming film is thermosetting and has energy beam curable properties, and may contain, for example, an energy beam curable component (a).
The energy ray curable component (a) is preferably uncured, preferably tacky, and more preferably uncured and tacky.

The protective film-forming film may be a single layer (single layer) or a plurality of layers of two or more layers. When the protective film-forming film has a plurality of layers, these layers may be the same as or different from each other, and the combination of these layers is not particularly limited.

The thickness of the protective film-forming film is preferably 1 to 100 μm, more preferably 5 to 75 μm, and particularly preferably 5 to 50 μm. When the thickness of the protective film-forming film is equal to or more than the lower limit value, a protective film having higher protective ability can be formed. Moreover, when the thickness of the protective film-forming film is equal to or less than the upper limit, an excessive thickness is suppressed.
Here, the “thickness of the protective film-forming film” means the thickness of the entire protective film-forming film. For example, the thickness of the protective film-forming film composed of a plurality of layers means the total thickness of all layers constituting the protective film-forming film.

The curing conditions for forming the protective film by curing the protective film-forming film are not particularly limited as long as the protective film has a degree of curing that sufficiently exhibits its function, and the type of the protective film-forming film is not limited. Accordingly, it may be appropriately selected.
For example, the heating temperature during curing of the thermosetting protective film-forming film is preferably 100 ° C. or higher and 200 ° C. or lower, more preferably 110 ° C. or higher and 180 ° C. or lower, and 120 ° C. or higher and 170 ° C. or lower. It is particularly preferred. The heating time during the curing is preferably 0.5 hours or more and 5 hours or less, more preferably 0.5 hours or more and 3 hours or less, and particularly preferably 1 hour or more and 2 hours or less. preferable.

<< The composition for thermosetting protective film formation >>
The film for forming a thermosetting protective film can be formed using a composition for forming a thermosetting protective film containing the constituent materials. For example, the composition for forming a thermosetting protective film is applied to the surface to be formed of the film for forming a thermosetting protective film, and dried as necessary to form a thermosetting protective film on the target site. A film can be formed. The ratio of the content of components that do not vaporize at room temperature in the thermosetting protective film-forming composition is usually the same as the content ratio of the components of the thermosetting protective film-forming film. Here, “normal temperature” is as described above.

Application of the thermosetting protective film-forming composition can be performed, for example, in the same manner as in the case of application of the above-described pressure-sensitive adhesive composition.

The drying conditions of the composition for forming a thermosetting protective film are not particularly limited, but when the composition for forming a thermosetting protective film contains a solvent to be described later, it is preferably dried by heating. For example, drying is preferably performed at 70 to 130 ° C. for 10 seconds to 5 minutes.

<Composition for forming protective film (III-1)>
As the composition for forming a thermosetting protective film, for example, a composition (III-1) for forming a thermosetting protective film containing a polymer component (A) and a thermosetting component (B) (in this specification) May be abbreviated as “composition for forming protective film (III-1)”).

[Polymer component (A)]
The polymer component (A) is a polymer compound for imparting film-forming properties, flexibility and the like to the thermosetting protective film-forming film.
The polymer component (A) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one kind or two or more kinds. When there are two or more polymer components (A), their combination and ratio can be arbitrarily selected.

Examples of the polymer component (A) include an acrylic resin (a resin having a (meth) acryloyl group), a polyester, a urethane resin (a resin having a urethane bond), an acrylic urethane resin, and a silicone resin (having a siloxane bond). Resin), rubber resin (resin having a rubber structure), phenoxy resin, thermosetting polyimide and the like, and acrylic resin is preferable.

As said acrylic resin in a polymer component (A), a well-known acrylic polymer is mentioned.
The weight average molecular weight (Mw) of the acrylic resin is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1500,000. When the weight average molecular weight of the acrylic resin is equal to or more than the lower limit, the shape stability (time stability during storage) of the thermosetting protective film-forming film is improved. In addition, when the weight average molecular weight of the acrylic resin is not more than the above upper limit value, the thermosetting protective film forming film easily follows the uneven surface of the adherend, and the adherend and the thermosetting protective film are formed. Occurrence of voids and the like with the film is further suppressed.
In the present specification, “weight average molecular weight” means a polystyrene equivalent value measured by a gel permeation chromatography (GPC) method unless otherwise specified.

The glass transition temperature (Tg) of the acrylic resin is preferably −60 to 70 ° C., more preferably −30 to 50 ° C. When the Tg of the acrylic resin is equal to or higher than the lower limit, the adhesive force between the protective film and the support sheet is suppressed, and the peelability of the support sheet is improved. Moreover, the adhesive force with the to-be-adhered body of the thermosetting protective film formation film and a protective film improves because Tg of acrylic resin is below the said upper limit.
In the present specification, the “glass transition temperature (Tg)” is represented by the temperature of the inflection point of the DSC curve obtained by measuring the DSC curve of the sample using a differential scanning calorimeter.

The acrylic resin is selected from, for example, a polymer of one or more (meth) acrylic acid esters; (meth) acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, N-methylolacrylamide, and the like. Examples include copolymers of two or more monomers.

Examples of the (meth) acrylic acid ester constituting the acrylic resin include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, (meth ) N-butyl acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, (meth) acrylic Heptyl acid, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, n-octyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate , Undecyl (meth) acrylate, dodecyl (meth) acrylate ((meth) acrylic acid (Also known as uril), tridecyl (meth) acrylate, tetradecyl (meth) acrylate (also referred to as myristyl (meth) acrylate), pentadecyl (meth) acrylate, hexadecyl (meth) acrylate (also known as palmityl (meth) acrylate) The alkyl group constituting the alkyl ester such as heptadecyl (meth) acrylate and octadecyl (meth) acrylate (also referred to as stearyl (meth) acrylate) has a chain structure having 1 to 18 carbon atoms. (Meth) acrylic acid alkyl ester;
(Meth) acrylic acid cycloalkyl esters such as (meth) acrylic acid isobornyl, (meth) acrylic acid dicyclopentanyl;
(Meth) acrylic acid aralkyl esters such as (meth) acrylic acid benzyl;
(Meth) acrylic acid cycloalkenyl esters such as (meth) acrylic acid dicyclopentenyl ester;
(Meth) acrylic acid cycloalkenyloxyalkyl esters such as (meth) acrylic acid dicyclopentenyloxyethyl ester;
(Meth) acrylic imide;
Glycidyl group-containing (meth) acrylic acid ester such as glycidyl (meth) acrylate;
Hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, (meta ) Hydroxyl group-containing (meth) acrylic acid esters such as 3-hydroxybutyl acrylate and 4-hydroxybutyl (meth) acrylate;
Examples thereof include substituted amino group-containing (meth) acrylic acid esters such as N-methylaminoethyl (meth) acrylate. Here, the “substituted amino group” means a group formed by replacing one or two hydrogen atoms of an amino group with a group other than a hydrogen atom.

The acrylic resin is, for example, one or more monomers selected from (meth) acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, N-methylolacrylamide and the like in addition to the (meth) acrylic ester. May be obtained by copolymerization.

The monomer constituting the acrylic resin may be only one type or two or more types. When there are two or more monomers constituting the acrylic resin, their combination and ratio can be arbitrarily selected.

The acrylic resin may have a functional group that can be bonded to other compounds such as a vinyl group, a (meth) acryloyl group, an amino group, a hydroxyl group, a carboxy group, and an isocyanate group. The functional group of the acrylic resin may be bonded to another compound via a cross-linking agent (F) described later, or may be directly bonded to another compound not via the cross-linking agent (F). . When the acrylic resin is bonded to another compound through the functional group, the reliability of the package obtained using the composite sheet for forming a protective film tends to be improved.

In the present invention, as the polymer component (A), a thermoplastic resin other than the acrylic resin (hereinafter sometimes simply referred to as “thermoplastic resin”) may be used in combination with the acrylic resin.
By using the thermoplastic resin, the peelability of the protective film from the support sheet is improved, and the film for forming the thermosetting protective film can easily follow the uneven surface of the adherend. Generation of voids and the like may be further suppressed between the protective film-forming film.

The weight average molecular weight of the thermoplastic resin is preferably 1000 to 100,000, more preferably 3000 to 80,000.

The glass transition temperature (Tg) of the thermoplastic resin is preferably −30 to 150 ° C., and more preferably −20 to 120 ° C.

Examples of the thermoplastic resin include polyester, polyurethane, phenoxy resin, polybutene, polybutadiene, and polystyrene.

The thermoplastic resin contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be only one kind or two or more kinds. When the said thermoplastic resin is 2 or more types, those combinations and ratios can be selected arbitrarily.

In the protective film forming composition (III-1), the polymer component (A) with respect to the total content of all components other than the solvent (also referred to as the total mass of the solid content of the protective film forming composition (III-1)) ) Content ratio (that is, the content of the polymer component (A) of the thermosetting protective film-forming film) is 5 to 50% by mass regardless of the type of the polymer component (A). Is preferable, 10 to 40% by mass is more preferable, and 15 to 35% by mass is particularly preferable.

The polymer component (A) may also correspond to the thermosetting component (B). In the present invention, when the protective film-forming composition (III-1) contains components corresponding to both the polymer component (A) and the thermosetting component (B), the protective film-forming composition is used. The composition (III-1) is considered to contain a polymer component (A) and a thermosetting component (B).

[Thermosetting component (B)]
The thermosetting component (B) is a component for curing a thermosetting protective film-forming film to form a hard protective film.
The thermosetting component (B) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one kind or two or more kinds. When there are two or more thermosetting components (B), their combination and ratio can be arbitrarily selected.

Examples of the thermosetting component (B) include epoxy thermosetting resins, thermosetting polyimides, polyurethanes, unsaturated polyesters, and silicone resins, and epoxy thermosetting resins are preferable.

(Epoxy thermosetting resin)
The epoxy thermosetting resin includes an epoxy resin (B1) and a thermosetting agent (B2).
The epoxy thermosetting resin contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be only one type or two or more types. When there are two or more epoxy thermosetting resins, their combination and ratio can be arbitrarily selected.

・ Epoxy resin (B1)
Examples of the epoxy resin (B1) include known ones such as polyfunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ether and hydrogenated products thereof, orthocresol novolac epoxy resins, dicyclopentadiene type epoxy resins, Biphenyl type epoxy resins, bisphenol A type epoxy resins, bisphenol F type epoxy resins, phenylene skeleton type epoxy resins, and the like, and bifunctional or higher functional epoxy compounds are listed.

As the epoxy resin (B1), an epoxy resin having an unsaturated hydrocarbon group may be used. An epoxy resin having an unsaturated hydrocarbon group is more compatible with an acrylic resin than an epoxy resin having no unsaturated hydrocarbon group. Therefore, the reliability of the package obtained using the composite sheet for forming a protective film is improved by using an epoxy resin having an unsaturated hydrocarbon group.

Examples of the epoxy resin having an unsaturated hydrocarbon group include compounds obtained by converting a part of the epoxy group of a polyfunctional epoxy resin into a group having an unsaturated hydrocarbon group. Such a compound can be obtained, for example, by addition reaction of (meth) acrylic acid or a derivative thereof to an epoxy group.
Moreover, as an epoxy resin which has an unsaturated hydrocarbon group, the compound etc. which the group which has an unsaturated hydrocarbon group directly couple | bonded with the aromatic ring etc. which comprise an epoxy resin are mentioned, for example.
The unsaturated hydrocarbon group is a polymerizable unsaturated group, and specific examples thereof include an ethenyl group (also referred to as a vinyl group), a 2-propenyl group (also referred to as an allyl group), and a (meth) acryloyl group. , (Meth) acrylamide groups and the like, and an acryloyl group is preferred.
In the present specification, the “derivative” means one obtained by substituting one or more hydrogen atoms of the original compound with a group (substituent) other than a hydrogen atom.

The number average molecular weight of the epoxy resin (B1) is not particularly limited, but is 300 to 30000 from the viewpoint of the curability of the thermosetting protective film-forming film and the strength and heat resistance of the cured protective film. Preferably, it is 300 to 10,000, more preferably 300 to 3000.
In the present specification, the “number average molecular weight” means a number average molecular weight represented by a standard polystyrene equivalent value measured by a gel permeation chromatography (GPC) method unless otherwise specified.
The epoxy equivalent of the epoxy resin (B1) is preferably 100 to 1100 g / eq, and more preferably 150 to 1000 g / eq.
In the present specification, the “epoxy equivalent” means the number of grams (g / eq) of an epoxy compound containing 1 gram equivalent of an epoxy group, and can be measured according to the method of JIS K 7236: 2001.

The epoxy resin (B1) may be used alone or in combination of two or more. When using 2 or more types of epoxy resins (B1) together, those combinations and ratios can be arbitrarily selected.

・ Thermosetting agent (B2)
The thermosetting agent (B2) functions as a curing agent for the epoxy resin (B1).
As a thermosetting agent (B2), the compound which has 2 or more of functional groups which can react with an epoxy group in 1 molecule is mentioned, for example. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxy group, a group in which an acid group has been anhydrideized, and the like, and a phenolic hydroxyl group, an amino group, or an acid group has been anhydrideized. It is preferably a group, more preferably a phenolic hydroxyl group or an amino group.

Among the thermosetting agents (B2), examples of the phenolic curing agent having a phenolic hydroxyl group include polyfunctional phenolic resins, biphenols, novolac-type phenolic resins, dicyclopentadiene-based phenolic resins, and aralkylphenolic resins.
Among the thermosetting agents (B2), examples of the amine-based curing agent having an amino group include dicyandiamide (hereinafter sometimes abbreviated as “DICY”).

The thermosetting agent (B2) may have an unsaturated hydrocarbon group.
Examples of the thermosetting agent (B2) having an unsaturated hydrocarbon group include compounds in which a part of the hydroxyl group of the phenol resin is substituted with a group having an unsaturated hydrocarbon group, and the aromatic ring of the phenol resin. Examples thereof include compounds in which a group having a saturated hydrocarbon group is directly bonded.
The unsaturated hydrocarbon group in the thermosetting agent (B2) is the same as the unsaturated hydrocarbon group in the epoxy resin having the unsaturated hydrocarbon group described above.

When using a phenolic curing agent as the thermosetting agent (B2), it is preferable that the thermosetting agent (B2) has a high softening point or glass transition temperature in terms of improving the peelability of the protective film from the support sheet. .

The thermosetting agent (B2) is a solid that is solid at normal temperature and does not exhibit curing activity with respect to the epoxy resin (B1), while it is dissolved by heating and exhibits curing activity with respect to the epoxy resin (B1). It is preferably a curing agent (hereinafter sometimes abbreviated as “thermally active latent epoxy resin curing agent”).
The thermoactive latent epoxy resin curing agent is stably dispersed in the epoxy resin (B1) in the thermosetting protective film-forming film at room temperature, but is compatible with the epoxy resin (B1) by heating. Reacts with the epoxy resin (B1). By using the thermally active latent epoxy resin curing agent, the storage stability of the protective film-forming composite sheet is significantly improved. For example, the movement of the curing agent from the protective film-forming film to the adjacent support sheet is suppressed, and the thermosetting deterioration of the thermosetting protective film-forming film is effectively suppressed. And since the thermosetting property by heating of the film for thermosetting protective film formation becomes higher, the pick-up property of the semiconductor chip with a protective film mentioned later improves more.

Examples of the thermally active latent epoxy resin curing agent include onium salts, dibasic acid hydrazides, dicyandiamide, and amine adducts of curing agents.

Among the thermosetting agents (B2), for example, the number average molecular weight of resin components such as polyfunctional phenolic resin, novolac-type phenolic resin, dicyclopentadiene-based phenolic resin, aralkylphenolic resin, etc. is preferably 300 to 30000, It is more preferably 400 to 10,000, and particularly preferably 500 to 3000.
Among the thermosetting agents (B2), for example, the molecular weight of non-resin components such as biphenol and dicyandiamide is not particularly limited, but is preferably 60 to 500, for example.

A thermosetting agent (B2) may be used individually by 1 type, and may use 2 or more types together. When using 2 or more types of thermosetting agents (B2) together, those combinations and ratios can be selected arbitrarily.

In the protective film-forming composition (III-1) and the thermosetting protective film-forming film, the content of the thermosetting agent (B2) is 0. 0 parts by mass with respect to 100 parts by mass of the epoxy resin (B1). The amount is preferably 1 to 500 parts by mass, and more preferably 1 to 200 parts by mass. When the content of the thermosetting agent (B2) is equal to or higher than the lower limit value, the curing of the thermosetting protective film forming film more easily proceeds. Moreover, the moisture absorption rate of the film for thermosetting protective film formation was reduced because the said content of the thermosetting agent (B2) was below the said upper limit, and it was obtained using the composite sheet for protective film formation Improved package reliability.

In the protective film forming composition (III-1) and the thermosetting protective film forming film, the content of the thermosetting component (B) (for example, the total content of the epoxy resin (B1) and the thermosetting agent (B2)) The amount is preferably 1 to 100 parts by weight, more preferably 1.5 to 85 parts by weight with respect to 100 parts by weight of the polymer component (A). It is particularly preferred that When the content of the thermosetting component (B) is in such a range, the adhesive force between the protective film and the support sheet is suppressed, and the peelability of the support sheet is improved.

[Curing accelerator (C)]
The protective film-forming composition (III-1) and the thermosetting protective film-forming film may contain a curing accelerator (C). The curing accelerator (C) is a component for adjusting the curing rate of the protective film-forming composition (III-1).
Preferred curing accelerators (C) include, for example, tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol; 2-methylimidazole, 2-phenylimidazole Imidazoles such as 2-phenyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole (one or more hydrogen atoms are other than hydrogen atoms) Organic phosphines such as tributylphosphine, diphenylphosphine, triphenylphosphine (also referred to as phosphine in which one or more hydrogen atoms are substituted with organic groups); tetraphenylphosphonium tetra Eniruboreto, tetraphenyl boron salts such as triphenyl phosphine tetraphenyl borate and the like.

The curing accelerator (C) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one kind or two or more kinds. When there are two or more curing accelerators (C), the combination and ratio thereof can be arbitrarily selected.

When the curing accelerator (C) is used, the content of the curing accelerator (C) in the protective film-forming composition (III-1) and the thermosetting protective film-forming film is such that the thermosetting component (B) The content is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass. The effect by using a hardening accelerator (C) is acquired more notably because the said content of a hardening accelerator (C) is more than the said lower limit. Moreover, since content of a hardening accelerator (C) is below the said upper limit, for example, a highly polar hardening accelerator (C) is in a film for thermosetting protective film formation under high temperature and high humidity conditions. In this case, the effect of suppressing the segregation by moving toward the adhesion interface with the adherend is increased, and the reliability of the package obtained using the composite sheet for forming a protective film is further improved.

[Filler (D)]
The protective film-forming composition (III-1) and the thermosetting protective film-forming film may contain a filler (D). When the thermosetting protective film-forming film contains the filler (D), the protective film obtained by curing the thermosetting protective film-forming film can easily adjust the thermal expansion coefficient. By optimizing the expansion coefficient with respect to the object for forming the protective film, the reliability of the package obtained using the composite sheet for forming the protective film is further improved. Moreover, the moisture absorption rate of a protective film can be reduced or heat dissipation can be improved because the film for thermosetting protective film formation contains a filler (D).

The filler (D) may be either an organic filler or an inorganic filler, but is preferably an inorganic filler.
Preferred inorganic fillers include, for example, powders of silica, alumina, talc, calcium carbonate, titanium white, bengara, silicon carbide, boron nitride, and the like; beads formed by spheroidizing these inorganic fillers; surface modification of these inorganic fillers Products; single crystal fibers of these inorganic fillers; glass fibers and the like.
Among these, the inorganic filler is preferably silica or alumina.

The filler (D) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be only one kind or two or more kinds. When there are two or more fillers (D), their combination and ratio can be arbitrarily selected.

When the filler (D) is used, the total content of all components other than the solvent in the protective film forming composition (III-1) (the total mass of the solid content of the protective film forming composition (III-1)) The ratio of the content of the filler (D) to the content of the filler (D) (that is, the content of the filler (D) of the thermosetting protective film-forming film) is preferably 5 to 80% by mass, More preferably, it is 60 mass%. Adjustment of said thermal expansion coefficient becomes easier because content of a filler (D) is such a range.

[Coupling agent (E)]
The protective film-forming composition (III-1) and the thermosetting protective film-forming film may contain a coupling agent (E). By using a coupling agent (E) having a functional group capable of reacting with an inorganic compound or an organic compound, the adhesion and adhesion of the thermosetting protective film-forming film to the adherend can be improved. it can. Moreover, by using the coupling agent (E), the protective film obtained by curing the thermosetting protective film-forming film has improved water resistance without impairing heat resistance.

The coupling agent (E) is preferably a compound having a functional group capable of reacting with the functional group of the polymer component (A), the thermosetting component (B), etc., and is preferably a silane coupling agent. More preferred.
Preferred examples of the silane coupling agent include 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxymethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3- (2-aminoethylamino) propyltrimethoxysilane, 3- (2-amino Ethylamino) propylmethyldiethoxysilane, 3- (phenylamino) propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropi Examples include trimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, bis (3-triethoxysilylpropyl) tetrasulfane, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, and imidazolesilane. It is done.

The coupling agent (E) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one kind or two or more kinds. When there are two or more coupling agents (E), the combination and ratio thereof can be arbitrarily selected.

When the coupling agent (E) is used, the content of the coupling agent (E) in the protective film-forming composition (III-1) and the thermosetting protective film-forming film is such that the polymer component (A) and The amount is preferably 0.03 to 20 parts by weight, more preferably 0.05 to 10 parts by weight, and more preferably 0.1 to 5 parts by weight with respect to 100 parts by weight as the total content of the thermosetting component (B). The part by mass is particularly preferred. When the content of the coupling agent (E) is equal to or more than the lower limit, the dispersibility of the filler (D) in the resin is improved, and the thermosetting protective film-forming film is adhered to the adherend. The effect by using a coupling agent (E), such as a property improvement, is acquired more notably. Moreover, generation | occurrence | production of an outgas is suppressed more because the said content of a coupling agent (E) is below the said upper limit.

[Crosslinking agent (F)]
As the polymer component (A), those having functional groups such as vinyl group, (meth) acryloyl group, amino group, hydroxyl group, carboxy group, isocyanate group and the like that can be bonded to other compounds such as the above-mentioned acrylic resin. When used, the protective film-forming composition (III-1) and the thermosetting protective film-forming film contain a crosslinking agent (F) for bonding the functional group with another compound to crosslink. Also good. By crosslinking using the crosslinking agent (F), the initial adhesive force and cohesive force of the thermosetting protective film-forming film can be adjusted.

Examples of the crosslinking agent (F) include an organic polyvalent isocyanate compound, an organic polyvalent imine compound, a metal chelate crosslinking agent (also referred to as a crosslinking agent having a metal chelate structure), and an aziridine crosslinking agent (a crosslinking agent having an aziridinyl group). Also).

Examples of the organic polyvalent isocyanate compound include an aromatic polyvalent isocyanate compound, an aliphatic polyvalent isocyanate compound, and an alicyclic polyvalent isocyanate compound (hereinafter, these compounds are collectively referred to as “aromatic polyvalent isocyanate compound and the like”). A trimer such as the aromatic polyisocyanate compound, isocyanurate and adduct; a terminal isocyanate urethane prepolymer obtained by reacting the aromatic polyvalent isocyanate compound and the polyol compound. Etc. The “adduct body” includes the aromatic polyisocyanate compound, the aliphatic polyisocyanate compound or the alicyclic polyisocyanate compound, and a low amount such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane or castor oil. It means a reaction product with a molecularly active hydrogen-containing compound, and examples thereof include an xylylene diisocyanate adduct of trimethylolpropane as described later. The “terminal isocyanate urethane prepolymer” is as described above.

More specifically, as the organic polyvalent isocyanate compound, for example, 2,4-tolylene diisocyanate; 2,6-tolylene diisocyanate; 1,3-xylylene diisocyanate; 1,4-xylene diisocyanate; diphenylmethane-4 Dimethylmethane-2,4'-diisocyanate; 3-methyldiphenylmethane diisocyanate; hexamethylene diisocyanate; isophorone diisocyanate; dicyclohexylmethane-4,4'-diisocyanate; dicyclohexylmethane-2,4'-diisocyanate; trimethylol Any one of tolylene diisocyanate, hexamethylene diisocyanate and xylylene diisocyanate is added to all or some hydroxyl groups of a polyol such as propane. Or two or more compounds are added; lysine diisocyanate.

Examples of the organic polyvalent imine compound include N, N′-diphenylmethane-4,4′-bis (1-aziridinecarboxamide), trimethylolpropane-tri-β-aziridinylpropionate, and tetramethylolmethane. -Tri-β-aziridinylpropionate, N, N′-toluene-2,4-bis (1-aziridinecarboxamide) triethylenemelamine and the like.

When an organic polyvalent isocyanate compound is used as the crosslinking agent (F), it is preferable to use a hydroxyl group-containing polymer as the polymer component (A). When the crosslinking agent (F) has an isocyanate group and the polymer component (A) has a hydroxyl group, a reaction between the crosslinking agent (F) and the polymer component (A) results in a thermosetting protective film forming film. A crosslinked structure can be easily introduced.

The crosslinking agent (F) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one kind or two or more kinds. When there are two or more crosslinking agents (F), their combination and ratio can be arbitrarily selected.

When the crosslinking agent (F) is used, the content of the crosslinking agent (F) in the protective film-forming composition (III-1) is 0. 0 parts by mass relative to 100 parts by mass of the polymer component (A). The amount is preferably 01 to 20 parts by mass, more preferably 0.1 to 10 parts by mass, and particularly preferably 0.5 to 5 parts by mass. The effect by using a crosslinking agent (F) is acquired more notably because the said content of a crosslinking agent (F) is more than the said lower limit. Moreover, because the content of the crosslinking agent (F) is not more than the upper limit value, the adhesive force with the support sheet of the thermosetting protective film forming film, the semiconductor wafer of the thermosetting protective film forming film, or It is suppressed that the adhesive force with a semiconductor chip falls too much.
In the present invention, the effects of the present invention can be sufficiently obtained without using the crosslinking agent (F).

[Energy ray curable resin (G)]
The protective film-forming composition (III-1) may contain an energy ray curable resin (G). Since the thermosetting protective film-forming film contains the energy ray-curable resin (G), the characteristics can be changed by irradiation with energy rays.

The energy beam curable resin (G) is obtained by polymerizing (curing) an energy beam curable compound.
Examples of the energy ray curable compound include compounds having at least one polymerizable double bond in the molecule, and acrylate compounds having a (meth) acryloyl group are preferable.

Examples of the acrylate compound include trimethylolpropane tri (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol monohydroxypenta ( Chain aliphatic skeleton-containing (meth) acrylates such as (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,4-butylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate; Cyclic aliphatic skeleton-containing (meth) acrylates such as cyclopentanyl di (meth) acrylate; polyalkylene glycol (meth) acrylates such as polyethylene glycol di (meth) acrylate Oligoester (meth) acrylate; urethane (meth) acrylate oligomer, epoxy-modified (meth) acrylate; the polyalkylene glycol (meth) Polyether (meth) acrylates other than the acrylates; itaconic acid oligomer, and the like.

The weight average molecular weight of the energy ray curable compound is preferably 100 to 30000, and more preferably 300 to 10000.

The energy ray curable compound used for polymerization may be only one kind or two or more kinds. When the energy ray curable compounds are two or more, the combination and ratio thereof can be arbitrarily selected.

The energy ray-curable resin (G) contained in the protective film-forming composition (III-1) may be only one type or two or more types. When energy beam curable resin (G) is 2 or more types, those combinations and ratios can be selected arbitrarily.

In the protective film-forming composition (III-1), the content of the energy ray-curable resin (G) is 1 to 95% by mass with respect to the total mass of the protective film-forming composition (III-1). It is preferably 2 to 90% by mass, more preferably 3 to 85% by mass.

[Photopolymerization initiator (H)]
When the protective film-forming composition (III-1) contains the energy beam curable resin (G), the photopolymerization initiator (H) is used to efficiently advance the polymerization reaction of the energy beam curable resin (G). ) May be contained.

Examples of the photopolymerization initiator (H) in the protective film-forming composition (III-1) include the same photopolymerization initiator as in the pressure-sensitive adhesive composition (I-1).

The photopolymerization initiator (H) contained in the protective film-forming composition (III-1) may be only one type or two or more types. When there are two or more photopolymerization initiators (H), their combination and ratio can be arbitrarily selected.

In the protective film-forming composition (III-1), the content of the photopolymerization initiator (H) is 0.1 to 20 parts by mass with respect to 100 parts by mass of the energy beam curable resin (G). It is preferably 1 to 10 parts by mass, more preferably 2 to 5 parts by mass.

[Colorant (I)]
The protective film-forming composition (III-1) and the thermosetting protective film-forming film may contain a colorant (I).
Examples of the colorant (I) include known pigments such as inorganic pigments, organic pigments, and organic dyes.

Examples of the organic pigments and organic dyes include aminium dyes, cyanine dyes, merocyanine dyes, croconium dyes, squalium dyes, azurenium dyes, polymethine dyes, naphthoquinone dyes, pyrylium dyes, and phthalocyanines. Dyes, naphthalocyanine dyes, naphtholactam dyes, azo dyes, condensed azo dyes, indigo dyes, perinone dyes, perylene dyes, dioxazine dyes, quinacridone dyes, isoindolinone dyes, quinophthalone dyes , Pyrrole dyes, thioindigo dyes, metal complex dyes (metal complex dyes), dithiol metal complex dyes, indolephenol dyes, triallylmethane dyes, anthraquinone dyes, naphthol dyes, azomethine dyes, benzimidazo B Systems dyes, pyranthrone pigments and threne color like.

Examples of the inorganic pigment include carbon black, cobalt dye, iron dye, chromium dye, titanium dye, vanadium dye, zirconium dye, molybdenum dye, ruthenium dye, platinum dye, ITO ( Indium tin oxide) dyes, ATO (antimony tin oxide) dyes, and the like.

The colorant (I) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one kind or two or more kinds. When there are two or more colorants (I), their combination and ratio can be arbitrarily selected.

When using the colorant (I), the content of the colorant (I) in the thermosetting protective film-forming film may be appropriately adjusted according to the purpose. For example, the protective film may be printed by laser irradiation, adjusting the content of the colorant (I) of the thermosetting protective film-forming film, and adjusting the light transmittance of the protective film, Print visibility can be adjusted. In addition, by adjusting the content of the colorant (I) in the thermosetting protective film-forming film, it is possible to improve the design of the protective film and make it difficult to see the grinding marks on the back surface of the semiconductor wafer. Considering these points, the total content of all components other than the solvent in the protective film-forming composition (III-1) (also referred to as the total solid content of the protective film-forming composition (III-1)) The ratio of the content of the colorant (I) relative to the colorant (i.e., the content of the colorant (I) in the thermosetting protective film-forming film) is preferably 0.1 to 10% by mass. The content is more preferably 1 to 7.5% by mass, and particularly preferably 0.1 to 5% by mass. When the content of the colorant (I) is equal to or more than the lower limit value, the effect of using the colorant (I) is more remarkably obtained. Moreover, the excessive fall of the light transmittance of the film for thermosetting protective film formation is suppressed because the said content of a coloring agent (I) is below the said upper limit.

[General-purpose additive (J)]
The protective film-forming composition (III-1) and the thermosetting protective film-forming film may contain a general-purpose additive (J) as long as the effects of the present invention are not impaired.
The general-purpose additive (J) may be a known one and can be arbitrarily selected according to the purpose, and is not particularly limited. Preferred examples include a plasticizer, an antistatic agent, an antioxidant, a gettering agent, and the like. Is mentioned.

The general-purpose additive (J) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be only one kind or two or more kinds. When there are two or more general-purpose additives (J), their combination and ratio can be arbitrarily selected.
The content of the general-purpose additive (J) in the protective film-forming composition (III-1) and the thermosetting protective film-forming film is not particularly limited, and may be appropriately selected depending on the purpose.

[solvent]
The composition for forming a protective film (III-1) preferably further contains a solvent. The protective film-forming composition (III-1) containing a solvent has good handleability.
The solvent is not particularly limited, but preferred examples include hydrocarbons such as toluene and xylene; methanol, ethanol, 2-propanol, isobutyl alcohol (also referred to as 2-methylpropan-1-ol), 1-butanol and the like. Alcohols; esters such as ethyl acetate and butyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; amides such as dimethylformamide and N-methylpyrrolidone (also referred to as compounds having an amide bond).
The solvent contained in the protective film-forming composition (III-1) may be only one type or two or more types. When two or more solvents are used, their combination and ratio can be arbitrarily selected.

The solvent contained in the protective film-forming composition (III-1) is preferably methyl ethyl ketone or the like from the viewpoint that the components in the protective film-forming composition (III-1) can be more uniformly mixed.

<< Method for Producing Thermosetting Protective Film Forming Composition >>
A thermosetting protective film-forming composition such as the protective film-forming composition (III-1) can be obtained by blending each component for constituting the composition.
The order of addition at the time of blending each component is not particularly limited, and two or more components may be added simultaneously.
When a solvent is used, it may be used by mixing the solvent with any compounding component other than the solvent and diluting the compounding component in advance, or by diluting any compounding component other than the solvent in advance. You may use it by mixing a solvent with these compounding ingredients, without leaving.
The method of mixing each component at the time of compounding is not particularly limited, from a known method such as a method of mixing by rotating a stirrer or a stirring blade; a method of mixing using a mixer; a method of mixing by applying ultrasonic waves What is necessary is just to select suitably.
The temperature and time during the addition and mixing of each component are not particularly limited as long as each compounding component does not deteriorate, and may be adjusted as appropriate, but the temperature is preferably 15 to 30 ° C.

Similar to the protective film-forming composite sheet of the present invention, it is affixed to the back surface opposite to the circuit surface of the semiconductor wafer or semiconductor chip, and as a composite sheet provided with a layer showing adhesion on the support sheet. There is a dicing die bonding sheet.
However, the adhesive layer provided in the dicing die bonding sheet functions as an adhesive when the semiconductor chip is picked up from the support sheet together with the semiconductor chip and then attached to the substrate, the lead frame, or another semiconductor chip. On the other hand, the protective film-forming film in the protective film-forming composite sheet of the present invention is the same as the adhesive layer in that it is picked up from the support sheet together with the semiconductor chip, but eventually becomes a protective film by curing, It has a function of protecting the back surface of the semiconductor chip that is affixed. Thus, the protective film-forming film in the present invention has a different use from the adhesive layer in the dicing die bonding sheet, and naturally the required performance is also different. Reflecting this difference in use, the protective film-forming film is usually harder and more difficult to pick up than the adhesive layer in the dicing die bonding sheet. Therefore, it is usually difficult to divert the adhesive layer in the dicing die bonding sheet as it is as the protective film-forming film in the protective film-forming composite sheet. The composite sheet for forming a protective film of the present invention is required to have an excellent pickability of a semiconductor chip with a protective film as a film provided with a thermosetting protective film-forming film.

◇ Method for Producing Protective Film-Forming Composite Sheet The protective film-forming composite sheet of the present invention can be produced by sequentially laminating the above-mentioned layers so as to have a corresponding positional relationship. The method for forming each layer is as described above.
For example, when a pressure-sensitive adhesive layer is laminated on a substrate when producing a support sheet, the above-described pressure-sensitive adhesive composition may be applied on the substrate and dried as necessary.

On the other hand, for example, when a protective film-forming film is further laminated on the adhesive layer laminated on the substrate, the protective film-forming composition is applied on the adhesive layer, It is possible to form the forming film directly. Layers other than the protective film-forming film can also be laminated on the pressure-sensitive adhesive layer in the same manner using the composition for forming this layer. As described above, when a continuous two-layer laminated structure is formed using any of the compositions, the composition is further applied onto the layer formed from the composition to newly form a layer. Can be formed.
However, the layer laminated after these two layers is formed in advance using the composition on another release film, and the side of the formed layer that is in contact with the release film is It is preferable to form a continuous two-layer laminated structure by bonding the opposite exposed surface to the exposed surfaces of the remaining layers already formed. At this time, the composition is preferably applied to the release-treated surface of the release film. The release film may be removed as necessary after forming the laminated structure.

For example, a protective film-forming composite sheet in which a pressure-sensitive adhesive layer is laminated on a base material and a protective film-forming film is laminated on the pressure-sensitive adhesive layer (the support sheet is a laminate of the base material and the pressure-sensitive adhesive layer) In the case of producing a protective sheet-forming composite sheet), a pressure-sensitive adhesive composition is coated on a base material and dried as necessary, whereby a pressure-sensitive adhesive layer is laminated on the base material, The protective film-forming composition is coated on the release film, and dried as necessary to form the protective film-forming film on the release film. Then, the exposed surface of the protective film-forming film is bonded to the exposed surface of the adhesive layer laminated on the substrate, and the protective film-forming film is laminated on the adhesive layer, thereby forming a protective film. A composite sheet is obtained.

In addition, when laminating the pressure-sensitive adhesive layer on the substrate, as described above, instead of the method of coating the pressure-sensitive adhesive composition on the substrate, the pressure-sensitive adhesive composition is applied on the release film. The pressure-sensitive adhesive layer is formed on the release film by drying as necessary, and the exposed surface of this layer is bonded to one surface of the base material so that the pressure-sensitive adhesive layer is placed on the base material. You may laminate.
In any method, the release film may be removed at an arbitrary timing after the target laminated structure is formed.

In this way, all layers other than the base material constituting the protective film-forming composite sheet can be formed in advance on the release film and laminated on the surface of the target layer. A layer that employs such a process may be appropriately selected to produce a protective sheet-forming composite sheet.

In addition, the composite sheet for forming a protective film is usually stored in a state in which a release film is bonded to the surface of the outermost layer (for example, a film for forming a protective film) opposite to the support sheet. Therefore, a composition for forming a layer constituting the outermost layer, such as a protective film-forming composition, is applied on this release film (preferably its release-treated surface) and dried as necessary. Then, a layer constituting the outermost layer is formed on the release film, and the remaining layers are laminated on the exposed surface of the layer opposite to the side in contact with the release film by any of the methods described above. And the composite sheet for protective film formation is obtained also by leaving it in the state bonded together, without removing a peeling film.

Manufacturing method of semiconductor chip with protective film The manufacturing method of a semiconductor chip with protective film according to the present invention is a method of laminating a semiconductor wafer on the thermosetting protective film forming film side of the protective film forming composite sheet. A process of making a body,
Irradiating a semiconductor wafer with laser light to form a modified layer inside the semiconductor wafer; and
Cool expanding the laminate at a temperature lower than room temperature, and dividing the semiconductor wafer and the thermosetting protective film forming film,
And heat curing the thermosetting protective film-forming film of the laminate to form a protective film.

In the method for manufacturing a semiconductor chip with a protective film according to the present invention, after the step of laminating a semiconductor wafer on the thermosetting protective film forming film side of the protective film forming composite sheet to form a laminate, the semiconductor wafer Forming a modified layer inside the semiconductor wafer by irradiating the inside of the semiconductor wafer, and forming the semiconductor wafer and the thermosetting protective film by cool expanding the laminate at a temperature lower than room temperature You may provide in this order the process of dividing | segmenting the film for heat | fever, and the process of heat-curing the said film for thermosetting protective film formation of the said laminated body to make a protective film. An example of the manufacturing method of this semiconductor chip with a protective film will be described with reference to FIG.

FIG. 3 is a cross-sectional view schematically showing an example of a method for manufacturing a semiconductor chip with a protective film.
First, after grinding the back surface of the semiconductor wafer 18 to a desired thickness, affixing the back surface of the semiconductor wafer 18 after back grinding to the thermosetting protective film forming film 23 of the protective film forming composite sheet 2, The composite sheet 2 for forming a protective film is fixed to the ring frame 17 (FIG. 3A). When the back grind tape 20 is stuck on the surface (electrode formation surface) of the semiconductor wafer 18, the back grind tape 20 is removed from the semiconductor wafer 18.

Next, the modified layer 18 c is formed inside the semiconductor wafer 18 by irradiating the laser beam from the side of the protective film forming composite sheet 2 so as to be focused on the focal point set inside the semiconductor wafer 18 (SD). (FIG. 3B). Further, laser printing is performed by irradiating laser light from the support sheet 10 side as necessary.

Next, the semiconductor wafer 18 is moved to a low-temperature environment together with the protective film-forming composite sheet 2 attached to the back surface, and is subjected to cool expansion (CE) in the plane direction of the protective film-forming composite sheet 2 to form a thermosetting protective film. While cleaving the forming film, the semiconductor wafer 18 is divided at the portion of the modified layer 18c and separated into individual pieces (FIG. 3C). The temperature condition of the cool expand (CE) may be any temperature lower than room temperature, but is preferably −20 to 10 ° C., more preferably −15 to 5 ° C. Infrared inspection is performed by irradiating infrared laser light from the support sheet 10 side as necessary.

Further, if necessary, a sub ring may be attached to the expanded support sheet 10 (that is, the base material 11 and the adhesive layer 12), and the support sheet 10 may be fixed while being expanded. Alternatively, the base sheet 11 is used by imparting heat shrinkability (heat shrinkability) to the support sheet 10 and then using the heat shrinkability (heat shrinkability) of the base material 11 to cool the support sheet 10. The support sheet 10 can be fixed in an expanded state without attaching a sub-ring except for the slack of the sheet 10. When the adhesive layer 12 is energy ray curable, the adhesive layer 12 is cured by irradiation of energy rays after fixing the expanded support sheet 10 by attaching a sub ring or the like, After the pressure-sensitive adhesive layer 12 is cured, it is preferable to move to the next step of curing the thermosetting protective film-forming film 23.

Furthermore, the laminated body of the support sheet 10, the separated thermosetting protective film forming film 23, and the separated semiconductor chip 19 is heated to cure the thermosetting protective film forming film 23. Thus, the protective film 23 ′ is obtained (FIG. 3D).

The composite film 2 for forming a protective film whose pickup suitability described later is suitably adjusted is usually obtained by a cool expand (CE) at a temperature lower than room temperature, and the adhesive layer 12 and the thermosetting protective film-forming film 23. The float between will occur. However, the protective sheet-forming composite sheet 2 of the present invention has a storage elastic modulus (G ′ (70)) at 70 ° C. of the pressure-sensitive adhesive layer 12 of 0.16 MPa or less, preferably 0.15 MPa or less, More preferably, it is 0.10 MPa or less, and particularly preferably 0.06 MPa or less, so that the float tends to disappear under the conditions of thermosetting of the thermosetting protective film-forming film 23, so that no float marks remain. be able to.

In the composite sheet for forming a protective film of the present invention, the storage elastic modulus (G ′ (70)) at 70 ° C. of the pressure-sensitive adhesive layer is preferably 0.01 MPa or more, particularly preferably 0.02 MPa or more. Thereby, at the time of thermosetting the thermosetting protective film forming film 23, the pressure-sensitive adhesive layer 12 is too soft and does not protrude from the end.

Finally, the semiconductor chip 19 with the protective film 23 ′ is obtained by peeling the semiconductor chip 19 from the support sheet 10 together with the protective film 23 ′ pasted on the back surface thereof to pick up the semiconductor chip 19 (FIG. 3E). When the pressure-sensitive adhesive layer 12 is energy-ray curable, the pressure-sensitive adhesive layer 12 is cured by irradiation with energy rays as necessary, and the semiconductor chip 19 is placed on the back surface of the cured pressure-sensitive adhesive layer 12. By picking up with the attached protective film 23 ', the semiconductor chip 19 with the protective film 23' can be obtained more easily.

FIG. 3 illustrates an example of a method of manufacturing a semiconductor chip with a protective film using the protective film-forming composite sheet 2 having the jig adhesive layer 16, but the jig adhesive layer 16 is provided. The example of the manufacturing method of the semiconductor chip with a protective film using the composite sheet 1 for protective film formation which is not present is also the same.

In FIG. 3, a laser beam is irradiated from the side of the protective film forming composite sheet 2 so as to be focused on a focal point set inside the semiconductor wafer 18 (SD), and the modified layer is formed inside the semiconductor wafer 18. However, the present invention is not limited to this, and includes the step of forming the modified layer, the step of forming the laminate, the step of dividing, and the step of forming the protective film in this order. Specifically, for example, a modified layer is formed inside the semiconductor wafer 18 to which the back grind tape 20 is stuck, and the protective film-forming composite sheet 2 is formed on the semiconductor wafer 18 on which the modified layer is formed. May be affixed. Thereafter, the semiconductor sheet 19 with the protective film 23 ′ is obtained by irradiating laser light from the side of the support sheet 10, performing laser printing, and performing cool expansion (CE), thermosetting, infrared inspection, and picking up.

◎ Manufacturing method of semiconductor device Thereafter, the semiconductor chip with the protective film obtained by the same method as the conventional method is flip-chip connected to the circuit surface of the substrate with the protective film attached, and then the semiconductor A package. Then, a target semiconductor device may be manufactured using this semiconductor package.

One aspect of the present invention is that the composite sheet for forming a protective film has a three-layer transparent film (thickness: 60 to 150 μm) made of a mixed resin of polypropylene (PP) and olefinic thermoplastic elastomer (TPO) as a base material. An adhesive layer (thickness: 3 to 20 μm, storage elastic modulus at 70 ° C. of 0.01 to 0.06 MPa, and a Young's modulus of 1 to 100 MPa at 23 ° C., and The pressure-sensitive adhesive composition (polymer component: (meth) acrylic acid ester copolymer (2-ethylhexyl acrylate (2EHA) 70-80 parts by mass), A copolymer obtained by copolymerizing 20 to 30 parts by mass of hydroxylethyl acrylate (HEA. Weight average molecular weight: 70 to 900,000) 100 parts by mass and a crosslinking agent component: 3 A non-energy ray-curable pressure-sensitive adhesive composition containing 20 parts by mass of a functional xylene diisocyanate-based crosslinking agent); a thermosetting protective film-forming film (thickness: 5 to 50 μm); (Polymer component: acrylic polymer obtained by copolymerizing 80 to 90 parts by mass of methyl acrylate and 10 to 20 parts by mass of 2-hydroxyethyl acrylate (weight average molecular weight: 30 to 450,000, Tg: 1 to 10 ° C.) 150 parts by mass, epoxy resin (bisphenol A type epoxy resin (epoxy equivalent 184 to 194 g / eq) 60 parts by mass, bisphenol A type epoxy resin (epoxy equivalent 800 to 900 g / eq) 10 parts by mass, dicyclopentadiene type epoxy resin (Epoxy equivalent 255-260 g / eq) 30 parts by mass) and a curing agent (dicyandiamide (active hydrogen) 21 g / eq)) 2 parts by mass, 2 parts by mass of a curing accelerator (2-phenyl-4,5-dihydroxymethylimidazole), 320 parts by mass of a filler (silica filler (average particle size 0.5 μm)), A protective film-forming composition containing 2 parts by mass of a coupling agent (silane coupling agent) and 18 parts by mass of a colorant (black pigment).

In another aspect of the present invention, the composite sheet for forming a protective film has a three-layer transparent film (thickness: 80 μm, 23) made of a mixed resin of polypropylene (PP) and olefinic thermoplastic elastomer (TPO) as a base material. Young's modulus at 50 ° C., matte surface / gloss surface substrate); pressure-sensitive adhesive layer (thickness: 5 μm, storage elastic modulus at 70 ° C. is 0.03 MPa, and storage elastic modulus at 23 ° C. is 0.31 MPa ) And a pressure-sensitive adhesive composition (polymer component: (meth) acrylic acid ester copolymer (2-ethylhexyl acrylate (2EHA) 80 parts by mass, 2-hydroxylethyl acrylate (HEA) 20 parts by mass) Copolymer, containing 100 parts by mass of weight average molecular weight: 800,000) and 20 parts by mass of a crosslinking agent component: trifunctional xylene diisocyanate-based crosslinking agent Non-energy ray-curable pressure-sensitive adhesive composition); a thermosetting protective film-forming film (thickness: 25 μm), and a protective film-forming composition (polymer component: 85 parts by mass of methyl acrylate, 2-hydroxyethyl 150 parts by mass of an acrylic polymer obtained by copolymerizing 15 parts by mass of acrylate (weight average molecular weight: 370,000, Tg: 6 ° C.), and epoxy resin (bisphenol A type epoxy resin (epoxy equivalent 184 to 194 g / eq) 60) Parts by weight, bisphenol A type epoxy resin (epoxy equivalent 800-900 g / eq) 10 parts by mass, dicyclopentadiene type epoxy resin (epoxy equivalent 255-260 g / eq) 30 parts by mass) and curing agent (dicyandiamide (active hydrogen content) 21 g / eq)) 2 parts by weight and a curing accelerator (2-phenyl-4,5-dihydroxymethylimi Sol) 2 parts by mass, filler (silica filler (average particle size 0.5 μm)) 320 parts by mass, coupling agent (silane coupling agent) 2 parts by mass, colorant (black pigment) 18 parts by mass, A composition for forming a protective film).

Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the present invention is not limited to the following examples.

(Production of protective film-forming composition (III-1))
The components used for the production of the protective film-forming composition are shown below.
Polymer component (a): acrylic polymer obtained by copolymerization of 85 parts by mass of methyl acrylate and 15 parts by mass of 2-hydroxyethyl acrylate (weight average molecular weight: 370,000, Tg: 6 ° C.)
Epoxy resin (b1) -1: Bisphenol A type epoxy resin (Mitsubishi Chemical Corporation jER828, epoxy equivalent 184 to 194 g / eq)
(B1) -2: Bisphenol A type epoxy resin (Mitsubishi Chemical Corporation jER1055, epoxy equivalent 800-900 g / eq)
(B1) -3: a dicyclopentadiene type epoxy resin (Epiclon HP-7200HH, manufactured by DIC, epoxy equivalent of 255 to 260 g / eq)
・ Curing agent
(B2): Dicyandiamide (manufactured by ADEKA, Adeka Hardener EH-3636AS, active hydrogen amount 21 g / eq))
・ Curing accelerator
(C): 2-phenyl-4,5-dihydroxymethylimidazole (Curesol 2PHZ manufactured by Shikoku Kasei Kogyo Co., Ltd.)
Filler (d) Silica filler (SC2050MA average particle size 0.5 μm manufactured by Admatechs)
Coupling agent (e): Silane coupling agent (Nihon Unicar A-1110)
-Colorant (i): Black pigment (manufactured by Dainichi Seika Kogyo)

Polymer component (a), epoxy resin (b1) -1, epoxy resin (b1) -2, epoxy resin (b1) -3, curing agent (b2), curing accelerator (c), filler (d), The coupling agent (e) and the colorant (i) have a content (solid content, part by mass) of 150/60/10/30/2/2/320/2/18 (solid weight ratio). Thus, the composition (III-1) for forming a protective film having a solid content concentration of 52% by mass was prepared by dissolving or dispersing in methyl ethyl ketone and stirring at 23 ° C.

(Production of pressure-sensitive adhesive composition (I-4-1))
-Polymer component (A1): (meth) acrylic acid ester copolymer (copolymer obtained by copolymerizing 80 parts by mass of 2-ethylhexyl acrylate (2EHA) and 20 parts by mass of 2-hydroxylethyl acrylate (HEA) (Weight average molecular weight: 800,000)
Crosslinking agent component (C): Trifunctional xylene diisocyanate crosslinking agent (trade name “Takenate (registered trademark) D-110N” manufactured by Mitsui Takeda Chemical Co., Ltd.)

It contains a polymer component (A1) (100 parts by mass, solid content) and a crosslinking agent component (C) (20 parts by mass, solid content), and further contains methyl ethyl ketone as a solvent. A non-energy ray curable pressure-sensitive adhesive composition (I-4-1) was prepared.

(Production of pressure-sensitive adhesive composition (I-4-2))
-Polymer component (A1): (meth) acrylic acid ester copolymer (copolymer obtained by copolymerizing 80 parts by mass of 2-ethylhexyl acrylate (2EHA) and 20 parts by mass of 2-hydroxylethyl acrylate (HEA) (Weight average molecular weight: 800,000)
Crosslinking agent component (C): Trifunctional xylene diisocyanate crosslinking agent (trade name “Takenate (registered trademark) D-110N” manufactured by Mitsui Takeda Chemical Co., Ltd.)

It contains a polymer component (A1) (100 parts by mass, solid content) and a crosslinking agent component (C) (1 part by mass, solid content), and further contains methyl ethyl ketone as a solvent. A non-energy ray curable pressure-sensitive adhesive composition (I-4-2) was prepared.

(Production of pressure-sensitive adhesive composition (I-4-3))
Polymer component (A1): (meth) acrylic acid ester copolymer (2-ethylhexyl acrylate (2EHA) 60 parts by mass, methyl methacrylate (MMA) 30 parts by mass, 2-hydroxylethyl acrylate (HEA) 10 parts by mass Copolymer obtained by copolymerization of (weight average molecular weight: 800,000)
Crosslinking agent component (C): Trifunctional xylene diisocyanate crosslinking agent (trade name “Takenate (registered trademark) D-110N” manufactured by Mitsui Takeda Chemical Co., Ltd.)

It contains a polymer component (A1) (100 parts by mass, solid content) and a crosslinking agent component (C) (20 parts by mass, solid content), and further contains methyl ethyl ketone as a solvent. A non-energy ray curable pressure-sensitive adhesive composition (I-4-3) was prepared.

[Example 1]
<Manufacture of composite sheet for forming protective film>

(Manufacture of support sheet)
As a base material, a three-layer transparent film (thickness: 80 μm, Young's modulus 50 MPa at 23 ° C., matte surface / gloss surface base material) made of a mixed resin of polypropylene (PP) and an olefinic thermoplastic elastomer (TPO) On the surface, the pressure-sensitive adhesive composition (I-4-1) obtained above was applied and dried by heating at 100 ° C. for 2 minutes, so that a non-energy having a thickness of 5 μm was formed on one surface of the substrate. A transparent support sheet (10) -1 having a linear curable pressure-sensitive adhesive layer was obtained. By applying the adhesive composition to the mat surface, the mat surface was embedded, light scattering was reduced, and transparency was improved.

(Manufacture of composite sheet for protective film formation)
A protective film-forming composition (III) obtained above was applied to the release-treated surface of a release film (“SP-PET 381031” manufactured by Lintec Co., Ltd., thickness 38 μm) obtained by releasing one side of a polyethylene terephthalate film by silicone treatment. -1) was coated with a die coater and dried at 100 ° C. for 2 minutes to prepare a thermosetting protective film-forming film (13) -1 having a thickness of 25 μm.

Next, the release film is removed from the pressure-sensitive adhesive layer of the support sheet (10) -1 obtained above, and the thermosetting protective film-forming film (13) obtained above is formed on the exposed surface of the pressure-sensitive adhesive layer. Example 1 in which the exposed surface of 1 was laminated, and the base material, the pressure-sensitive adhesive layer, the thermosetting protective film-forming film (13) -1 and the release film were laminated in this order in the thickness direction. A composite sheet for forming a protective film was produced.

(Measurement of thickness)
The measurement was performed using a constant pressure thickness measuring device (product name “PG-02” manufactured by Teclock Co., Ltd.).

<Elastic modulus measurement test of adhesive layer>
The pressure-sensitive adhesive composition (I-4-1) is applied to the release surface of the release sheet to form a pressure-sensitive adhesive layer, and then pressure-bonded to the pressure-sensitive adhesive layer that exposes the release surface of the separately prepared release sheet. A pressure-sensitive adhesive sheet comprising a sheet / pressure-sensitive adhesive layer / release sheet was prepared. The release sheet was peeled off from the pressure-sensitive adhesive sheet, and a plurality of pressure-sensitive adhesive layers were laminated to a thickness of 200 μm. A 30 mm × 4 mm rectangle (thickness: 200 μm) was punched out from the resulting laminate of the pressure-sensitive adhesive layer, and this was used as a measurement sample.

By using a dynamic viscoelasticity measuring apparatus (trade name “Rheobibron DDV-II-EP1” manufactured by Orientec Co., Ltd.), measurement mode: tensile mode, frequency: 11 Hz, measurement temperature range: −20 to 150 ° C., heating rate: The storage elastic modulus was measured under the condition of 3 ° C./min, and the values at 23 ° C. and 70 ° C. were read.

<Measurement test of adhesive force (before curing) between protective film-forming film and adhesive layer>
After preparing the protective film-forming composite sheet and curing at 23 ° C. for 1 week, the adhesive strength between the protective film-forming film and the support sheet (adhesive layer) of this test piece is as follows. It measured by the method of.
The release film of the protective film-forming composite sheet cut to a width of 25 mm and a length of 250 mm was removed, and the exposed surface was attached to the mirror wafer by reciprocating once with a 2 kg roller so that the protective film-forming layer was in contact with the mirror wafer surface. . After standing at 23 ° C. and 50% RH for 20 minutes, peeling is performed at a peeling speed of 300 mm / min so that the angle is 180 ° between the protective film-forming film and the adhesive layer of the support sheet. did. This peeling force (mN / 25 mm) was defined as the adhesive force (before curing) between the protective film-forming film and the adhesive layer.

<Cool expand test and test of occurrence of floating marks>
The protective film forming layer surface of the composite sheet for protective film formation is attached to the ground surface of a silicon wafer (diameter: 8 inches, thickness: 150 μm, ground surface: # 2000) with a back-ground tape that has been ground on the back. Attached while heating to 70 ° C. using ADWILL RAD-2700). After the back grind tape is peeled off, the silicon wafer is irradiated with a laser beam having a wavelength of 1342 nm from the ground surface side using a laser saw (DFF 7361, manufactured by DISCO Corporation), and the chip size is 7 mm × inside the silicon wafer. The modified layer was formed to be 7 mm. Next, using an expander (DDS2300, manufactured by DISCO Corporation), the silicon wafer is individually expanded into 7 mm × 7 mm chips by performing cool expansion at a pushing height: 20 mm, a pushing speed: 20 mm / s, and a temperature: −15 ° C. While being cut into pieces, the thermosetting protective film-forming film was cleaved. The jig (sub ring) was attached to the support sheet to maintain the expanded state, and an adhesive sheet was attached to the side opposite to the support sheet (that is, the chip side).

Thereafter, the chip was peeled off from the support sheet, and the floating marks were observed. By the adhesive sheet sticking operation, even if the support sheet is peeled off, the separated chips can be observed without being separated. By observing with the digital microscope from the grinding surface side of the silicon chip, the color of the outer peripheral part of the silicon chip changes if there is any floating (peeling) between the adhesive layer and the thermosetting protective film forming film. Thus, the presence or absence of a floating mark before curing was evaluated.

No lifting: No lifting (peeling) between the pressure-sensitive adhesive layer and the thermosetting protective film-forming film is observed.
There was lifting: lifting (peeling) was observed between the pressure-sensitive adhesive layer and the thermosetting protective film-forming film.

<Cool expanding test and test for disappearance of floating marks>
Similarly, a modified layer is formed with a laser so that the chip size is 7 mm × 7 mm inside a back-ground ground silicon wafer with a back-ground tape that has been ground back, and a protective film is formed on the ground surface of the silicon wafer. The protective film-forming layer surface of the composite sheet was attached while heating to 70 ° C. By using an expander (Disco 2300, manufactured by Disco Corporation), the height is 20 mm, the speed is 20 mm / s, the temperature is −15 ° C., and the chip is singulated into 7 mm × 7 mm chips and thermosetting protected. The film forming film was cleaved. The jig (sub ring) was attached to the support sheet to maintain the expanded state, and an adhesive sheet was attached to the side opposite to the support sheet (that is, the chip side). Thereafter, heat curing was performed under conditions of 130 ° C. for 2 hours, and the thermosetting protective film-forming film was used as a protective film.

After that, when the support sheet is peeled off and observed with a digital microscope from the grinding surface side of the silicon chip, the color of the outer peripheral part of the silicon chip is the one that has floated (peeled) between the adhesive layer and the protective layer. It changed, and this evaluated the presence or absence of the float after hardening.
No lifting: No lifting (peeling) between the pressure-sensitive adhesive layer and the protective layer is observed.
Floating occurred: Floating (peeling) was observed between the pressure-sensitive adhesive layer and the protective layer.

<Pickup test>
Laser light with a wavelength of 1342 nm is applied to a silicon wafer with a back-grinded tape with a ground surface (diameter: 6 inches, thickness: 150 μm, ground surface: # 2000) using a laser saw (DFF 7361, manufactured by Disco Corporation). Was irradiated from the grinding surface side to form a modified layer having a size of 5 mm × 5 mm in the silicon wafer. Using a tape mounter (ADWILL RAD-2700, manufactured by Lintec Corporation), the surface of the protective film-forming film of the protective film-forming composite sheet was attached to the ground surface of the silicon wafer while heating to 70 ° C. Using an expander (Disco 2300, manufactured by Disco Corporation), the expanded state is 20 mm / s, the pushing speed is 20 mm / s, and the temperature is −15 ° C. Fixed. As a result, the film was divided into 5 mm × 5 mm chips and the protective film-forming film was cleaved.

After that, heat curing was performed under conditions of 130 ° C. for 2 hours, and No. 5 needle (number of pins: 1 pin, “JISS 3008 hand-sewn needle”) was used as a push-up gauge (“MODEL-RE” manufactured by Aiko Engineering Co., Ltd.). The semiconductor chip with a protective film was pushed up over the support sheet with a push-up amount of 3.0 mm and a push-up speed of 1 mm / s. The needle was pushed up from the support sheet side, and the chip breakage / peeling of the protective layer from the chip was visually evaluated according to the following criteria.

◯: Of the 10 chips tested, no chip chipping or peeling of the protective layer from the chip is observed.
X: Of the 10 chips tested, chip breakage / peeling of the protective layer from the chips occurred for at least one chip.

The measurement result of the storage elastic modulus (G ′ (70)) at 70 ° C. and the storage elastic modulus (G ′ (23)) at 23 ° C. of the pressure-sensitive adhesive layer of the composite sheet for protective film formation of Example 1 is shown. The results are shown in Table 1. In the protective film-forming composite sheet of Example 1, the adhesive layer and the thermosetting material were observed near the boundary where the semiconductor chip was cleaved, as shown in the microscopic image of FIG. There was floating between the protective film-forming film. However, as shown in FIG. 4 (b), the float disappeared under the subsequent 130 ° C. thermosetting conditions. Moreover, the semiconductor chip with a protective film could be picked up satisfactorily. It was shown in Table 1 with the measurement result of the adhesive force (before hardening) between the film for protective film formation and an adhesive layer.

[Comparative Example 1]
<Manufacture and evaluation of protective film-forming composite sheet>
The protective film of Comparative Example 1 was the same as Example 1 except that the pressure-sensitive adhesive composition (I-4-1) used in Example 1 was changed to the pressure-sensitive adhesive composition (I-4-2). A forming composite sheet was prepared.

The storage elastic modulus (G ′ (70)) at 70 ° C., the storage elastic modulus (G ′ (23)) at 23 ° C., and the test of the occurrence of floating marks of the pressure-sensitive adhesive layer of the composite sheet for forming a protective film of Comparative Example 1 Table 1 shows the measurement results of the test for disappearance of the floating marks, the pickup test, and the adhesive strength (before curing) between the protective film-forming film and the adhesive layer.

[Comparative Example 2]
<Manufacture and evaluation of protective film-forming composite sheet>
The protective film of Comparative Example 1 was the same as Example 1 except that the pressure-sensitive adhesive composition (I-4-1) used in Example 1 was changed to the pressure-sensitive adhesive composition (I-4-3). A forming composite sheet was prepared.

Storage adhesive modulus at 70 ° C. (G ′ (70)), storage elastic modulus at 23 ° C. (G ′ (23)) of the adhesive layer of the protective film-forming composite sheet of Comparative Example 2 Table 1 shows the measurement results of the test for disappearance of the floating marks, the pickup test, and the adhesive strength (before curing) between the protective film-forming film and the adhesive layer.

As apparent from the results in Table 1, in the production of the semiconductor chip using the protective film-forming composite sheet of Example 1, the storage elastic modulus (G ′ (70)) at 70 ° C. of the pressure-sensitive adhesive layer was 0.00. It is 16MPa or less, and the storage elastic modulus (G '(23)) in 23 degreeC is 0.10MPa or more, Between the adhesive layer produced after a cool expansion, and the film for thermosetting protective film formation Can be eliminated by lowering the modulus of elasticity of the pressure-sensitive adhesive layer under the subsequent heat curing conditions of 130 ° C., so that no floating marks can be left, and a semiconductor chip with a protective film can be well picked up. did it.
In the manufacture of a semiconductor chip using the composite sheet for forming a protective film of Comparative Example 1, the storage modulus (G ′ (70)) at 70 ° C. of the pressure-sensitive adhesive layer is 0.16 MPa or less, but the storage at 23 ° C. Since the elastic modulus (G ′ (23)) is smaller than 0.10 MPa, the float between the pressure-sensitive adhesive layer and the thermosetting protective film-forming film disappears under the 70 ° C. application condition after the cool expansion. However, since the semiconductor chip with a protective film was too close to the adhesive layer, it could not be picked up well.
The protective sheet-forming composite sheet of Comparative Example 2 is a composite sheet having a general composition used in a method of dividing a semiconductor wafer together with a protective film using a dicing blade. In the manufacture of a semiconductor chip using the composite sheet for forming a protective film of Comparative Example 2, the storage elastic modulus (G ′ (23)) at 23 ° C. of the pressure-sensitive adhesive layer is 0.10 MPa or more, but storage at 70 ° C. Since the elastic modulus (G ′ (70)) is larger than 0.16 MPa, the float between the pressure-sensitive adhesive layer and the thermosetting protective film-forming film generated after the cool expansion is then thermosetting at 130 ° C. Even under the conditions of the above, it did not disappear, and the float remained.

The composite sheet for forming a protective film of the present invention can be suitably used for the production of a semiconductor chip with a protective film to which a dividing method using cool expand is applied.

DESCRIPTION OF SYMBOLS 1, 2 ... Composite sheet for protective film formation, 10 ... Support sheet, 10a ... Surface of support sheet, 11 ... Base material, 11a ... Surface of base material, 12 ... Adhesion Agent layer, 12a... Surface of adhesive layer, 13, 23... Film for forming thermosetting protective film, 13a, 23a... Surface of film for forming thermosetting protective film, 13 ', 23' ... Protective film, 15 ... Release film, 15a ... Surface of release film, 16 ... Adhesive layer for jig, 17 ... Ring frame, 18 ... Semiconductor wafer (silicon wafer) , 18a ... back surface of semiconductor wafer, 18c ... modified layer, 19 ... semiconductor chip, 20 ... back grind tape, SD ... laser light irradiation, CE ... cool expanding

Claims (6)

1. A substrate, a pressure-sensitive adhesive layer, and a thermosetting protective film-forming film are provided in this order,
   A protective film having a storage elastic modulus (G ′ (70)) at 70 ° C. of 0.16 MPa or less and a storage elastic modulus (G ′ (23)) at 23 ° C. of 0.10 MPa or more of the pressure-sensitive adhesive layer. Composite sheet for forming.
2. The composite sheet for forming a protective film according to claim 1, wherein the pressure-sensitive adhesive layer has a storage elastic modulus (G '(70)) at 70 ° C of 0.01 MPa or more.
3. The composite sheet for forming a protective film according to claim 1 or 2, wherein the pressure-sensitive adhesive layer has a storage elastic modulus (G '(23)) at 23 ° C of 0.45 MPa or less.
4. The composite sheet for forming a protective film according to claim 3, wherein the pressure-sensitive adhesive layer is non-energy ray curable or energy ray curable.
5. The composite sheet for forming a protective film according to claim 3 or 4, wherein the pressure-sensitive adhesive layer has a thickness of 3 to 20 µm.
6. A step of laminating a semiconductor wafer on the thermosetting protective film forming film side of the protective film forming composite sheet according to any one of claims 1 to 5 to form a laminate;
   Irradiating a semiconductor wafer with laser light to form a modified layer inside the semiconductor wafer; and
   Cool expanding the laminate at a temperature lower than room temperature, and dividing the semiconductor wafer and the thermosetting protective film forming film,
   A process for producing a semiconductor chip with a protective film, comprising: heating and curing the thermosetting protective film-forming film of the laminate to form a protective film.

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