KR20210027118A - Composite sheet for forming protective film - Google Patents

Abstract

Provided is a composite sheet for forming a protective film, which is provided with a base material, and in which an energy ray-curable adhesive layer and a film for forming the protective film are laminated in this order and in contact with each other on one surface of the base material. Moreover, the composite sheet for forming the protective film has gel fraction of the adhesive layer of 80% or more or gel fraction of the adhesive layer of 20% or more and less than 80%, and has glass transition temperature of the film for forming the protective film of 3°C or more.

Description

Composite sheet for forming a protective film {COMPOSITE SHEET FOR FORMING PROTECTIVE FILM}

The present invention relates to a composite sheet for forming a protective film. This application claims priority based on Japanese Patent Application No. 2019-158473 for which it applied to Japan on August 30, 2019, and uses the content here.

In the manufacturing process of a semiconductor device, in order to obtain a target object, a work required to be processed is sometimes protected with a protective film.

For example, in manufacturing a semiconductor device to which a mounting method called a face down method is applied, a semiconductor wafer having electrodes such as bumps on a circuit surface is used as a work, and a semiconductor wafer or a semiconductor chip that is a division thereof In some cases, in order to suppress the occurrence of cracks, the rear surface of the semiconductor wafer or the semiconductor chip on the opposite side of the circuit surface is protected with a protective film. In addition, in the manufacturing process of a semiconductor device, a semiconductor device panel, which will be described later, is used as a work, and in order to suppress the occurrence of warpage or cracks in the panel, certain portions of the panel may be protected with a protective film.

In order to form such a protective film, for example, a composite sheet for forming a protective film comprising a support sheet and a film for forming a protective film for forming a protective film is further provided on one side of the support sheet is used.

The film for protective film formation may function as a protective film by curing thereof, or may function as a protective film in an uncured state. In addition, the support sheet can be used to fix a film for forming a protective film or a work provided with a cured product thereof. For example, when a semiconductor wafer is used as a work, the support sheet can be used as a dicing sheet required when dividing the semiconductor wafer into semiconductor chips. Examples of the supporting sheet include a substrate and a pressure-sensitive adhesive layer formed on one side of the substrate; What consists only of a base material, etc. are mentioned. When the support sheet is provided with the pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer is disposed between the substrate and the protective film-forming film in the protective film-forming composite sheet.

In the case of using the above-described composite sheet for forming a protective film, first, a film for forming a protective film in the composite sheet for forming a protective film is affixed to a target location of the work.

Next, in the state of having such a composite sheet for forming a protective film, processing is performed as necessary to obtain a workpiece. For example, when a semiconductor wafer is used as the work, after the protective film-forming composite sheet is affixed to the back surface of the work by the protective film-forming film therein, the protective film is formed by curing the protective film-forming film at appropriate timings, respectively, Cutting a protective film or protective film, dividing a semiconductor wafer into semiconductor chips (dicing), a film for forming a protective film after cutting, or a semiconductor chip having a protective film on the back surface (a semiconductor chip with a protective film forming film or a protective film formed A semiconductor chip) is picked up from the supporting sheet and the like is appropriately performed. When a semiconductor chip on which a protective film-forming film is formed is picked up, the semiconductor chip on which the protective film-forming film is formed becomes a semiconductor chip with a protective film formed by curing of the protective film-forming film, and finally, a semiconductor chip with a protective film is used. The device is manufactured.

In Patent Document 1, a die in which a film for a flip chip type semiconductor back surface formed of a thermosetting resin component and a thermoplastic resin component having a glass transition temperature of 25°C or more and 200°C or less is laminated on a dicing tape with an adhesive laminated on a substrate. A film for a semiconductor back surface integrated with a sinking tape is disclosed.

Japanese Patent No. 5479991

As such a composite sheet for forming a protective film, a support sheet having a pressure-sensitive adhesive layer cured by irradiation with energy rays such as ultraviolet rays is used, in addition to having a support sheet provided with an adhesive layer cured by heating.

Energy ray-curable adhesive is usually composed of a photopolymerizable resin and a photopolymerization initiator, and the photopolymerizable resin is cured by crosslinking with a photopolymerization initiator by irradiation with energy rays, but the photopolymerizable resin and photopolymerization initiator that are not crosslinked before energy ray curing are adhesives. There is a problem that the layer is transferred to the protective film-forming film, or the components of the protective film-forming film are transferred to the pressure-sensitive adhesive layer. When these components are transferred, the curing of the pressure-sensitive adhesive layer after irradiation with energy rays is insufficient, or crosslinking occurs between the pressure-sensitive adhesive layer and the film for forming a protective film, so that a semiconductor chip with a cured protective film on the back surface (a semiconductor chip with a protective film formed thereon When) is picked up from the support sheet, the semiconductor chip on which the protective film is formed cannot be peeled from the support sheet, and there is a possibility of peeling between the semiconductor chip and the protective film.

The present invention comprises a substrate, an energy ray-curable pressure-sensitive adhesive layer and a protective film-forming film on one side of the substrate are stacked in contact with each other in this order, and when a semiconductor chip on which a protective film is formed is picked up from a support sheet, a semiconductor An object of the present invention is to provide a composite sheet for forming a protective film capable of peeling a semiconductor chip on which a protective film is formed from a support sheet without being peeled off between the chip and the protective film.

The present invention comprises a substrate, an energy ray-curable pressure-sensitive adhesive layer and a protective film-forming film on one side of the substrate are stacked in contact with each other in this order, and the gel fraction of the pressure-sensitive adhesive layer is 80% or more. Provide a sheet.

In the present invention, a substrate is provided, and an energy ray-curable pressure-sensitive adhesive layer and a protective film-forming film are laminated in contact with each other in this order on one side of the substrate, and the gel fraction of the pressure-sensitive adhesive layer is 20% or more and less than 80%. It provides a protective film-forming composite sheet having a glass transition temperature (Tg) of 3° C. or higher of the protective film-forming film.

In the composite sheet for forming a protective film of the present invention, the loss modulus at 23° C. of the film for forming a protective film is preferably 3 MPa or more.

In the composite sheet for forming a protective film of the present invention, the protective film-forming film contains a filler (D), and in the protective film-forming film, the content ratio of the filler (D) to the total mass of the protective film-forming film is 50 It is preferable that it is mass% or more.

According to the present invention, when a substrate is provided, an energy ray-curable pressure-sensitive adhesive layer and a protective film-forming film are stacked in contact with each other in this order on one side of the substrate, and a semiconductor chip with a protective film is picked up from the support sheet. , There is provided a composite sheet for forming a protective film capable of peeling the semiconductor chip on which the protective film is formed from the support sheet without being peeled between the semiconductor chip and the protective film.

1 is a cross-sectional view schematically showing an example of a composite sheet for forming a protective film according to an embodiment of the present invention.
2 is a cross-sectional view schematically showing another example of a composite sheet for forming a protective film according to an embodiment of the present invention.
3A is a cross-sectional view schematically illustrating an example of a method of manufacturing a semiconductor chip with a protective film formed when the composite sheet for forming a protective film according to an embodiment of the present invention is used.
3B is a cross-sectional view schematically illustrating an example of a method of manufacturing a semiconductor chip with a protective film formed when the composite sheet for forming a protective film according to an embodiment of the present invention is used.
3C is a cross-sectional view schematically illustrating an example of a method of manufacturing a semiconductor chip with a protective film formed when the composite sheet for forming a protective film according to an embodiment of the present invention is used.
3D is a cross-sectional view schematically illustrating an example of a method of manufacturing a semiconductor chip with a protective film formed when the composite sheet for forming a protective film according to an embodiment of the present invention is used.
3E is a cross-sectional view schematically illustrating an example of a method of manufacturing a semiconductor chip with a protective film formed when the composite sheet for forming a protective film according to an embodiment of the present invention is used.

◇Composite sheet for forming a protective film

The composite sheet for forming a protective film according to the first embodiment of the present invention includes a substrate, and an energy ray-curable pressure-sensitive adhesive layer and a protective film-forming film are laminated on one side of the substrate in contact with each other in this order, and the pressure-sensitive adhesive The gel fraction of the layer is 80% or more.

By setting the gel fraction of the energy ray-curable pressure-sensitive adhesive of the pressure-sensitive adhesive layer of the protective film-forming composite sheet to the lower limit or more, it is possible to suppress the mutual migration of components between the energy-ray-curable pressure-sensitive adhesive layer and the protective film-forming film before energy-ray curing. When the semiconductor chip on which the protective film is formed is picked up from the support sheet, it becomes possible to peel off the semiconductor chip on which the protective film is formed from the support sheet without being peeled between the semiconductor chip and the protective film.

The composite sheet for forming a protective film according to the second embodiment of the present invention includes a substrate, and an energy ray-curable pressure-sensitive adhesive layer and a protective film-forming film are stacked in contact with each other in this order on one side of the substrate. The gel fraction of the layer is 20% or more and less than 80%, and the glass transition temperature of the protective film-forming film is 3°C or more.

When the glass transition temperature of the protective film-forming film is 3°C or higher, even if the gel fraction of the pressure-sensitive adhesive layer before energy ray curing is 20% or more and less than 80%, between the energy ray-curable adhesive layer and the protective film-forming film before energy ray curing It is possible to suppress the transition of the components to each other, and when the semiconductor chip with the protective film is picked up from the support sheet, it becomes possible to peel the semiconductor chip with the protective film from the support sheet without peeling between the semiconductor chip and the protective film.

In the composite sheet for forming a protective film of the present invention, the loss modulus E" at 23° C. of the film for forming a protective film is preferably 3 MPa or more, more preferably 5 MPa or more, even more preferably 10 MPa or more, for example, It may be any of 17 MPa or more and 45 MPa or more. When the loss elastic modulus at 23° C. of the protective film-forming film is equal to or greater than the lower limit, the energy ray-curable pressure-sensitive adhesive is used for forming a protective film of a low molecular weight component such as a photopolymerizable resin or a photopolymerization initiator. It becomes possible to suppress the migration to the film.

The loss modulus E" at 23°C of the protective film-forming film is preferably 100 MPa or less, and more preferably 90 MPa or less. The loss elastic modulus E" at 23°C of the protective film-forming film is equal to or less than the upper limit. By doing so, the handling property of the affixing to the film work for forming a protective film can be improved.

In the composite sheet for forming a protective film of the present invention, the protective film-forming film contains a filler (D), and in the protective film-forming film, the ratio of the content of the filler (D) to the total mass of the protective film-forming film is It is preferably 50% by mass or more, more preferably 53% by mass or more, still more preferably 55% by mass or more, and may be, for example, 60% by mass. In the protective film-forming film, when the ratio of the content of the filler (D) to the total mass of the protective film-forming film is equal to or greater than the lower limit, a low molecular weight component such as a photopolymerizable resin or a photopolymerization initiator of the energy ray-curable pressure-sensitive adhesive The migration to the film for forming a protective film of can be further suppressed.

In the protective film-forming film, the ratio of the content of the filler (D) to the total mass of the protective film-forming film is preferably 90% by mass or less, and more preferably 80% by mass or less. In the protective film-forming film, when the ratio of the content of the filler (D) to the total mass of the protective film-forming film is equal to or less than the upper limit, the adhesion of the protective film-forming film to the work is improved.

The film for protective film formation in the composite sheet for protective film formation of the present embodiment may be curable or non-curable.

In this specification, even after the film for protective film formation is cured, this laminated structure is referred to as "composite sheet for protective film formation" as long as the laminated structure of the cured product of the support sheet and the protective film-forming film is maintained.

In addition, in this specification, the description simply "adhesive layer" means "the adhesive layer before hardening".

Even if the composite sheet for forming a protective film of the present embodiment is provided with a substrate, a pressure-sensitive adhesive layer, a film for forming a protective film, and another layer that does not correspond to any of the release film within the range that does not impair the effect of the present invention. do.

The type of the other layer is not particularly limited and may be arbitrarily selected according to the purpose.

The arrangement position, shape, size, etc. of the other layers may also be arbitrarily selected according to the type, and is not particularly limited, but the size of the protective film-forming film is preferably larger than that of the work.

The thickness of the workpiece to be affixed to the composite sheet for forming a protective film of the present embodiment is not particularly limited, but it is preferably 30 to 1000 μm in view of easier processing (eg, division) of the workpiece to be described later. And more preferably 70 to 400 µm.

Although the composite sheet for forming a protective film of the present embodiment is for affixing to a work, a semiconductor wafer is mentioned as a preferable example of a work to be affixed. It is preferable that the said composite sheet for forming a protective film is for sticking to the back surface of a semiconductor wafer.

1 is a cross-sectional view schematically showing an example of a composite sheet for forming a protective film according to an embodiment of the present invention.

The protective film-forming composite sheet 101 shown here is a protective film formed on the support sheet 10 and one side of the support sheet 10 (in this specification, it may be referred to as a ``first surface'') 10a It is comprised with the film 13 for formation.

The support sheet 10 is configured with a substrate 11 and a pressure-sensitive adhesive layer 12 formed on one side 11a of the substrate 11. Among the composite sheet 101 for forming a protective film, the pressure-sensitive adhesive layer 12 is disposed between the substrate 11 and the film 13 for forming a protective film.

That is, the protective film-forming composite sheet 101 is constituted by laminating the base material 11, the pressure-sensitive adhesive layer 12, and the protective film-forming film 13 in this order in their thickness direction.

The surface of the supporting sheet 10 on the side of the film 13 for forming a protective film (in this specification, it may be referred to as a ``first surface'') 10a is different from the side of the substrate 11 of the pressure-sensitive adhesive layer 12 It is the same as 12a on the opposite side (in this specification, it may be referred to as "the first surface").

The composite sheet 101 for forming a protective film further includes an adhesive layer 16 for a jig and a release film 15 on the film 13 for forming a protective film.

In the composite sheet 101 for forming a protective film, a protective film-forming film 13 is laminated on the entire surface or almost the entire surface of the first surface 12a of the pressure-sensitive adhesive layer 12, and the pressure-sensitive adhesive of the protective film-forming film 13 A jig adhesive layer 16 is laminated on a part of 13a on the side opposite to the side of the layer 12 (in this specification, it may be referred to as a "first surface"), that is, a region near the periphery. In addition, of the first surface 13a of the protective film forming film 13, the region in which the jig adhesive layer 16 is not laminated and the protective film forming film 13 side of the jig adhesive layer 16 The release film 15 is laminated on the opposite side surface (in this specification, it may be referred to as a "first surface") 16a.

It is not limited to the case of the composite sheet 101 for protective film formation, In the composite sheet for protective film formation of this embodiment, the release film (for example, the release film 15 shown in FIG. 1) is an arbitrary structure, and this The composite sheet for forming a protective film of the embodiment may or may not be equipped with a release film.

The jig adhesive layer 16 is used to fix the protective film-forming composite sheet 101 to a jig such as a ring frame.

The jig adhesive layer 16 may have, for example, a single-layer structure containing an adhesive component, or may have a multilayer structure in which layers containing an adhesive component are laminated on both surfaces of a sheet serving as a core material.

In the protective film-forming composite sheet 101, a part of the work (not shown) is affixed to the first surface 13a of the protective film-forming film 13 with the release film 15 removed, and additionally for a jig. The first surface 16a of the adhesive layer 16 is used by being affixed to a jig such as a ring frame.

2 is a cross-sectional view schematically showing another example of a composite sheet for forming a protective film according to an embodiment of the present invention.

On the other hand, in the drawings after FIG. 2, the same components as those shown in the previously described drawings are denoted by the same reference numerals as those in the illustrated drawings, and detailed descriptions thereof will be omitted.

The protective film-forming composite sheet 102 shown here has a different shape and size of the protective film-forming film, and the jig adhesive layer is laminated on the first side of the pressure-sensitive adhesive layer rather than the first side of the protective film-forming film. Other than that, it is the same as the composite sheet 101 for forming a protective film shown in FIG. 1.

More specifically, in the protective film-forming composite sheet 102, the protective film-forming film 23 is a partial region of the first surface 12a of the pressure-sensitive adhesive layer 12, that is, the width of the pressure-sensitive adhesive layer 12 It is laminated in a region on the center side in the direction (left and right directions in Fig. 2). Further, of the first surface 12a of the pressure-sensitive adhesive layer 12, the jig adhesive layer 16 is laminated in a region in which the protective film-forming film 23 is not laminated, that is, a region in the vicinity of the periphery. In addition, the surface of the protective film-forming film 23 on the side opposite to the pressure-sensitive adhesive layer 12 side (in this specification, it may be referred to as the ``first surface'') 23a and the adhesive layer 16 for a jig. A release film 15 is laminated on one side 16a.

Up to this point, for the composite sheet for forming a protective film having a jig adhesive layer, the composite sheet 101 for forming a protective film shown in Fig. 1 and the composite sheet 102 for forming a protective film shown in Fig. 2 have been shown. It is an example of another composite sheet for forming a protective film with a layer.

In such a composite sheet for forming a protective film having a jig adhesive layer, the first surface of the jig adhesive layer is affixed to a jig such as a ring frame, and is used.

As described above, the composite sheet for forming a protective film according to the present embodiment may be provided with an adhesive layer for a jig in any form of the supporting sheet and the film for forming a protective film.

Examples of the composite sheet for forming a protective film that does not have a jig adhesive layer include those that do not have the jig adhesive layer 16 in the protective film-forming composite sheet 102 shown in FIG. 2. I can. However, this is an example of another composite sheet for forming a protective film that does not have a jig adhesive layer.

1 and 2, as constituting the composite sheet for forming a protective film, a substrate, an adhesive layer, a film for forming a protective film, and a release film are shown, but the composite sheet for forming a protective film of the present embodiment corresponds to any of these. You may have provided the said other layer which does not do.

When the composite sheet for forming a protective film shown in FIGS. 1 and 2 is provided with the other layer, the arrangement position thereof is not particularly limited except between the pressure-sensitive adhesive layer and the film for forming a protective film.

In the composite sheet for forming a protective film of the present embodiment, the size and shape of each layer can be arbitrarily selected according to the purpose.

Hereinafter, the configuration of the composite sheet for forming a protective film will be described in detail.

◇Support sheet

The support sheet according to an embodiment of the present invention can be laminated with a protective film-forming film, as described later, to constitute a protective film-forming composite sheet.

The support sheet of the present embodiment can be used to fix the film for forming a protective film to be described later or a work provided with the cured product at any location.

Examples of the work include semiconductor wafers and semiconductor device panels. The semiconductor device panel is handled in the manufacturing process of a semiconductor device, and a specific example thereof is a one formed by mounting a plurality of electronic components on a single circuit board.

In this specification, what processed a work is referred to as a "work-processed object". For example, when a work is a semiconductor wafer, a semiconductor chip is mentioned as a work processed object.

For example, when the work is a semiconductor wafer, the support sheet of the present embodiment can be used to fix a semiconductor wafer provided with a protective film forming film or a cured product thereof on the back surface.

Examples of the supporting sheet include a substrate and a pressure-sensitive adhesive layer formed on one side of the substrate. When the support sheet includes an adhesive layer, the adhesive layer is disposed between the substrate and the film for forming a protective film in the composite sheet for forming a protective film to be described later.

When a support sheet provided with a base material and a pressure-sensitive adhesive layer is used, in the composite sheet for forming a protective film, the adhesive force or adhesion between the support sheet and the film for forming a protective film can be easily adjusted.

When a supporting sheet composed of only a base material is used, a composite sheet for forming a protective film can be manufactured at low cost.

When a supporting sheet provided with a base material and an adhesive layer is used, a new function can be imparted to the supporting sheet or the composite sheet for forming a protective film. In addition, the adhesive force or adhesion between the support sheet and the protective film-forming film can be more easily adjusted than in the case of the pressure-sensitive adhesive layer described above.

◎ Description

The substrate is in the form of a sheet or a film, and examples of the material constituting the substrate include various resins.

Examples of the resin include polyolefins such as low-density polyethylene (LDPE) and polypropylene (PP); Ethylene-methacrylic acid copolymer (EMAA); Polyvinyl chloride (PVC); Polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT); Polyethersulfone, polyacrylic acid ester; And polycarbonate (PC).

The number of resins constituting the substrate may be only one type, or may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

The substrate may be composed of one layer (single layer), may be composed of a plurality of layers of two or more layers, and when composed of a plurality of layers, the plurality of layers may be the same or different from each other, and the combination of the plurality of layers is not particularly limited. Does not.

In the present specification, it is not limited to the case of the description, and "a plurality of layers may be the same or different from each other" means that "all the layers may be the same, all layers may be different, and only some of the layers may be the same." It means, and "a plurality of layers are different from each other" means that "at least one of the constituent materials and thicknesses of each layer is different from each other".

The thickness of the substrate is preferably 50 to 300 µm, more preferably 60 to 140 µm, and particularly preferably 80 to 100 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 adhesion to a work or a work-processed product are further improved.

Here, the "thickness of a base material" means the thickness of the entire base material, and, for example, the thickness of a base material comprising a plurality of layers means the total thickness of all layers constituting the base material.

It is preferable that the substrate has high accuracy in thickness, that is, the variation in thickness is suppressed irrespective of the portion. Among the above-described constituent materials, examples of materials that can be used for constituting a substrate having such a high accuracy in thickness include polyolefin, polyethylene terephthalate, and the like.

The substrate may contain various known additives such as fillers, colorants, antistatic agents, antioxidants, organic lubricants, catalysts, and softeners (plasticizers) in addition to the main constituent materials such as the resin.

The substrate may be transparent or opaque, may be colored to the extent that the energy ray curability of the pressure-sensitive adhesive layer is ensured, or another layer may be deposited.

For example, when the film for forming a protective film has energy ray curing properties, it is preferable that the substrate transmits energy rays.

For example, in order to optically inspect the film for protective film formation in the composite sheet for protective film formation through the substrate, it is preferable that the substrate is transparent.

In order to improve the adhesion of the layer formed thereon (for example, a pressure-sensitive adhesive layer, a film for forming a protective film, etc.), the substrate may be subjected to uneven treatment by sand blasting or solvent treatment; Corona discharge treatment, electron beam irradiation treatment, plasma treatment, ozone/ultraviolet irradiation treatment, flame treatment, chromic acid treatment, and oxidation treatment such as hot air treatment may be applied to the surface. In addition, the surface of the substrate may be subjected to a primer treatment.

In addition, the base material is an antistatic coat layer; When the composite sheet for forming a protective film is superimposed and stored, the base material may have a layer that adheres to another sheet or prevents the base material from adhering to the adsorption table.

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

◎Adhesive layer

The pressure-sensitive adhesive layer is in the form of a sheet or a film and contains a pressure-sensitive adhesive.

Examples of the adhesive include adhesive resins such as acrylic resin, urethane resin, rubber resin, silicone resin, epoxy resin, polyvinyl ether, polycarbonate, ester resin, and acrylic resin.

On the other hand, in the present specification, the "adhesive resin" includes both a resin having adhesiveness and a resin having adhesiveness. For example, the adhesive resin includes not only the resin itself but also a resin that exhibits adhesiveness when used in combination with other components such as additives, or a resin that exhibits adhesiveness by the presence of a trigger such as heat or water. .

The pressure-sensitive adhesive layer may consist of one layer (single layer), may consist of a plurality of layers of two or more layers, and in the case of a plurality of layers, the plurality of layers may be the same or different from each other, and the combination of the plurality of layers is specifically limited. It doesn't work.

The thickness of the pressure-sensitive adhesive layer is preferably 1 to 14 µm, more preferably 2 to 12 µm, and may be, for example, 3 to 8 µm. When the thickness of the pressure-sensitive adhesive layer is more than the above lower limit, the effect of forming the pressure-sensitive adhesive layer is more remarkably obtained. When the thickness of the pressure-sensitive adhesive layer is less than or equal to the above upper limit, printing can be performed more favorably on the film for forming a protective film or a cured product thereof in the composite sheet for forming a protective film. Then, this printing can be better visually recognized from the outside on the support sheet side of the composite sheet for forming a protective film and beyond the support sheet.

Here, the "thickness of the adhesive layer" means the thickness of the entire pressure-sensitive adhesive layer, and for example, the thickness of the pressure-sensitive adhesive layer composed of a plurality of layers means the total thickness of all the layers constituting the pressure-sensitive adhesive layer.

In this embodiment, the pressure-sensitive adhesive layer is formed using an energy ray-curable pressure-sensitive adhesive. That is, the pressure-sensitive adhesive layer is energy ray-curable. The energy ray-curable pressure-sensitive adhesive layer can easily adjust physical properties before and after curing. For example, these semiconductor chips can be picked up more easily by curing the energy ray-curable pressure-sensitive adhesive layer before pickup of a semiconductor chip with a protective film formed thereon or a semiconductor chip with a protective film forming film described later.

In the present specification, the term "energy rays" means having both energy among electromagnetic waves or charged particle rays, and examples thereof include ultraviolet rays, radiation, and electron rays. Ultraviolet rays can be irradiated by using, for example, a high-pressure mercury lamp, a fusion lamp, a xenon lamp, a black light, or an LED lamp as an ultraviolet source. The electron beam can be irradiated with what is generated by an electron beam accelerator or the like.

In addition, in this specification, "energy ray hardenability" means a property which hardens|cures by irradiation of energy rays, and "non-energy ray hardenability" means a property which does not harden even if it is irradiated with energy rays.

In the composite sheet for forming a protective film of the first embodiment, the gel fraction of the pressure-sensitive adhesive layer is 80% or more, preferably 85% or more, and more preferably 90% or more. When the gel fraction of the pressure-sensitive adhesive layer is 80% or more, it is possible to suppress the mutual migration of components between the energy-ray-curable pressure-sensitive adhesive layer and the protective film-forming film before energy-ray curing, and the semiconductor chip on which the protective film is formed can be picked up from the support sheet. At this time, it becomes possible to peel off the semiconductor chip on which the protective film is formed from the support sheet without being peeled off between the semiconductor chip and the protective film.

In the composite sheet for forming a protective film of the second embodiment, the gel fraction of the pressure-sensitive adhesive layer is 20% or more and less than 80%, preferably 30% or more and less than 80%, and more preferably 40% or more and less than 80%. Even if the gel fraction of the pressure-sensitive adhesive layer is less than 80%, since the glass transition temperature (Tg) of the film for forming a protective film described below is 3°C or higher, components are mutually transferred between the energy-ray-curable pressure-sensitive adhesive layer and the protective film-forming film before energy-ray curing. When the semiconductor chip with the protective film is picked up from the support sheet, the semiconductor chip with the protective film is not peeled between the semiconductor chip and the protective film, and the semiconductor chip with the protective film can be peeled from the support sheet.

In the composite sheet for forming a protective film of the second embodiment, if the gel fraction of the pressure-sensitive adhesive layer is within the above range, the pressure-sensitive adhesive layer can be easily formed. If the gel fraction is less than 20%, the pressure-sensitive adhesive layer remains in the protective film-forming film and the reliability of the semiconductor chip on which the protective film is formed decreases.

The gel fraction of the pressure-sensitive adhesive layer can be measured by a known method. Specifically, it can be measured by the following method.

A release film in which a release agent layer of a silicone resin is formed on one side of a base film made of polyethylene terephthalate (thickness 38 µm) is prepared. Next, the pressure-sensitive adhesive composition is applied to the peeling-treated surface of this release film and dried to form a pressure-sensitive adhesive layer having a thickness of 20 μm.

Subsequently, this pressure-sensitive adhesive layer is cut into a size of 50 mm×100 mm to form a sample, and wrapped with a 100 mm×150 mm nylon mesh sheet (mesh size 200) to form a test piece. The mass M1 of only the sample was weighed with a precision balance, and then the test piece was immersed in ethyl acetate (100 mL) at 25° C. for 24 hours, and then the test piece was taken out and dried at 120° C. for 1 hour, and further 23° C., relative humidity. It is left to stand for 1 hour under 50% conditions, and humidity control is performed. Next, the mass M2 of only the sample excluding the mass of the mesh sheet of the test piece is measured with a precision balance. Then, the gel fraction of the sample (that is, the pressure-sensitive adhesive layer) before energy ray irradiation is calculated by the following equation.

Gel fraction of the pressure-sensitive adhesive layer (%) = (M2/M1) × 100

<<adhesive composition>>

The pressure-sensitive adhesive layer can be formed using a pressure-sensitive adhesive composition containing a pressure-sensitive adhesive. For example, by coating the pressure-sensitive adhesive composition on the surface to be formed of the pressure-sensitive adhesive layer and drying as necessary, the pressure-sensitive adhesive layer can be formed on a target site. The content ratio of components that do not vaporize at room temperature in the pressure-sensitive adhesive composition is usually the same as the content ratio of the components in the pressure-sensitive adhesive layer. In the present specification, "room temperature" means a temperature that is not particularly cold or heated, that is, an ordinary temperature, and examples thereof include a temperature of 15 to 25°C.

Coating of the pressure-sensitive adhesive composition may be performed by a known method, for example, an air knife coater, a blade coater, a bar coater, a gravure coater, a roll coater, a roll knife coater, a curtain coater, a die coater, a knife coater, a screen coater, a Mayer bar. The method of using various coaters, such as a coater and a kiss coater, is mentioned.

Drying conditions of the pressure-sensitive adhesive composition are not particularly limited. When the adhesive composition contains a solvent mentioned later, it is preferable to heat-dry. It is preferable to dry the pressure-sensitive adhesive composition containing a solvent under the conditions of 10 seconds to 5 minutes at 70-130 degreeC, for example.

In the case of forming the pressure-sensitive adhesive layer on the substrate, for example, the pressure-sensitive adhesive layer may be laminated on the substrate by coating the pressure-sensitive adhesive composition on the substrate and drying as necessary. In the case of forming the pressure-sensitive adhesive layer on the substrate, for example, by coating the pressure-sensitive adhesive composition on the release film and drying it as necessary, a pressure-sensitive adhesive layer is formed on the release film, and the exposed surface of the pressure-sensitive adhesive layer is used as the substrate. By bonding with one surface of, an adhesive layer may be laminated on the substrate. In this case, the release film may be removed at any timing in the process of manufacturing or using the composite sheet for forming a protective film.

In the present invention, the pressure-sensitive adhesive is energy ray-curable. As an energy ray-curable adhesive composition, for example, a non-energy ray-curable adhesive resin (I-1a) (hereinafter sometimes abbreviated as ``adhesive resin (I-1a)'') and an energy ray-curable compound are contained. Pressure-sensitive adhesive composition (I-1); A pressure-sensitive adhesive composition containing an energy ray-curable pressure-sensitive adhesive resin (I-2a) in which an unsaturated group is introduced into the side chain of the pressure-sensitive adhesive resin (I-1a) (hereinafter sometimes abbreviated as ``adhesive resin (I-2a)'') ( I-2); The adhesive composition (I-3) containing the said adhesive resin (I-2a) and an energy ray-curable compound, etc. are mentioned.

[Adhesive resin (I-1a)]

The pressure-sensitive adhesive composition (I-1), the pressure-sensitive adhesive composition (I-2) and the pressure-sensitive adhesive composition (I-3) (hereinafter, these pressure-sensitive adhesive compositions are encompassed, and are referred to as ``adhesive compositions (I-1) to (I-3)''). It is preferable that the said adhesive resin (I-1a) in abbreviated) is an acrylic resin.

Examples of the acrylic resin include an acrylic polymer having at least a structural unit derived from an alkyl (meth)acrylate.

Examples of the (meth)acrylate alkyl ester include those having 1 to 20 carbon atoms in the alkyl group constituting the alkyl ester, and the alkyl group is preferably linear or branched.

In addition, in this specification, "(meth)acrylic acid" is a concept including both "acrylic acid" and "methacrylic acid". The same applies to terms similar to (meth)acrylic acid, for example, "(meth)acryloyl group" is a concept including both "acryloyl group" and "methacryloyl group", and "(meth) "Acrylate" is a concept including both "acrylate" and "methacrylate".

It is preferable that the said acrylic polymer further has a structural unit derived from a functional group-containing monomer in addition to the structural unit derived from the (meth)acrylate alkyl ester.

As the functional group-containing monomer, for example, the functional group becomes a starting point for crosslinking by reacting with a crosslinking agent described later, or the functional group reacts with an unsaturated group in an unsaturated group-containing compound described later, thereby introducing an unsaturated group into the side chain of the acrylic polymer. What makes it possible is mentioned.

Examples of the functional group-containing monomer include a hydroxyl group-containing monomer, a carboxyl group-containing monomer, an amino group-containing monomer, and an epoxy group-containing monomer.

In addition to the structural unit derived from the (meth)acrylate 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 an alkyl (meth)acrylate or the like.

Examples of the other monomers include styrene, α-methylstyrene, vinyltoluene, vinyl formate, vinyl acetate, acrylonitrile, and acrylamide.

In the pressure-sensitive adhesive compositions (I-1) to (I-3), the constituent units of the acrylic resin, such as the acrylic polymer, may be only one type, or may be two or more types, and in the case of two or more types, combinations and ratios thereof are optionally You can choose.

In the acrylic polymer, the content of the structural unit derived from the functional group-containing monomer is preferably 1 to 35 mass with respect to the total amount of the structural unit.

As for the adhesive resin (I-1a) contained in the adhesive composition (I-1), only one type may be used, or two or more types may be used, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

In the adhesive composition (I-1), the content ratio of the adhesive resin (I-1a) to the total mass of the adhesive composition (I-1) is preferably 5 to 99% by mass.

[Adhesive resin (I-2a)]

The pressure-sensitive adhesive resin (I-2a) in the pressure-sensitive adhesive compositions (I-2) and (I-3) contains, for example, an unsaturated group having an energy ray-polymerizable unsaturated group in the functional group in the pressure-sensitive adhesive resin (I-1a). It is obtained by reacting a compound.

The unsaturated group-containing compound is a compound having a group capable of bonding to the adhesive resin (I-1a) by reacting with a functional group in the adhesive resin (I-1a) in addition to the energy ray polymerizable unsaturated group.

Examples of the energy ray-polymerizable unsaturated group include a (meth)acryloyl group, a vinyl group (ethenyl group), and an allyl group (2-propenyl group), and a (meth)acryloyl group is preferable.

Examples of groups that can be bonded to functional groups in the adhesive resin (I-1a) include isocyanate groups and glycidyl groups that can be bonded to hydroxyl groups or amino groups, and hydroxyl groups and amino groups that can be bonded to carboxyl groups or epoxy groups.

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

The adhesive resin (I-2a) contained in the pressure-sensitive adhesive composition (I-2) or (I-3) may be one type, or may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

In the adhesive composition (I-2) or (I-3), the ratio of the content of the adhesive resin (I-2a) to the total mass of the adhesive composition (I-2) or (I-3) is 5 to 99 mass It is preferably %.

[Energy ray curable compound]

Examples of the energy ray-curable compound in the pressure-sensitive adhesive compositions (I-1) and (I-3) include a monomer or oligomer that has an energy ray-polymerizable unsaturated group and can be cured by irradiation with energy rays.

Among the energy ray-curable compounds, monomers include, for example, trimethylolpropane tri(meth)acrylate, pentaerythritol (meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth) Polyhydric (meth)acrylates such as acrylate, 1,4-butylene glycol di(meth)acrylate, and 1,6-hexanediol (meth)acrylate; Urethane (meth)acrylate; Polyester (meth)acrylate; Polyether (meth)acrylate; Epoxy (meth)acrylate, etc. are mentioned.

Among the energy ray-curable compounds, oligomers include, for example, oligomers obtained by polymerization of the monomers exemplified above.

The energy ray-curable compounds contained in the pressure-sensitive adhesive composition (I-1) or (I-3) may be one type or two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-1), the content ratio of the energy ray-curable compound to the total mass of the pressure-sensitive adhesive composition (I-1) is preferably 1 to 95% by mass.

In the pressure-sensitive adhesive composition (I-3), the content of the energy ray-curable compound is preferably 0.01 to 300 parts by mass based on 100 parts by mass of the content of the pressure-sensitive adhesive resin (I-2a).

[Crosslinking agent]

In the case of using the above acrylic polymer having a structural unit derived from a functional group-containing monomer in addition to the structural unit derived from an alkyl (meth)acrylate as the adhesive resin (I-1a), the pressure-sensitive adhesive composition (I-1) is additionally a crosslinking agent. It is preferable to contain.

In addition, in the case of using the acrylic polymer having structural units derived from the same functional group-containing monomer as in the adhesive resin (I-1a), for example, as the adhesive resin (I-2a), the adhesive composition (I-2) Alternatively, (I-3) may further contain a crosslinking agent.

The crosslinking agent reacts with the functional group, for example, to crosslink the adhesive resins (I-1a) or the adhesive resins (I-2a).

Examples of the crosslinking agent include isocyanate crosslinking agents (crosslinking agents having an isocyanate group) such as tolylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, and adducts of these diisocyanates; Epoxy-based crosslinking agents such as ethylene glycol glycidyl ether (crosslinking agents having a glycidyl group); Aziridine-based crosslinking agents (crosslinking agents having an aziridinyl group) such as hexa[1-(2-methyl)-aziridinyl]triphosphatriazine; Metal chelate-based crosslinking agents such as aluminum chelate (crosslinking agents having a metal chelate structure); Isocyanurate-based crosslinking agents (crosslinking agents having an isocyanuric acid skeleton), and the like.

The crosslinking agent contained in the pressure-sensitive adhesive compositions (I-1) to (I-3) may be one type or two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

The content of the crosslinking agent in the pressure-sensitive adhesive composition (I-) is preferably 0.01 to 50 parts by mass based on 100 parts by mass of the adhesive resin (I-1a), and, for example, 0.01 to 35 parts by mass and 0.01 to 20 parts by mass. It may be any of wealth.

In the pressure-sensitive adhesive composition (I-2) or (I-3), the content of the crosslinking agent is preferably 0.01 to 50 parts by mass based on 100 parts by mass of the content of the adhesive resin (I-2a), for example, 0.01 to 35 Any of a mass part, 0.01-20 mass part, and 0.01-10 mass part may be sufficient.

[Photopolymerization initiator]

The pressure-sensitive adhesive compositions (I-1) to (I-3) may further contain a photoinitiator. Even if the pressure-sensitive adhesive compositions (I-1) to (I-3) containing a photoinitiator are irradiated with relatively low energy energy rays such as ultraviolet rays, the curing reaction sufficiently proceeds.

Examples of the photopolymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, methyl benzoin benzoate, and benzoin dimethyl ketal. Phosphorus compounds; Acetophenone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 2,2-dimethoxy-1,2-diphenylethan-1-one, 2-hydroxy-1-(4 Acetophenone compounds such as -(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropan-1-one; Acylphosphine oxide compounds such as bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide; Sulfide compounds such as benzylphenyl sulfide and tetramethylthiuram monosulfide; Α-ketol compounds such as 1-hydroxycyclohexylphenyl ketone; Azo compounds such as azobisisobutyronitrile; Titanocene compounds such as titanocene; Thioxanthone compounds such as thioxanthone; Peroxide compounds; Diketone compounds such as diacetyl; benzyl; Dibenzyl; Benzophenone; 2,4-diethyl thioxanthone; 1,2-diphenylmethane; 2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone; And quinone compounds such as 1-chloroanthraquinone and 2-chloroanthraquinone.

Further, as the photopolymerization initiator, for example, a photosensitizer such as amine may be used.

The photopolymerization initiators contained in the pressure-sensitive adhesive compositions (I-1) to (I-3) may be one type or two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-1), the content of the photoinitiator is preferably 0.01 to 20 parts by mass based on 100 parts by mass of the energy ray-curable compound.

The content of the photopolymerization initiator in the pressure-sensitive adhesive composition (I-2) is preferably 0.01 to 20 parts by mass based on 100 parts by mass of the adhesive resin (I-2a), and, for example, 0.01 to 10 parts by mass and 0.01 to 5 parts by mass. Any of the mass parts may be used.

In the adhesive composition (I-3), the content of the photoinitiator is preferably 0.01 to 20 parts by mass based on 100 parts by mass of the total content of the adhesive resin (I-2a) and the energy ray-curable compound.

The gel fraction of the pressure-sensitive adhesive compositions (I-1) to (I-3) can be adjusted by the molecular weight of the polymer used as the material of the pressure-sensitive adhesive composition, the amount of the functional group as a crosslinking starting point, the amount of the crosslinking agent, and the like. For example, by increasing the blending amount of the crosslinking agent, the gel fraction of the pressure-sensitive adhesive composition can be increased.

[Other additives]

The pressure-sensitive adhesive compositions (I-1) to (I-3) may contain other additives which do not correspond to any of the above-described components within a range that does not impair the effects of the present invention.

Examples of the above other additives include antistatic agents, antioxidants, softeners (plasticizers), fillers, rust inhibitors, coloring agents (pigments, dyes), sensitizers, tackifiers, reaction retardants, crosslinking accelerators (catalysts), etc. Known additives are mentioned.

On the other hand, the reaction retarding agent is, for example, in the pressure-sensitive adhesive compositions (I-1) to (I-3) during storage by the action of a catalyst incorporated in the pressure-sensitive adhesive compositions (I-1) to (I-3). , It is to suppress the progress of the crosslinking reaction which is not intended. Examples of the reaction retarding agent include forming a chelate complex by chelate to a catalyst, and more specifically, one having two or more carbonyl groups (-C(=O)-) in one molecule. .

The other additives contained in the pressure-sensitive adhesive compositions (I-1) to (I-3) may be one type or two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

The content of the other additives in the pressure-sensitive adhesive compositions (I-1) to (I-3) is not particularly limited, and may be appropriately selected according to the kind.

[menstruum]

The pressure-sensitive adhesive compositions (I-1) to (I-3) may contain a solvent. When the adhesive compositions (I-1) to (I-3) contain a solvent, the application aptitude to the surface to be coated is improved.

Incidentally, in the present specification, "solvent" is a concept including not only dissolving the target component, but also a dispersion medium dispersing the target component, unless otherwise specified.

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 (carboxylic acid ester); Ethers such as tetrahydrofuran and dioxane; Aliphatic hydrocarbons such as cyclohexane and n-hexane; Aromatic hydrocarbons such as toluene and xylene; Alcohol, such as 1-propanol and 2-propanol, etc. are mentioned.

The number of solvents contained in the pressure-sensitive adhesive compositions (I-1) to (I-3) may be one type or two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

The content of the solvent in the pressure-sensitive adhesive compositions (I-1) to (I-3) is not particularly limited and may be appropriately adjusted.

<<The manufacturing method of the adhesive composition>>

The pressure-sensitive adhesive compositions such as pressure-sensitive adhesive compositions (I-1) to (I-3) are obtained by blending the pressure-sensitive adhesive and, if necessary, each component for constituting the pressure-sensitive adhesive composition such as components other than the pressure-sensitive adhesive.

The order of addition at the time of blending each component is not particularly limited, and two or more components may be added at the same time.

The method of mixing each component at the time of mixing is not particularly limited, and a method of mixing by rotating a stirrer or a stirring blade, etc.; Mixing using a mixer; What is necessary is just to select suitably from well-known methods, such as a method of adding ultrasonic waves and mixing.

The temperature and time at the time of addition and mixing of each component are not particularly limited as long as each compounding component does not deteriorate, and may be appropriately adjusted, but the temperature is preferably 15 to 30°C.

◇ Film for forming a protective film

The protective film-forming film can be laminated with a support sheet provided with a pressure-sensitive adhesive layer, for example, as described later, to constitute a protective film-forming composite sheet.

The protective film-forming film forms a protective film for protecting the work and any location of the work-processed object. When the work is a semiconductor wafer, by using the film for forming a protective film of the present embodiment, the side opposite to the circuit formation surface of the semiconductor wafer and the semiconductor chip (in this specification, it may be referred to as "the back side" in any case. ) To form a protective film. In this specification, the work-worked product with a protective film in this way is sometimes referred to as a "work-worked product with a protective film", and a semiconductor chip provided with a protective film on the back surface is sometimes referred to as a "semiconductor chip with a protective film".

The film for forming a protective film is soft and can be easily affixed to an object to be pasted, such as a work and a work-processed object.

The film for forming a protective film may function as a protective film by its curing, or may function as a protective film in an uncured state. The film for forming a protective film, which functions as a protective film in an uncured state, can be regarded as forming a protective film in the step of being affixed to a target location of the work, for example.

As described above, the film for forming a protective film may be curable or non-curable.

The film for forming a curable protective film may be thermosetting and energy ray-curable, and may have both thermosetting and energy ray-curable properties.

In the present specification, "non-curable" means a property that is not cured by any means such as heating or irradiation with energy rays.

In the case of forming a protective film by thermally curing the protective film-forming film, unlike the case of curing by irradiation of energy rays, the protective film-forming film is sufficiently cured by heating even when its thickness is thickened. Can be formed. Further, by using a common heating means such as a heating oven, a number of films for forming a protective film can be collectively heated and thermally cured.

In the case of forming a protective film by curing the protective film-forming film by irradiation with energy rays, unlike the case of thermosetting, the composite sheet for forming a protective film does not need to have heat resistance, and constitutes a wide range of composite sheets for forming a protective film. can do. Further, it can be cured in a short time by irradiation with energy rays.

In the case where the protective film-forming film is not cured and used as a protective film, the curing step can be omitted, and thus a work product having a protective film formed thereon can be manufactured in a simplified step.

Regardless of whether the film for forming a protective film is curable or non-curable, and when curable, regardless of whether it is thermosetting or energy ray-curable, the film for forming a protective film may consist of one layer (single layer), or two or more layers. It may consist of multiple layers. When the film for protective film formation is made of a plurality of layers, the plurality of layers may be the same or different from each other, and the combination of the plurality of layers is not particularly limited.

Regardless of whether the film for forming a protective film is curable or non-curable, and when curable, regardless of whether it is thermosetting or energy ray-curable, the thickness of the protective film-forming film is preferably 1 to 100 μm, and 3 to 80 It is more preferable that it is µm, and it is particularly preferable that it is 5 to 60 µm, and for example, any of 5 to 40 µm and 5 to 20 µm may be used. When the thickness of the protective film-forming film is equal to or greater than the lower limit, a protective film having a higher protective ability can be formed. When the thickness of the protective film-forming film is less than or equal to the upper limit, excessive thickness can be avoided.

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 is the sum of all layers constituting the protective film-forming film. Means the thickness of.

In the composite sheet for forming a protective film of the first embodiment, the glass transition temperature (Tg) of the film for forming a protective film is preferably 3°C or higher, more preferably 5°C or higher, even more preferably 15°C or higher, for example For example, it is 10 degreeC or more and 20 degreeC or more. When the glass transition temperature of the protective film forming film is equal to or higher than the lower limit, it is possible to suppress the mutual migration of components between the energy ray-curable pressure-sensitive adhesive layer and the protective film-forming film before energy ray curing, and the semiconductor chip on which the protective film is formed is supported. When picked up from, the effect of being able to peel off the semiconductor chip on which the protective film is formed from the support sheet without peeling between the semiconductor chip and the protective film is further improved.

In the composite sheet for forming a protective film of the second embodiment, the glass transition temperature (Tg) of the film for forming a protective film is 3°C or higher, preferably 5°C or higher, more preferably 15°C or higher, and even more preferably 20°C or higher. And, for example, 10°C or higher. Since the glass transition temperature of the protective film-forming film is not less than the above lower limit, even if the gel fraction of the pressure-sensitive adhesive layer before energy ray curing is 20% or more and less than 80%, between the energy ray-curable pressure-sensitive adhesive layer and the protective film-forming film before energy ray curing Transition of the components can be suppressed, and when the semiconductor chip with the protective film is picked up from the support sheet, it becomes possible to peel the semiconductor chip with the protective film from the support sheet without being peeled between the semiconductor chip and the protective film.

In the protective film-forming composite sheet of the first embodiment and the protective film-forming composite sheet of the second embodiment, the loss modulus E" at 23°C of the protective film-forming film is preferably 3 MPa or more, and more preferably 5 MPa or more. And, for example, 10 MPa or more, 15 MPa or more, 20 MPa or more, 25 MPa or more, 30 MPa or more, 40 MPa or more, 50 MPa or more.

The upper limit of the loss modulus E" at 23° C. of the protective film-forming film is not particularly limited. For example, a film for protective film formation of 100 MPa or less can be easily produced.

The method of measuring the glass transition temperature (Tg) of the film for forming a protective film and the loss modulus E" at 23°C can be measured by a known method. Specifically, it can be measured by the following method.

A test piece was prepared by laminating the sample to a thickness of about 200 µm and processing the obtained laminate to a size of 4 mm in width and 30 mm in length (chuck distance). This test piece was subjected to an automatic dynamic viscoelastic tester (manufactured by Orientec, product name "RheovibronDDV-0.1FP"), and the tensile loss modulus E" at 23°C was measured at a measurement frequency of 1 Hz, and the peak temperature of tanδ at that time. Is taken as the glass transition temperature (Tg).

<<Composition for forming a protective film>>

The film for forming a protective film can be formed using a composition for forming a protective film containing the constituent material. For example, the film for forming a protective film can be formed by coating the composition for forming a protective film on the surface to be formed and drying as necessary. In the composition for forming a protective film, the content ratio between components that do not vaporize at room temperature is usually the same as the content ratio between the components in the film for forming a protective film.

The film for forming a thermosetting protective film can be formed using a composition for forming a thermosetting protective film, the film for forming an energy ray-curable protective film can be formed using a composition for forming an energy ray-curable protective film, and the film for forming a non-curable protective film is non-curable It can be formed using a composition for forming a chemical conversion protective film. On the other hand, in the present specification, when the protective film-forming film has properties of both thermosetting and energy ray curing properties, when the contribution of the thermosetting of the protective film-forming film to the formation of the protective film is greater than that of the energy ray curing, the protective film is formed. The dragon film is treated as being thermosetting. Conversely, when the contribution of the energy ray curing of the protective film-forming film to the formation of the protective film is greater than that of thermal curing, the protective film-forming film is treated as being energy ray-curable.

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

Regardless of whether the protective film-forming film is curable or non-curable, and in the case of curing, regardless of whether it is thermosetting or energy ray-curable, the drying conditions of the composition for forming a protective film are not particularly limited. However, when the composition for forming a protective film contains a solvent described later, it is preferable to heat-dry it. In addition, the composition for forming a protective film containing a solvent is preferably heated and dried at 70 to 130°C for 10 seconds to 5 minutes. However, it is preferable to heat-dry the composition for thermosetting protective film formation so that this composition itself and the film for thermosetting protective film formation formed from this composition do not thermoset.

Hereinafter, a film for forming a thermosetting protective film, a film for forming an energy ray-curable protective film, and a film for forming a non-curable protective film will be sequentially described.

◎ Film for forming a thermosetting protective film

The curing conditions for forming the protective film by affixing the film for forming a thermosetting protective film to the intended location of the work and thermally curing are not particularly limited as long as the degree of curing of the protective film sufficiently exhibits its function, and thermosetting It may be appropriately selected according to the kind of the film for forming a protective film.

For example, the heating temperature at the time of thermosetting of the thermosetting protective film forming film is preferably 100 to 200°C, more preferably 110 to 180°C, and particularly preferably 120 to 170°C. Further, the heating time at the time of thermal curing is preferably 0.5 to 5 hours, more preferably 0.5 to 3 hours, and particularly preferably 1 to 2 hours.

As a preferable film for thermosetting protective film formation, what contains a polymer component (A) and a thermosetting component (B) is mentioned, for example. The polymer component (A) is a component that can be regarded as formed by a polymerization reaction of a polymerizable compound. In addition, the thermosetting component (B) is a component capable of curing (polymerization) reaction using heat as a trigger of the reaction. In addition, in this specification, a polycondensation reaction is also included in a polymerization reaction.

<Composition for forming a thermosetting protective film (III-1)>

A preferred composition for forming a thermosetting protective film is, for example, a composition for forming a thermosetting protective film containing the polymer component (A) and the thermosetting component (B) (III-1) (in this specification, simply ``composition (III-1) It may be abbreviated as ").

[Polymer component (A)]

The polymer component (A) is a component for imparting film-forming properties, flexibility, and the like to the film for forming a thermosetting protective film.

The composition (III-1) and the polymer component (A) contained in the film for forming a thermosetting protective film may be only one type, or may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

Examples of the polymer component (A) include acrylic resins, polyesters, urethane resins, acrylic urethane resins, silicone resins, rubber resins, phenoxy resins, and thermoplastic polyimides, and acrylic resins are preferable.

Known acrylic polymers are exemplified as the acrylic resin in the polymer component (A).

It is preferable that it is 10000-2000000, and, as for the weight average molecular weight (Mw) of an acrylic resin, it is more preferable that it is 100000-1500000. When the weight average molecular weight of the acrylic resin is not less than the above lower limit, the shape stability (stability with time at the time of storage) of the film for forming a thermosetting protective film is improved. In addition, when the weight average molecular weight of the acrylic resin is less than or equal to the above upper limit, the film for forming a thermosetting protective film is easier to follow on the uneven surface of the adherend, and the occurrence of voids between the adherend and the film for forming a thermosetting protective film is more suppressed. .

In addition, in this specification, a "weight average molecular weight" is a polystyrene conversion value measured by a gel permeation chromatography (GPC) method unless otherwise specified.

The glass transition temperature (Tg) of the acrylic resin is preferably 3°C or more and 70°C or less, and more preferably 3°C or more and 50°C or less. When the Tg of the acrylic resin is equal to or higher than the lower limit, it is possible to suppress the mutual migration of components between the energy ray-curable pressure-sensitive adhesive and the protective film-forming film before energy ray curing, and when picking up the semiconductor chip on which the protective film is formed from the support sheet, The effect that the semiconductor chip on which the protective film is formed can be peeled from the support sheet without peeling between the semiconductor chip and the protective film is further improved. Further, when the Tg of the acrylic resin is equal to or less than the above upper limit, the adhesion between the film for forming a thermosetting protective film and the cured product thereof is improved.

Examples of the acrylic resin include polymers of one or two or more (meth)acrylic acid esters; And copolymers of two or more monomers selected from (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N-methylolacrylamide.

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, n- (meth)acrylate. Butyl, (meth) isobutyl acrylate, (meth) acrylate sec-butyl, (meth) acrylate tert-butyl, (meth) acrylate, pentyl (meth) acrylate, (meth) heptyl acrylate, (meth) acrylate 2-ethyl Hexyl, (meth) acrylate isooctyl, (meth) acrylate n-octyl, (meth) acrylate n-nonyl, (meth) acrylate isononyl, (meth) acrylate, (meth) acrylate, (meth) acrylate Dodecyl ((meth) acrylate lauryl), (meth) acrylate tridecyl, (meth) acrylate tetradecyl ((meth) acrylate myristylus), (meth) acrylate pentadecyl, (meth) acrylate hexadecyl ((meth) (Meth) acrylate alkyl ester in which the alkyl group constituting the alkyl ester such as palmityl acrylate), (meth) acrylate heptadecyl, and (meth) acrylate octadecyl ((meth) acrylate stearyl) has a chain structure having 1 to 18 carbon atoms ;

(Meth)acrylate cycloalkyl esters such as isobornyl (meth)acrylate and dicyclopentanyl (meth)acrylate;

(Meth)acrylic acid aralkyl esters such as benzyl (meth)acrylate;

(Meth) acrylate cycloalkenyl ester, such as (meth) acrylate dicyclopentenyl ester;

(Meth)acrylic acid cycloalkenyloxyalkyl esters such as (meth)acrylate dicyclopentenyloxyethyl ester;

Imide (meth)acrylate;

Glycidyl group-containing (meth)acrylic acid esters such as glycidyl (meth)acrylate;

Hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, (meth) ) Hydroxyl group-containing (meth)acrylic acid esters such as 3-hydroxybutyl acrylic acid and 4-hydroxybutyl (meth)acrylate;

And substituted amino group-containing (meth)acrylic acid esters such as N-methylaminoethyl (meth)acrylate. Here, the "substituted amino group" means a group obtained by substituting one or two hydrogen atoms of an amino group with a group other than a hydrogen atom.

Acrylic resin, for example, in addition to the (meth) acrylic acid ester, (meth) acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene and N-methylol acrylamide one or two or more monomers selected from It may be formed by copolymerization.

The number of monomers constituting the acrylic resin may be only one, or may be two or more, and in the case of two or more, combinations and ratios thereof can be arbitrarily selected.

The acrylic resin may have a functional group capable of bonding with other compounds such as a vinyl group, a (meth)acryloyl group, an amino group, a hydroxyl group, a carboxyl group, and an isocyanate group. The functional group of the acrylic resin may be bonded to another compound via a crosslinking agent (F) to be described later, or may be directly bonded to another compound without a crosslinking agent (F). When the acrylic resin is bonded to another compound by the functional group, the reliability of the package obtained by 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 acrylic resin (hereinafter, simply abbreviated as ``thermoplastic resin'' in some cases) may be used alone without using an acrylic resin, and an acrylic resin and You may use it together. By using the thermoplastic resin, the peelability of the protective film from the supporting sheet is improved, or the film for forming a thermosetting protective film is easier to follow on the uneven surface of the adherend, and voids, etc., are generated between the adherend and the film for forming a thermosetting protective film. It may be more suppressed.

It is preferable that it is 1000-100000, and, as for the weight average molecular weight of the said thermoplastic resin, it is more preferable that it is 3000-80000.

The glass transition temperature (Tg) of the thermoplastic resin is preferably 3°C or more and 150°C or less, and more preferably 3°C or more and 120°C or less.

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

The thermoplastic resins contained in the composition (III-1) and the film for forming a thermosetting protective film may be one type or two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

The ratio of the content of the polymer component (A) to the total content of all components other than the solvent in the composition (III-1) (that is, the polymer component to the total mass of the film for forming a thermosetting protective film in the film for forming a thermosetting protective film ( The content ratio of A) is preferably 10 to 85% by mass, more preferably 15 to 70% by mass, even more preferably 20 to 60% by mass, regardless of the type of the polymer component (A). , For example, any of 20 to 45% by mass and 20 to 35% by mass may be used, and any of 35 to 60% by mass and 45 to 60% by mass may be used.

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

[Thermosetting component (B)]

The thermosetting component (B) is a component for curing the film for forming a thermosetting protective film.

The composition (III-1) and the thermosetting component (B) contained in the film for forming a thermosetting protective film may be only one type, may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

Examples of the thermosetting component (B) include epoxy-based thermosetting resins, polyimide-based resins, and unsaturated polyester resins, and epoxy-based thermosetting resins are preferred.

(Epoxy thermosetting resin)

The epoxy-based thermosetting resin consists of an epoxy resin (B1) and a thermosetting agent (B2).

The composition (III-1) and the epoxy-based thermosetting resin contained in the film for forming a thermosetting protective film may be only one type, may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

Epoxy resin (B1)

Known epoxy resins (B1) include, for example, polyfunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ether and hydrogenated products thereof, orthocresol novolac epoxy resins, dicyclopentadiene. Type epoxy resin, biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenylene skeleton type epoxy resin, and other bifunctional or higher epoxy compounds.

As the epoxy resin (B1), an epoxy resin having an unsaturated hydrocarbon group may be used. Epoxy resin having an unsaturated hydrocarbon group has higher compatibility with an acrylic resin than an epoxy resin having no unsaturated hydrocarbon group. For this reason, the use of an epoxy resin having an unsaturated hydrocarbon group improves the reliability of a workpiece formed with a protective film obtained by using the composite sheet for forming a protective film.

Examples of the epoxy resin having an unsaturated hydrocarbon group include a compound 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 is obtained, for example, by adding (meth)acrylic acid or a derivative thereof to an epoxy group.

In addition, examples of the epoxy resin having an unsaturated hydrocarbon group include compounds in which a group having an unsaturated hydrocarbon group is directly bonded to the aromatic ring constituting the epoxy resin.

The unsaturated hydrocarbon group is a polymerizable unsaturated group, and specific examples thereof include ethenyl group (vinyl group), 2-propenyl group (allyl group), (meth)acryloyl group, (meth)acrylamide group, and the like, Acryloyl groups are preferred.

The number average molecular weight of the epoxy resin (B1) is not particularly limited, but from the viewpoint of the curability of the film for forming a thermosetting protective film, and the strength and heat resistance of the protective film that is the cured product, it is preferably 300 to 30,000, more preferably 300 to 10000. It is preferable, and it is especially preferable that it is 300-3000.

It is preferable that it is 100-1000 g/eq, and, as for the epoxy equivalent of the epoxy resin (B1), it is more preferable that it is 150-950 g/eq.

As for the epoxy resin (B1), 1 type may be used individually, 2 or more types may be used together, and when 2 or more types are used together, their combination and ratio can be arbitrarily selected.

·Heat curing agent (B2)

The thermal curing agent (B2) functions as a curing agent for the epoxy resin (B1).

Examples of the thermosetting agent (B2) include a compound having two or more functional groups capable of reacting with an epoxy group per molecule. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group, a group in which an acid group is anhydride, and the like, and a phenolic hydroxyl group, an amino group, or an acid group is preferably an anhydride group. It is more preferable that it is a hydroxyl group or an amino group.

Among the thermal curing agents (B2), examples of the phenolic curing agent having a phenolic hydroxyl group include polyfunctional phenol resins, biphenols, novolac type phenol resins, dicyclopentadiene type phenol resins, aralkyl type phenol resins, and the like. I can.

Among the thermal curing agents (B2), examples of the amine curing agent having an amino group include dicyandiamide and the like.

The thermosetting agent (B2) may have an unsaturated hydrocarbon group.

Examples of the thermosetting agent (B2) having an unsaturated hydrocarbon group include compounds obtained by substituting a part of the hydroxyl group of a phenol resin with a group having an unsaturated hydrocarbon group, and a compound obtained by directly bonding a group having an unsaturated hydrocarbon group to the aromatic ring of the phenol resin. I can.

The unsaturated hydrocarbon group in the thermosetting agent (B2) is the same as the unsaturated hydrocarbon group in the epoxy resin having the above-described unsaturated hydrocarbon group.

When a phenolic curing agent is used as the thermal curing agent (B2), it is preferable that the thermal curing agent (B2) has a high softening point or glass transition temperature from the viewpoint of improving the peelability of the protective film from the supporting sheet.

Among the thermosetting agents (B2), for example, the number average molecular weight of resin components such as polyfunctional phenol resin, novolak type phenol resin, dicyclopentadiene type phenol resin, and aralkyl type phenol resin is preferably 300 to 30,000, It is more preferable that it is 400-10000, and it is especially preferable that it is 500-3000.

Among the thermosetting agents (B2), for example, the molecular weight of the non-resin component such as biphenol and dicyandiamide is not particularly limited, but is preferably 60 to 500, for example.

The thermosetting agent (B2) may be used singly or in combination of two or more, and when two or more of them are used in combination, combinations and ratios thereof can be arbitrarily selected.

The content of the thermosetting agent (B2) in the composition (III-1) and the film for forming a thermosetting protective film is preferably 0.1 to 100 parts by mass, and 0.5 to 50 parts by mass based on 100 parts by mass of the epoxy resin (B1). It is more preferable and, for example, any of 0.5 to 25 parts by mass, 0.5 to 10 parts by mass, and 0.5 to 5 parts by mass may be used. When the content of the thermosetting agent (B2) is equal to or greater than the lower limit, the curing of the film for forming a thermosetting protective film is more likely to proceed. When the content of the thermosetting agent (B2) is equal to or less than the upper limit, the moisture absorption rate of the film for forming a thermosetting protective film is reduced, and the reliability of the package obtained by using the composite sheet for forming a protective film is further improved.

In the composition (III-1) and the film for forming a thermosetting protective film, the content of the thermosetting component (B) (for example, the total content of the epoxy resin (B1) and the thermosetting agent (B2)) is the content of the polymer component (A). It is preferably 5 to 120 parts by mass, more preferably 5 to 80 parts by mass, for example, 5 to 40 parts by mass, 5 to 20 parts by mass, and any of 5 to 10 parts by mass may be used. Any of 40 to 80 parts by mass, 50 to 75 parts by mass, and 60 to 75 parts by mass may be used. When the content of the thermosetting component (B) is within such a range, for example, the adhesion between the cured product of the protective film-forming film and the support sheet is suppressed, and the peelability of the support sheet is improved.

[Hardening accelerator (C)]

The composition (III-1) and the film for forming a thermosetting protective film may contain a curing accelerator (C). The curing accelerator (C) is a component for adjusting the curing rate of the composition (III-1).

Preferred curing accelerators (C) include tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol; 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5 Imidazoles such as hydroxymethylimidazole (imidazole in which at least one hydrogen atom is substituted with a group other than a hydrogen atom); Organic phosphines such as tributylphosphine, diphenylphosphine, and triphenylphosphine (phosphine in which at least one hydrogen atom is substituted with an organic group); Tetraphenyl boron salts, such as tetraphenyl phosphonium tetraphenyl borate and triphenyl phosphine tetraphenyl borate, etc. are mentioned.

The composition (III-1) and the curing accelerator (C) contained in the film for forming a thermosetting protective film may be only one type, may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

When using a curing accelerator (C), the content of the curing accelerator (C) in the composition (III-1) and the film for forming a thermosetting protective film is 0.01 to 10 parts by mass based on 100 parts by mass of the thermosetting component (B). It is preferable and it is more preferable that it is 0.1-7 mass parts. When the content of the curing accelerator (C) is more than the lower limit, the effect of using the curing accelerator (C) is more remarkably obtained. When the content of the curing accelerator (C) is less than or equal to the upper limit, for example, the high polarity curing accelerator (C) moves to the adhesive interface side with the adherend in the film for forming a thermosetting protective film under high temperature and high humidity conditions and segregates. The inhibitory effect increases. As a result, the reliability of the workpiece formed with the protective film obtained by using the composite sheet for forming a protective film is further improved.

[Filling material (D)]

The composition (III-1) and the film for forming a thermosetting protective film may contain a filler (D). When the thermosetting protective film-forming film contains the filler (D), the thermosetting protective film-forming film and its cured product (i.e., the protective film) facilitate adjustment of the thermal expansion coefficient, and by optimizing this thermal expansion coefficient for the object to be formed of the protective film, The reliability of the workpiece formed with the protective film obtained by using the composite sheet for forming a protective film is further improved. Further, when the film for forming a thermosetting protective film contains the filler (D), the moisture absorption rate of the protective film can be reduced or the heat dissipation property can be improved.

The filler (D) may be any of an organic filler and an inorganic filler, but is preferably an inorganic filler.

Preferred inorganic fillers include powders such as silica, alumina, talc, calcium carbonate, titanium white, bengala, silicon carbide and boron nitride; Beads in which these inorganic fillers are spheroidized; Surface modified products of these inorganic fillers; Single crystal fibers of these inorganic fillers; Glass fiber, etc. are mentioned.

Among these, the inorganic filler is preferably silica or alumina, and more preferably silica.

The composition (III-1) and the filler (D) contained in the film for forming a thermosetting protective film may be one type or two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

In the composition (III-1), the ratio of the content of the filler (D) to the total content of all components other than the solvent (that is, the filler (D) to the total mass of the film for forming a thermosetting protective film in the film for forming a thermosetting protective film. ) Content ratio) is preferably 50% by mass or more, and more preferably 55% by mass or more. The upper limit of the content ratio of the filler (D) is preferably 80% by mass or less, preferably 70% by mass or less, and, for example, 50% by mass or more and 80% by mass or less, and 55% by mass or more and 80% by mass or less. It may be, and any of 50% by mass or more and 70% by mass or less, and 55% by mass or more and 70% by mass or less may be used. When the ratio is within such a range, it is possible to suppress mutual migration of components between the energy ray-curable pressure-sensitive adhesive and the protective film-forming film before energy ray curing.

[Coupling agent (E)]

The composition (III-1) and the film for forming a thermosetting protective 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 film for forming a thermosetting protective film to an adherend can be improved. Further, by using the coupling agent (E), the cured product of the film for forming a thermosetting protective film does not impair heat resistance and improves water resistance.

The coupling agent (E) is preferably a compound having a functional group capable of reacting with a functional group of the polymer component (A), the thermosetting component (B), and the like, and more preferably a silane coupling agent.

Preferred silane coupling agents include, for example, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyltriethoxysilane, and 3-glycidyloxypropyltrimethoxysilane. Cidyloxymethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-( 2-aminoethylamino)propyltrimethoxysilane, 3-(2-aminoethylamino)propylmethyldiethoxysilane, 3-(phenylamino)propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3 -Ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, bis(3-triethoxysilylpropyl)tetrasulfane, methyltrimethoxysilane, methyltri Ethoxysilane, vinyl trimethoxysilane, vinyl triacetoxysilane, imidazole silane, etc. are mentioned.

The composition (III-1) and the coupling agent (E) contained in the film for forming a thermosetting protective film may be only one type, may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

When a coupling agent (E) is used, in the composition (III-1) and the film for forming a thermosetting protective film, the content of the coupling agent (E) is 100 parts by mass of the total content of the polymer component (A) and the thermosetting component (B). It is preferably 0.03 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and particularly preferably 0.1 to 2 parts by mass. When the content of the coupling agent (E) is greater than or equal to the lower limit, the use of the coupling agent (E), such as improving the dispersibility of the filler (D) in the resin, or improving the adhesion of the film for forming a thermosetting protective film to the adherend. The effect is obtained more remarkably. In addition, when the content of the coupling agent (E) is equal to or less than the upper limit, generation of outgas is further suppressed.

[Crosslinking agent (F)]

When using a polymer component (A) having a functional group such as a vinyl group, a (meth)acryloyl group, an amino group, a hydroxyl group, a carboxyl group, an isocyanate group, which can be bonded to other compounds such as the above-described acrylic resin, is used, the composition (III-1) ) And the film for forming a thermosetting protective film may contain a crosslinking agent (F). The crosslinking agent (F) is a component for crosslinking by bonding the functional group in the polymer component (A) with another compound, and by crosslinking in this manner, the initial adhesive force and cohesive force of the film for forming a thermosetting protective film can be adjusted.

Examples of the crosslinking agent (F) include an organic polyvalent isocyanate compound, an organic polyvalent imine compound, a metal chelate type crosslinking agent (a crosslinking agent having a metal chelate structure), an aziridine type crosslinking agent (a crosslinking agent having an aziridinyl group), and the like.

The crosslinking agent (F) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one type, or may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

When using the crosslinking agent (F), the content of the crosslinking agent (F) in the composition (III-1) is preferably 0.01 to 20 parts by mass, and 0.1 to 10 parts by mass based on 100 parts by mass of the polymer component (A). It is more preferable and it is especially preferable that it is 0.5-5 mass parts. When the content of the crosslinking agent (F) is more than the lower limit, the effect of using the crosslinking agent (F) is more remarkably obtained. Further, when the content of the crosslinking agent (F) is equal to or less than the upper limit, excessive use of the crosslinking agent (F) is suppressed.

[Energy ray curable resin (G)]

The composition (III-1) and the film for forming a thermosetting protective film may contain an energy ray-curable resin (G). Since the film for thermosetting protective film formation contains an energy ray-curable resin (G), its properties can be changed by irradiation with energy rays.

The energy ray-curable resin (G) is obtained by polymerizing (curing) an energy ray-curable compound.

Examples of the energy ray-curable compound include a compound having at least one polymerizable double bond in the molecule, and an acrylate compound having a (meth)acryloyl group is preferable.

Examples of the acrylate-based compound include trimethylolpropane tri(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylic. Rate, dipentaerythritol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,4-butylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) ) (Meth)acrylate containing a chain aliphatic skeleton such as acrylate; Cyclic aliphatic skeleton-containing (meth)acrylates such as dicyclopentanyldi(meth)acrylate; Polyalkylene glycol (meth)acrylates such as polyethylene glycol di(meth)acrylate; Oligoester (meth)acrylate; Urethane (meth)acrylate oligomers; Epoxy modified (meth)acrylate; Polyether (meth)acrylate other than the polyalkylene glycol (meth)acrylate; Itaconic acid oligomer, etc. are mentioned.

It is preferable that it is 100-30000, and, as for the weight average molecular weight of the said energy ray-curable compound, it is more preferable that it is 300-10000.

The energy ray-curable compounds used for polymerization may be only one type, may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

The energy ray-curable resin (G) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one type, may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

When using an energy ray-curable resin (G), the content ratio of the energy ray-curable resin (G) to the total mass of the composition (III-1) in the composition (III-1) is preferably 1 to 95% by mass. And, it is more preferable that it is 5 to 90 mass %, and it is especially preferable that it is 10 to 85 mass %.

[Photopolymerization initiator (H)]

When the composition (III-1) and the film for forming a thermosetting protective film contain an energy ray-curable resin (G), even if it contains a photopolymerization initiator (H) in order to efficiently proceed the polymerization reaction of the energy ray-curable resin (G). do.

As the photoinitiator (H) in the composition (III-1), the same as the photoinitiator which may be contained in the pressure-sensitive adhesive composition described above is mentioned, for example.

The photopolymerization initiators (H) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one type, may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

When using a photoinitiator (H), the content of the photoinitiator (H) in the composition (III-1) is preferably 0.1 to 20 parts by mass based on 100 parts by mass of the content of the energy ray-curable resin (G), 1 It is more preferable that it is -10 mass parts, and it is especially preferable that it is 2-5 mass parts.

[Coloring agent (I)]

It is preferable that the composition (III-1) and the film for forming a thermosetting protective film contain the colorant (I). By using the colorant (I), a film for forming a protective film having a transmittance of light (266 nm) of 60% or less can be produced more easily.

As the colorant (I), well-known things, such as an inorganic pigment, an organic pigment, and an organic dye, are mentioned, for example.

The organic pigments and organic dyes include, for example, an aminium pigment, a cyanine pigment, a merocyanine pigment, a chromonium pigment, a squarylium pigment, an azrenium pigment, a polymethine pigment, a naphthoquinone pigment. , Pyryllium pigments, phthalocyanine pigments, naphthalocyanine pigments, naphtholactam pigments, azo pigments, condensed azo pigments, indigo pigments, perinone pigments, perylene pigments, dioxazine pigments, quinacridone pigments, Isoindolinone dye, quinophthalone dye, pyrrole dye, thioindigo dye, metal complex dye (metal complex dye), dithiol metal complex dye, indolephenol dye, triarylmethane dye, anthra And quinone-based dyes, naphthol-based dyes, azomethine-based dyes, benzimidazolone-based dyes, pyrantrone-based dyes, and tren-based dyes.

Examples of the inorganic pigments include carbon black, cobalt pigments, iron pigments, chromium pigments, titanium pigments, vanadium pigments, zirconium pigments, molybdenum pigments, ruthenium pigments, platinum pigments, ITO (indium pigments). Tin oxide)-based dyes, ATO (antimony tin oxide)-based dyes, and the like.

The composition (III-1) and the colorant (I) contained in the film for forming a thermosetting protective film may be one type or two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

When using the coloring agent (I), the content of the coloring agent (I) in the film for forming a thermosetting protective film may be appropriately adjusted according to the purpose. For example, by adjusting the content of the colorant (I) in the film for forming a thermosetting protective film and adjusting the light transmittance of the protective film, printing visibility when laser printing is performed on the protective film can be adjusted. Further, by adjusting the content of the colorant (I) in the film for forming a thermosetting protective film, the designability of the protective film can be improved or it is possible to make it difficult to show a grinding trace on the back surface of the semiconductor wafer. Taking this point into consideration, the ratio of the content of the colorant (I) to the total content of all components other than the solvent in the composition (III-1) (that is, the total mass of the film for forming a thermosetting protective film in the film for forming a thermosetting protective film) The content ratio of the coloring agent (I) to) is preferably 0.1 to 10% by mass, more preferably 0.1 to 7.5% by mass, and particularly preferably 0.1 to 5% by mass. When the ratio is greater than or equal to the lower limit, the effect of using the colorant (I) is more remarkably obtained. Further, when the ratio is equal to or less than the upper limit, excessive decrease in light transmittance of the film for forming a thermosetting protective film is suppressed.

[Universal Additive (J)]

The composition (III-1) and the film for forming a thermosetting protective film may contain a general-purpose additive (J) within a range that does not impair the effects of the present invention.

The general-purpose additive (J) may be a known one, may be arbitrarily selected according to the purpose, and is not particularly limited, but preferable examples include a plasticizer, an antistatic agent, an antioxidant, a gettering agent, an ultraviolet absorber, and the like. .

The composition (III-1) and the general-purpose additives (J) contained in the film for forming a thermosetting protective film may be one type or two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

The content of the composition (III-1) and the general-purpose additive (J) in the film for forming a thermosetting protective film is not particularly limited, and may be appropriately selected according to the purpose.

[menstruum]

It is preferable that the composition (III-1) further contains a solvent. The composition (III-1) containing a solvent becomes good in handleability.

The solvent is not particularly limited, but preferable examples thereof include hydrocarbons such as toluene and xylene; Alcohols such as methanol, ethanol, 2-propanol, isobutyl alcohol (2-methylpropan-1-ol), and 1-butanol; Esters such as ethyl acetate; Ketones such as acetone and methyl ethyl ketone; Ethers such as tetrahydrofuran; And amides (compounds having an amide bond) such as dimethylformamide and N-methylpyrrolidone.

The number of solvents contained in the composition (III-1) may be only one type, or may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

As the solvent contained in the composition (III-1), more preferable ones include, for example, methyl ethyl ketone, toluene, ethyl acetate, etc., in order to more evenly mix the components contained in the composition (III-1). Can be lifted.

The content of the solvent in the composition (III-1) is not particularly limited, and for example, it may be appropriately selected according to the kind of components other than the solvent.

<Method of producing a composition for forming a thermosetting protective film>

Compositions for forming a thermosetting protective film such as composition (III-1) are obtained by blending each component for constituting the composition.

The composition for forming a thermosetting protective film can be prepared in the same manner as in the case of the pressure-sensitive adhesive composition described above, except that the types of the blending components are different.

◎ Film for forming energy ray-curable protective film

The energy ray-curable protective film-forming film is adhered to the target location of the work, and the curing conditions at the time of energy ray-curing and forming the protective film are not particularly limited as long as the degree of curing is such that the protective film sufficiently exhibits its function, What is necessary is just to select suitably according to the kind of the film for energy ray-curable protective film formation.

For example, at the time of energy ray curing of the energy ray-curable protective film-forming film, the illuminance of the energy ray is preferably 120 to 280 mW/cm 2. In addition, it is preferable that the amount of light of the energy ray at the time of curing is 100 to 1000 mJ/cm 2.

Examples of the film for forming an energy ray-curable protective film include those containing the energy ray-curable component (a), and are preferably those containing the energy ray-curable component (a) and a filler.

In the film for forming an energy ray-curable protective film, the energy ray-curable component (a) is preferably uncured, preferably having adhesiveness, and more preferably uncured and having adhesiveness.

<Composition for energy ray-curable protective film formation (IV-1)>

As a preferable composition for forming an energy ray-curable protective film, for example, the composition (IV-1) for forming an energy ray-curable protective film containing the energy ray-curable component (a) (in this specification, simply ``composition (IV-1) )” and may be abbreviated).

[Energy ray curable component (a)]

The energy ray-curable component (a) is a component that is cured by irradiation with energy rays, and provides film-forming properties or flexibility to the film for forming an energy ray-curable protective film, and is also a component for forming a hard protective film after curing. Do.

Examples of the energy ray-curable component (a) include a polymer (a1) having an energy ray-curable group having a weight average molecular weight of 80000 to 2000000 and a compound (a2) having an energy ray-curable group having a molecular weight of 100 to 800,000. . The polymer (a1) may be at least partially crosslinked with a crosslinking agent or may not be crosslinked.

(Polymer (a1) having an energy ray-curable group and a weight average molecular weight of 80000 to 2000000)

Examples of the polymer (a1) having an energy ray-curable group having a weight average molecular weight of 80000 to 2000000 include an acrylic polymer (a11) having a functional group capable of reacting with a group of other compounds, a group reacting with the functional group, and an energy ray-curable double An acrylic resin (a1-1) obtained by reacting an energy ray-curable compound (a12) having an energy ray-curable group such as a bond can be mentioned.

Examples of the functional groups capable of reacting with groups of other compounds include a hydroxyl group, a carboxyl group, an amino group, a substituted amino group (a group obtained by substituting one or two hydrogen atoms of the amino group with a group other than a hydrogen atom), and an epoxy group. . However, from the viewpoint of preventing corrosion of circuits such as a workpiece or a workpiece, the functional group is preferably a group other than a carboxyl group.

Among these, it is preferable that the said functional group is a hydroxyl group.

・Acrylic polymer (a11) having a functional group

Examples of the acrylic polymer (a11) having a functional group include those obtained by copolymerization of the acrylic monomer having the functional group and the acrylic monomer not having the functional group. Acrylic monomer) may be copolymerized.

Further, the acrylic polymer (a11) may be a random copolymer or a block copolymer, and a known method may be employed also for the polymerization method.

Examples of the acrylic monomer having a functional group include a hydroxyl group-containing monomer, a carboxyl group-containing monomer, an amino group-containing monomer, a substituted 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, and (meth)acrylate. )(Meth)acrylate hydroxyalkyl such as 2-hydroxybutyl acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; Non-(meth)acrylic unsaturated alcohols (unsaturated alcohols having no (meth)acryloyl skeleton), such as vinyl alcohol and allyl alcohol, may be mentioned.

Examples of the carboxy group-containing monomer include ethylenic unsaturation such as (meth)acrylic acid and crotonic acid.

Monocarboxylic acids (monocarboxylic acids having an ethylenically unsaturated bond); Ethylenically unsaturated dicarboxylic acids (dicarboxylic acids having an ethylenically unsaturated bond) such as fumaric acid, itaconic acid, maleic acid and citraconic acid; Anhydrides of the ethylenically unsaturated dicarboxylic acids; (Meth)acrylic acid carboxyalkyl esters, such as 2-carboxyethyl methacrylate, etc. are mentioned.

The acrylic monomer having the functional group is preferably a hydroxyl group-containing monomer.

The number of the acrylic monomers having the functional groups constituting the acrylic polymer (a11) may be only one type, or may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

Examples of acrylic monomers having no functional group include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, and (meth)acrylate. )Isobutyl acrylate, (meth)acrylic acid sec-butyl, (meth) acrylate tert-butyl, (meth) acrylate pentyl, (meth) acrylate, heptyl (meth) acrylate, (meth) acrylate 2-ethylhexyl, (meth) ) Isooctyl acrylate, (meth) acrylate n-octyl, (meth) acrylate n-nonyl, (meth) acrylate isononyl, (meth) acrylate, (meth) acrylate undecyl, (meth) acrylate dodecyl (( Meth) lauryl acrylate), (meth) tridecyl acrylate, (meth) tetradecyl acrylate ((meth) myristyl acrylate), pentadecyl (meth) acrylate, hexadecyl (meth) acrylate ((meth) palmityl acrylate) , (Meth)acrylic acid alkyl ester in which the alkyl group constituting the alkyl ester such as heptadecyl (meth)acrylate and octadecyl (meth)acrylate ((meth) acrylate stearyl) has a chain structure having 1 to 18 carbon atoms. have.

In addition, as an acrylic monomer having no functional group, for example, alkoxyalkyl groups such as methoxymethyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxymethyl (meth)acrylate, and ethoxyethyl (meth)acrylate Containing (meth)acrylic acid ester; (Meth)acrylic acid esters having an aromatic group including (meth)acrylate aryl esters such as phenyl (meth)acrylate; Non-crosslinkable (meth)acrylamide and derivatives thereof; And (meth)acrylic acid esters having non-crosslinkable tertiary amino groups such as N,N-dimethylaminoethyl (meth)acrylate and N,N-dimethylaminopropyl (meth)acrylate.

The acrylic monomers which do not have the functional groups constituting the acrylic polymer (a11) may be only one type, may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

Examples of the non-acrylic monomer include olefins such as ethylene and norbornene; Vinyl acetate; Styrene, etc. are mentioned.

The number of the non-acrylic monomers constituting the acrylic polymer (a11) may be only one type, or may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

In the acrylic polymer (a11), the ratio (content) of the amount of the structural unit derived from the acrylic monomer having the functional group to the total amount of the structural unit constituting it is preferably 0.1 to 50% by mass, and 1 to It is more preferable that it is 40 mass %, and it is especially preferable that it is 3-30 mass %. When the ratio is within such a range, in the acrylic resin (a1-1) obtained by copolymerization of the acrylic polymer (a11) and the energy ray-curable compound (a12), the content of the energy ray-curable group is the curing of the protective film. It becomes possible to easily adjust the degree of in a preferable range.

The number of the acrylic polymers (a11) constituting the acrylic resin (a1-1) may be one type, or may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

The ratio of the content of the acrylic resin (a1-1) to the total content of components other than the solvent in the composition (IV-1) (that is, the acrylic resin to the total mass of the film in the film for forming an energy ray-curable protective film ( The content ratio) of a1-1) is preferably 1 to 70% by mass, more preferably 5 to 60% by mass, and particularly preferably 10 to 50% by mass.

Energy ray-curable compound (a12)

The energy ray-curable compound (a12) preferably has one or two or more selected from the group consisting of an isocyanate group, an epoxy group and a carboxyl group as a group capable of reacting with a functional group of the acrylic polymer (a11), and as the group It is more preferable to have an isocyanate group. When the energy ray-curable compound (a12) has, for example, an isocyanate group as the group, the isocyanate group readily reacts with the hydroxyl group of the acrylic polymer (a11) having a hydroxyl group as the functional group.

The number of the energy ray-curable groups in one molecule of the energy ray-curable compound (a12) is not particularly limited, and may be appropriately selected in consideration of physical properties such as shrinkage required for the target protective film.

For example, the energy ray-curable compound (a12) preferably has 1 to 5 energy ray-curable groups per molecule, and more preferably has 1 to 3 energy ray-curable groups.

Examples of the energy ray-curable compound (a12) include 2-methacryloyloxyethyl isocyanate, meth-isopropenyl-α,α-dimethylbenzyl isocyanate, methacryloyl isocyanate, allyl isocyanate, and 1,1- (Bisacryloyloxymethyl) ethyl isocyanate;

An acryloyl monoisocyanate compound obtained by reaction of a diisocyanate compound or a polyisocyanate compound and hydroxyethyl (meth)acrylate;

And acryloyl monoisocyanate compounds obtained by reaction of a diisocyanate compound or a polyisocyanate compound, a polyol compound, and hydroxyethyl (meth)acrylate.

Among these, it is preferable that the said energy ray-curable compound (a12) is 2-methacryloyloxyethyl isocyanate.

The energy ray-curable compounds (a12) constituting the acrylic resin (a1-1) may be only one type, may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

The ratio of the content of the energy ray-curable group derived from the energy ray-curable compound (a12) to the content of the functional group derived from the acrylic polymer (a11) in the acrylic resin (a1-1) is 20 to 120 mol%. It is preferable that it is, and it is more preferable that it is 35-100 mol%, and it is especially preferable that it is 50-100 mol%. When the ratio of the content is within such a range, the adhesive strength of the cured product of the film for forming an energy ray-curable protective film becomes larger. On the other hand, in the case where the energy ray-curable compound (a12) is a monofunctional compound (having one group per molecule), the upper limit of the ratio of the content is 100 mol%, but the energy ray-curable compound (a12) is In the case of a polyfunctional (having two or more of the above groups per molecule), the upper limit of the ratio of the content may exceed 100 mol%.

The weight average molecular weight (Mw) of the polymer (a1) is preferably 100000 to 2000000, more preferably 300000 to 150,000.

Here, the "weight average molecular weight" is as previously described.

When the polymer (a1) is at least partially crosslinked by a crosslinking agent, the polymer (a1) does not correspond to any of the above-described monomers described as constituting the acrylic polymer (a11), and A monomer having a group reacting with a crosslinking agent may be polymerized and crosslinked in a group reacting with the crosslinking agent, or may be crosslinked in a group reacting with the functional group derived from the energy ray-curable compound (a12).

The polymer (a1) contained in the composition (IV-1) and the film for forming an energy ray-curable protective film may be one type or two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

(Compound (a2) having an energy ray-curable group and a molecular weight of 100 to 800,000)

Among the compounds (a2) having an energy ray-curable group having a molecular weight of 100 to 800,000, the energy ray-curable group includes a group containing an energy ray-curable double bond, and preferable examples include a (meth)acryloyl group and a vinyl group. Can be lifted.

The compound (a2) is not particularly limited as long as it satisfies the above conditions, and examples thereof include a low molecular weight compound having an energy ray-curable group, an epoxy resin having an energy ray-curable group, and a phenol resin having an energy ray-curable group.

Among the compounds (a2), examples of the low molecular weight compound having an energy ray-curable group include polyfunctional monomers or oligomers, and acrylate compounds having a (meth)acryloyl group are preferable.

Examples of the acrylate-based compound include 2-hydroxy-3-(meth)acryloyloxypropyl methacrylate, polyethylene glycol di(meth)acrylate, propoxylated ethoxylated bisphenol A di(meth) Acrylate, 2,2-bis[4-((meth)acryloxypolyethoxy)phenyl]propane, ethoxylated bisphenol A di(meth)acrylate, 2,2-bis[4-((meth)acryloxy Diethoxy)phenyl]propane, 9,9-bis[4-(2-(meth)acryloyloxyethoxy)phenyl]fluorene, 2,2-bis[4-((meth)acryloxypolypropoxy )Phenyl]propane, tricyclodecanedimethanoldi(meth)acrylate, 1,10-decanedioldi(meth)acrylate, 1,6-hexanedioldi(meth)acrylate, 1,9-nonanedioldi (Meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate, ethylene glycol di (Meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, 2,2-bis[4-((meth)acryloxyethoxy)phenyl]propane, neopentyl glycol Difunctional (meth)acrylates such as di(meth)acrylate, ethoxylated polypropylene glycol di(meth)acrylate, and 2-hydroxy-1,3-di(meth)acryloxypropane;

Tris(2-(meth)acryloxyethyl)isocyanurate, ε-caprolactone-modified tris(2-(meth)acryloxyethyl)isocyanurate, ethoxylated glycerin tri(meth)acrylate, pentaerythritol Tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, Polyfunctional (meth)acrylates such as dipentaerythritol poly(meth)acrylate and dipentaerythritol hexa(meth)acrylate;

Polyfunctional (meth)acrylate oligomers, such as a urethane (meth)acrylate oligomer, etc. are mentioned.

Among the compounds (a2), as an epoxy resin having an energy ray-curable group and a phenolic resin having an energy ray-curable group, those described in paragraph 0043 of “JP 2013-194102 A” can be used. These resins also correspond to resins constituting the thermosetting component described later, but are handled as the compound (a2) in the present invention.

It is preferable that it is 100-30000, and, as for the weight average molecular weight of the said compound (a2), it is more preferable that it is 300-10000.

The compound (a2) contained in the composition (IV-1) and the film for forming an energy ray-curable protective film may be only one type, may be two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

[Polymer (b) not having an energy ray-curable group]

When the composition (IV-1) and the film for forming an energy ray-curable protective film contain the compound (a2) as the energy ray-curable component (a), a polymer (b) having no energy ray-curable group is also contained. desirable.

The polymer (b) may be at least partially crosslinked with a crosslinking agent, or may not be crosslinked.

Examples of the polymer (b) having no energy ray-curable group include acrylic polymers, phenoxy resins, urethane resins, polyesters, rubber resins, and acrylic urethane resins.

Among these, the polymer (b) is preferably an acrylic polymer (hereinafter sometimes abbreviated as "acrylic polymer (b-1)").

The acrylic polymer (b-1) may be a known one, for example, a homopolymer of one acrylic monomer, a copolymer of two or more acrylic monomers, and one or two or more acrylic monomers and 1 It may be a copolymer of a type or a monomer other than two or more types of acrylic monomers (non-acrylic monomers).

Examples of the acrylic monomer constituting the acrylic polymer (b-1) include (meth)acrylate alkyl ester, (meth)acrylic acid ester having a cyclic skeleton, glycidyl group-containing (meth)acrylic acid ester, and hydroxyl group-containing ( Meth)acrylic acid ester, substituted amino group-containing (meth)acrylic acid ester, and the like. Here, the "substituted amino group" is as described above.

As the (meth)acrylate alkyl ester, for example, an acrylic monomer having no functional group constituting the acrylic polymer (a11) described above ((meth) in which the alkyl group constituting the alkyl ester has a chain structure having 1 to 18 carbon atoms. Acrylic acid alkyl ester, etc.) and the same can be mentioned.

Examples of the (meth)acrylate ester having a cyclic skeleton include (meth)acrylate cycloalkyl esters such as isobornyl (meth)acrylate and dicyclopentanyl (meth)acrylate;

(Meth)acrylic acid aralkyl esters such as benzyl (meth)acrylate;

(Meth) acrylate cycloalkenyl ester, such as (meth) acrylate dicyclopentenyl ester;

Cycloalkenyloxyalkyl (meth)acrylates, such as dicyclopentenyloxyethyl (meth)acrylate, etc. are mentioned.

Examples of the glycidyl group-containing (meth)acrylic acid ester include glycidyl (meth)acrylate.

Examples of the hydroxyl group-containing (meth)acrylic acid ester include hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 3-hydroxy (meth)acrylate. Propyl, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and the like.

Examples of the substituted amino group-containing (meth)acrylic acid ester include N-methylaminoethyl (meth)acrylate.

Examples of the non-acrylic monomer constituting the acrylic polymer (b-1) include olefins such as ethylene and norbornene; Vinyl acetate; Styrene, etc. are mentioned.

As the polymer (b) which does not have the energy ray-curable group at least partially cross-linked with a cross-linking agent, for example, a reactive functional group in the polymer (b) reacts with a cross-linking agent.

The reactive functional group may be appropriately selected depending on the type of crosslinking agent, and the like, and is not particularly limited. For example, when the crosslinking agent is a polyisocyanate compound, examples of the reactive functional group include a hydroxyl group, a carboxyl group, and an amino group, and among these, a hydroxyl group having high reactivity with an isocyanate group is preferable. Further, when the crosslinking agent is an epoxy-based compound, examples of the reactive functional group include a carboxyl group, an amino group, and an amide group, and among these, a carboxyl group having high reactivity with an epoxy group is preferable. However, it is preferable that the reactive functional group is a group other than a carboxyl group from the viewpoint of preventing corrosion of the circuit of the work or the workpiece.

Examples of the polymer (b) having no energy ray-curable group having a reactive functional group include those obtained by polymerizing at least a monomer having the reactive functional group. In the case of the acrylic polymer (b-1), as either or both of the above acrylic monomers and non-acrylic monomers used as monomers constituting it, what has the above reactive functional group may be used. Examples of the polymer (b) having a hydroxyl group as a reactive functional group include those obtained by polymerizing a hydroxyl group-containing (meth)acrylic acid ester. In addition, in the above acrylic monomer or non-acrylic monomer, one or two What is obtained by polymerizing a monomer obtained by substituting at least two hydrogen atoms with the above reactive functional groups is mentioned.

In the polymer (b) having a reactive functional group, the ratio (content) of the amount of the constituent unit derived from the monomer having the reactive functional group to the total amount of the constituent units constituting it is preferably 1 to 20% by mass, and 2 It is more preferable that it is -10 mass %. When the ratio is within such a range, the degree of crosslinking in the polymer (b) becomes a more preferable range.

The weight average molecular weight (Mw) of the polymer (b) not having an energy ray-curable group is preferably 10000 to 2000000, more preferably 100000 to 150,000, from the viewpoint of better film-forming properties of the composition (IV-1). . Here, the "weight average molecular weight" is as previously described.

The composition (IV-1) and the polymer (b) that does not have an energy ray-curable group contained in the film for forming an energy ray-curable protective film may be only one type, may be two or more types, and in the case of two or more types, the combination and ratio thereof may be arbitrarily selected. You can choose.

Examples of the composition (IV-1) include those containing either or both of the polymer (a1) and the compound (a2). In addition, when the composition (IV-1) contains the compound (a2), it is preferable that it further contains a polymer (b) that does not have an energy ray-curable group, and in this case, the composition (a1) further contains desirable. Further, the composition (IV-1) does not contain the compound (a2), and may contain the polymer (a1) and the polymer (b) having no energy ray-curable group together.

When the composition (IV-1) contains the polymer (a1), the compound (a2) and the polymer (b) not having an energy ray-curable group, the content of the compound (a2) in the composition (IV-1) is It is preferably 10 to 400 parts by mass, and more preferably 30 to 350 parts by mass, based on 100 parts by mass of the total content of the polymer (a1) and the polymer (b) having no energy ray-curable group.

The ratio of the total content of the energy ray-curable component (a) and the polymer (b) not having an energy ray-curable group to the total content of components other than the solvent in the composition (IV-1) (that is, the film for forming an energy ray-curable protective film The ratio of the total content of the energy ray-curable component (a) and the polymer (b) not having an energy ray-curable group) to the total mass of the film in is preferably 5 to 90% by mass, and 10 to 80% by mass It is more preferable that it is, and it is especially preferable that it is 20-70 mass %. Content of energy ray-curable component When the said ratio is such a range, the energy ray-curable property of the film for energy ray-curable protective film formation becomes more favorable.

In addition to the energy ray-curable component, the composition (IV-1) may contain one or two or more selected from the group consisting of a thermosetting component, a filler, a coupling agent, a crosslinking agent, a photopolymerization initiator, a colorant, and a general-purpose additive, depending on the purpose. do.

As the thermosetting component, filler, coupling agent, crosslinking agent, photopolymerization initiator, colorant and general-purpose additive in the composition (IV-1), the thermosetting component (B) and the filler (D) in the composition (III-1), respectively. , A coupling agent (E), a crosslinking agent (F), a photopolymerization initiator (H), a colorant (I), and the same as the general-purpose additive (J).

For example, the energy ray-curable protective film-forming film formed by using the composition (IV-1) containing the energy ray-curable component and the thermosetting component has improved adhesion to the adherend by heating, and this energy ray-curable The strength of the protective film formed from the film for forming a protective film is also improved.

In addition, the film for forming an energy ray-curable protective film formed by using the composition (IV-1) containing the energy ray-curable component and the colorant is the same as when the film for forming a thermosetting protective film described above contains the colorant (I). Expresses the effect.

In the composition (IV-1), the thermosetting component, filler, coupling agent, crosslinking agent, photopolymerization initiator, colorant and general-purpose additive may each be used singly or in combination of two or more, or two or more. When used together, their combination and ratio can be selected arbitrarily.

The content of the thermosetting component, coupling agent, crosslinking agent, photoinitiator, colorant and general-purpose additive in the composition (IV-1) may be appropriately adjusted according to the purpose, and is not particularly limited.

The content of the filler in the composition (IV-1) is preferably 80% by mass or less, preferably 70% by mass or less, and, for example, 50% by mass or more and 80% by mass or less, and 55% by mass or more and 80% by mass. Any of the following may be sufficient, and any of 50% by mass or more and 70% by mass or less, and 55% by mass or more and 70% by mass or less may be used. When the ratio is within such a range, it is possible to suppress mutual migration of components between the energy ray-curable pressure-sensitive adhesive and the protective film-forming film before energy ray curing.

The composition (IV-1) preferably further contains a solvent from the viewpoint of improving its handling properties by dilution.

The solvent contained in the composition (IV-1) includes, for example, the same solvent as the solvent in the composition (III-1).

The number of solvents contained in the composition (IV-1) may be one or two or more.

The content of the solvent in the composition (IV-1) is not particularly limited, and for example, it may be appropriately selected according to the kind of components other than the solvent.

<Method of manufacturing composition for energy ray-curable protective film formation>

A composition for forming an energy ray-curable protective film such as composition (IV-1) is obtained by blending each component for constituting it.

The composition for forming an energy ray-curable protective film can be produced in the same manner as in the case of the pressure-sensitive adhesive composition described above, except that the types of the blending components are different.

◎ Film for forming a non-curable protective film

As a preferable film for forming a non-curable protective film, those containing a thermoplastic resin and a filler are exemplified.

<Composition for forming a non-curable protective film (V-1)>

As a preferable composition for forming a non-curable protective film, for example, a composition for forming a non-curable protective film (V-1) containing the thermoplastic resin and a filler (in this specification, simply abbreviated as ``composition (V-1)''). There are cases), etc. are mentioned.

[Thermoplastic resin]

The thermoplastic resin is not particularly limited.

More specifically, as the thermoplastic resin, for example, not curable such as acrylic resin, polyester, polyurethane, phenoxy resin, polybutene, polybutadiene, polystyrene, etc. as contained components of the above-described composition (III-1) The same thing as resin can be mentioned.

The thermoplastic resins contained in the composition (V-1) and the film for forming a non-curable protective film may be one type or two or more types, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

The ratio of the content of the thermoplastic resin to the total content of components other than the solvent in the composition (V-1) (that is, the ratio of the thermoplastic resin to the total mass of the film for forming a non-curable protective film in the film for forming a non-curable protective film) The content ratio) is preferably 25 to 75% by mass.

[filling]

The film for forming a non-curable protective film containing a filler exhibits the same effects as the film for forming a thermosetting protective film containing the filler (D).

Examples of the filler contained in the composition (V-1) and the film for forming a non-curable protective film include the same fillers as the filler (D) contained in the composition (III-1) and the film for forming a thermosetting protective film.

The composition (V-1) and the non-curable protective film-forming film may contain only one type of filler, or two or more types of fillers, and in the case of two or more types, combinations and ratios thereof can be arbitrarily selected.

The ratio of the content of the filler to the total content of all components other than the solvent in the composition (V-1) (that is, the ratio of the content of the filler to the total mass of the film for forming a non-curable protective film in the film for forming a non-curable protective film) It is preferable that it is 50-75 mass %. When the ratio is within such a range, it becomes easier to adjust the coefficient of thermal expansion of the film for forming a non-curable protective film (that is, the protective film) as in the case of using the composition (III-1).

The composition (V-1) may contain other components depending on the purpose in addition to the thermoplastic resin and filler.

The other components are not particularly limited and may be arbitrarily selected according to the purpose.

For example, the film for forming a non-curable protective film (in other words, a protective film) formed by using the composition (V-1) containing the thermoplastic resin and the colorant, the film for forming a thermosetting protective film described above contains the colorant (I). It exhibits the same effect as in the case of doing so.

In the composition (V-1), the other components may be used alone or in combination of two or more, and when two or more are used in combination, combinations and ratios thereof can be arbitrarily selected.

The content of the other components of the composition (V-1) may be appropriately adjusted according to the purpose, and is not particularly limited.

The composition (V-1) preferably further contains a solvent from the viewpoint of improving its handling properties by dilution.

Examples of the solvent contained in the composition (V-1) include the same solvents as those in the above-described composition (III-1).

The number of solvents contained in the composition (V-1) may be one or two or more.

The content of the solvent in the composition (V-1) is not particularly limited, and for example, it may be appropriately selected according to the kind of components other than the solvent.

<Method of producing a composition for forming a non-curable protective film>

A composition for forming a non-curable protective film such as composition (V-1) is obtained by blending each component for constituting it.

The composition for forming a non-curable protective film can be prepared in the same manner as in the case of the pressure-sensitive adhesive composition described above, except that the types of the blending components are different.

In an embodiment of the composite sheet for forming a protective film, for example, a substrate is provided, and an energy ray-curable pressure-sensitive adhesive layer and a protective film-forming film are stacked in contact with each other in this order on one side of the substrate, and the The gel fraction of the pressure-sensitive adhesive layer is 80% or more, the glass transition temperature of the protective film-forming film is 3°C or more, the loss modulus at 23°C of the protective film-forming film is 3 MPa or more, and It is mentioned that the content ratio of the filler to the total mass is 40% by mass or more.

In addition, as an embodiment of the composite sheet for forming a protective film, for example, a substrate is provided, and on one side of the substrate, an energy ray-curable pressure-sensitive adhesive layer and a protective film are formed in contact with each other in this order, and are laminated, The gel fraction of the pressure-sensitive adhesive layer is 20% or more and less than 80%, the glass transition temperature of the protective film-forming film is 3°C or more, the protective film-forming film has a loss elastic modulus at 23°C of 3 MPa or more, and the protective film The ratio of the content of the filler to the total mass of the forming film is 40% by mass or more.

◇Method of manufacturing a composite sheet for forming a protective film

The above-described composite sheet for forming a protective film can be produced by laminating each of the above-described layers so as to have a corresponding positional relationship, and adjusting the shape of some or all of the layers as necessary. The method of forming each layer is as described above.

For example, when manufacturing a support sheet, in the case of laminating an adhesive layer on a substrate, the above-described adhesive composition may be coated on the substrate and dried as necessary.

In addition, the pressure-sensitive adhesive layer on the substrate is also applied by coating the pressure-sensitive adhesive composition on the release film and drying as necessary to form a pressure-sensitive adhesive layer on the release film, and bonding the exposed surface of the pressure-sensitive adhesive layer to one surface of the substrate. Can be stacked. At this time, it is preferable to apply the pressure-sensitive adhesive composition to the peeling-treated surface of the peeling film.

Until now, the case of laminating the pressure-sensitive adhesive layer on the substrate has been exemplified, but the above-described method can be applied, for example, even when laminating the other layer on the substrate.

On the other hand, for example, when a protective film-forming film is additionally laminated on the pressure-sensitive adhesive layer laminated on the substrate, it is possible to directly form the protective film-forming film by coating the protective film-forming composition on the pressure-sensitive adhesive layer. . Layers other than the film for forming a protective film can also be laminated on the pressure-sensitive adhesive layer by the same method using the composition for forming this layer. In this way, a new layer (hereinafter, abbreviated as the ``second layer'') is formed on any layer (hereinafter, abbreviated as the ``first layer'') stacked on the substrate, and a continuous two-layer stacked structure ( In other words, in the case of forming a laminated structure of the first layer and the second layer), a method of coating a composition for forming the second layer on the first layer and drying it as necessary may be applied. .

However, the second layer is formed in advance on the release film using the composition for forming it, and the exposed surface of the formed second layer on the side opposite to the side in contact with the release film is the exposed surface of the first layer. By bonding with, it is preferable to form a continuous two-layer laminated structure. At this time, it is preferable to apply the composition to the peeling-treated surface of the peeling film. The release film may be removed as necessary after formation of the laminated structure.

Here, the case of laminating the film for forming a protective film on the pressure-sensitive adhesive layer has been exemplified, but the target laminated structure can be arbitrarily selected, for example, the case of laminating the other layer on the pressure-sensitive adhesive layer.

In this way, all layers other than the base material constituting the composite sheet for forming a protective film can be formed in advance on the release film and laminated by a method of bonding them to the surface of the target layer. Therefore, such a process is employed as necessary. The layer to be formed may be appropriately selected to produce a protective film-forming composite sheet.

On the other hand, the composite sheet for forming a protective film is usually stored in a state in which a release film is adhered to the surface of the outermost layer (for example, a film for forming a protective film) on the opposite side of the supporting sheet. Therefore, a composition for forming a layer constituting an outermost layer, such as a composition for forming a protective film, is applied on this release film (preferably, the peeling treatment surface thereof) and, if necessary, dried to form the outermost layer on the release film. By forming a layer constituting the layer, and laminating the remaining layers on the exposed surface of the side opposite to the side in contact with the release film of this layer by any of the above-described methods, and leaving the release film in a bonded state without removing the , A composite sheet for forming a protective film on which a release film was formed is obtained.

◇Method of manufacturing a workpiece with a protective film (how to use a composite sheet for forming a protective film)

The composite sheet for forming a protective film can be used for manufacturing a workpiece on which the protective film is formed.

As an example of a method for manufacturing a work product in which a protective film having a protective film is formed at any part of the work product, the protective film forming film in the protective film-forming composite sheet is attached to a target location of the work, so that the protective film is applied to the work. An affixing step for producing a laminate on which the forming composite sheet was formed (laminated), a curing step for curing the protective film forming film performed as necessary after the attaching step, and the above in the laminated body after the attaching step The protective film-forming film or its cured product is printed on the protective film-forming film or its cured product by irradiating the protective film-forming film or its cured product from the outside on the support sheet side of the protective film-forming composite sheet and beyond the support sheet. It has a printing process for performing the printing process and a processing process for producing a work product by processing the work after the printing process, and the film for forming a protective film after being affixed to the work is not cured, but a protective film obtained by curing or A manufacturing method in which the cargo is used as a protective film is mentioned.

When the work is a semiconductor wafer, an example of a method for manufacturing a work product with a protective film, that is, a semiconductor chip with a protective film, is a method for manufacturing a semiconductor chip in which a protective film with a protective film is formed on the back surface of the semiconductor chip, wherein the protective film is formed. An affixing step of fabricating a laminate in which the protective film-forming composite sheet is formed on the back surface of the semiconductor wafer by attaching a protective film-forming film in the semiconductor wafer to the back surface of the semiconductor wafer, and the protective film performed as necessary after the attaching step. After a curing step of curing the film for formation and the attaching step, the outer side of the supporting sheet side of the composite sheet for forming a protective film with respect to the film for forming a protective film or a cured product thereof in the composite sheet for forming a protective film in the laminate. A printing process in which printing is performed on the film for forming a protective film or a cured product thereof by irradiating a laser light over the supporting sheet from and by dividing the semiconductor wafer after the printing process to produce a semiconductor chip, and further forming the protective film. A dividing/cutting process for cutting the film or a cured product thereof, and a pickup process for separating and picking up the semiconductor chip provided with the cut film for forming a protective film or the cured product from the support sheet, and to the semiconductor wafer A manufacturing method in which the film for forming a protective film after sticking is not cured is used as a protective film, or a cured product obtained by curing is used as a protective film.

In the above manufacturing method, when the work is a semiconductor wafer, the work described above can be used.

In the above manufacturing method, by using the composite sheet for forming a protective film according to the present embodiment described above, even when the laser light having a short wavelength such as 266 nm is irradiated, the film for forming a protective film in the composite sheet for forming a protective film or the same The cured product can be printed satisfactorily. Moreover, this printing can be visually recognized well beyond the support sheet from the outside on the support sheet side of the composite sheet for forming a protective film.

The manufacturing method is a manufacturing method in the case of having the curing step (in this specification, it may be referred to as ``manufacturing method (1)''), and a manufacturing method in the case of not having the curing step (in this specification, `` It can be divided into a manufacturing method (2)").

Hereinafter, these manufacturing methods are sequentially described.

<<Manufacturing method (1)>>

The manufacturing method (1) is a method for manufacturing a workpiece in which a protective film having a protective film is formed at any location of the workpiece, and the protective film-forming film in the protective film-forming composite sheet is adhered to a target location of the workpiece. An affixing step of producing a laminate in which the composite sheet for forming a protective film is formed (laminated) on a work, a curing step of curing the protective film-forming film after the attaching step, and the above in the laminated body after the attaching step The protective film-forming film or its cured product is printed on the protective film-forming film or its cured product by irradiating the protective film-forming film or its cured product from the outside on the support sheet side of the protective film-forming composite sheet and beyond the support sheet. The cured product obtained by curing the film for forming a protective film after being affixed to the work is used as a protective film, having a printing step for performing a printing step and a processing step for producing a work product by processing the work after the printing step.

3 is a cross-sectional view schematically illustrating an example of the manufacturing method 1 when the work is a semiconductor wafer. Here, a manufacturing method in the case where the composite sheet 101 for forming a protective film shown in Fig. 1 is used will be described.

<Adhesion process>

In the affixing step, the protective film-forming composite sheet 101 from which the release film 15 was removed is used, and as shown in Fig. 3A, the protective film-forming film 13 in the protective film-forming composite sheet 101 is used as a semiconductor. It is affixed to the back surface 9b of the wafer 9. Thereby, the laminated body 901 comprised with the semiconductor wafer 9 and the composite sheet 101 for protective film formation formed on its back surface 9b is manufactured.

In the affixing step, the protective film-forming film 13 may be heated to soften it and adhere to the semiconductor wafer 9.

On the other hand, here, the illustration of bumps on the circuit formation surface 9a in the semiconductor wafer 9 is omitted.

In addition, reference numeral 13b denotes a surface of the side opposite to the first surface 13a of the protective film-forming film 13 (that is, the pressure-sensitive adhesive layer 12 side) (in this specification, it may be referred to as a ``second surface'') There is).

In order to make the thickness of the semiconductor wafer 9 a target value, the back surface of the semiconductor wafer 9 may be ground. That is, the back surface 9b of the semiconductor wafer 9 may be a grinding surface.

In the semiconductor wafer 9, it is preferable that there is no groove penetrating between the circuit formation surface 9a and the back surface 9b.

<hardening process>

In the curing step after the attaching step, the protective film-forming film 13 is cured as shown in Fig. 3B.

Here, the case of performing a curing process before the said printing process is shown.

In the present embodiment, the cured product obtained by curing the film 13 for forming a protective film after affixing to the semiconductor wafer 9 is used as a protective film regardless of the presence or absence of the cut.

By performing the curing step, the protective film-forming composite sheet 101 becomes the protective film-forming composite sheet 1011 in which the protective film-forming film 13 became the cured product 13', and the semiconductor wafer 9 and the A cured laminate 9011 constructed with the composite sheet 1011 for forming a protective film formed on the back surface 9b is obtained.

Reference numeral 13a' denotes the first surface of the cured product 13' corresponding to the first surface 13a of the protective film-forming film 13, and reference numeral 13b' denotes the second surface of the protective film-forming film 13 The second surface of the cured product 13' corresponding to (13b) is shown.

In the curing step, when the protective film-forming film 13 is thermosetting, the protective film-forming film 13 is heated to form a cured product 13'. When the protective film-forming film 13 is energy ray-curable, the cured product 13' is formed by irradiating the protective film-forming film 13 with energy rays through the support sheet 10.

In the curing step, the curing conditions of the protective film-forming film 13, that is, the heating temperature and heating time during thermal curing, and the illuminance and light amount of the energy rays during energy ray curing are as described above.

<Printing process>

After the affixing step, in the printing step, as shown in Fig. 3C, a composite sheet for forming a protective film with respect to the cured product 13' in the composite sheet 1011 for forming a protective film in the cured laminate 9011 Printing is performed on the cured product 13' by irradiating the laser light L over the support sheet 10 from the outside on the support sheet 10 side of (1011). Printing (not shown) is applied to the second surface 13b' of the cured product 13'.

By performing the printing process, the protective film-forming composite sheet 1011 becomes a protective film-forming composite sheet 1012 provided with the printed cured product 13', and the semiconductor wafer 9 and its back surface 9b are A printed and cured laminate 9012 constructed with the installed protective film-forming composite sheet 1012 is obtained.

The wavelength of the laser light L is preferably shorter than the conventional one, and more preferably 266 nm.

<Segmentation/cutting process>

After the printing step, in the dividing/cutting step, as shown in Fig. 3D, the semiconductor wafer 9 is divided to produce a semiconductor chip 9', and the cured product 13' is further cut.

A semiconductor chip 91 on which a protective film constituted by performing the dividing/cutting process, comprising the semiconductor chip 9 ′ and the cured product 130 ′ after cutting formed on the rear surface 9b ′ of the semiconductor chip 9 ′ A plurality of these are obtained. The semiconductor chips 91 on which the plurality of protective films are formed are all aligned on one support sheet 10, and the semiconductor chip 91 and the support sheet 10 on which these protective films are formed are semiconductors with a protective film formed thereon. It constitutes a chip group 910.

Reference numeral 130a' denotes the first surface of the cured product 130' after cutting corresponding to the first surface 13a' of the cured product 13', and reference numeral 130b' denotes the first surface of the cured product 13'. A second surface of the cured product 130 ′ after cutting corresponding to the second surface 13b ′ is shown.

Reference numeral 9a' denotes a circuit formation surface of the semiconductor chip 9'corresponding to the circuit formation surface 9a of the semiconductor wafer 9.

Fabrication of the semiconductor chip 9'by dividing the semiconductor wafer 9 (in other words, into pieces) can be performed by a known method.

The method of dividing the semiconductor wafer 9 includes, for example, blade dicing in which the semiconductor wafer 9 is diced using a blade; Laser dicing for dicing the semiconductor wafer 9 by laser irradiation; A method of cutting a semiconductor wafer such as water dicing in which the semiconductor wafer 9 is diced by spraying water containing an abrasive may be mentioned. The cutout may be up to the pressure-sensitive adhesive layer 12 or may reach the base material 11. In the case of up to the pressure-sensitive adhesive layer 12, it becomes difficult to generate a cutting mark. In the case of the base material 11, the expandability at the time of expansion is improved.

In the case of applying these methods, for example, by dividing the semiconductor wafer 9 and cutting the cured product 13 ′ at the same time, the division of the semiconductor wafer 9 and the cured product 13 ′ You may cut it collectively.

As a method of dividing the semiconductor wafer 9, a method other than a method of cutting the semiconductor wafer may be mentioned.

That is, in this method, first, a portion to be divided in the semiconductor wafer 9 is set, and a modified layer is formed inside the semiconductor wafer 9 by irradiating laser light so as to focus on this point as a focal point. To form. Unlike other places on the semiconductor wafer, the modified layer of the semiconductor wafer is deteriorated by irradiation of laser light, and the intensity is weakened. For this reason, when a force is applied to the semiconductor wafer 9, cracks extending in both directions of the semiconductor wafer 9 in the modified layer inside the semiconductor wafer 9 occur, and the semiconductor wafer 9 is divided. It is the starting point of (cutting). Next, a force is applied to the semiconductor wafer 9, and the semiconductor wafer 9 is divided at the portion of the modified layer to fabricate a semiconductor chip. A method of dividing the semiconductor wafer 9 accompanying the formation of such a modified layer is called stealth dicing (registered trademark).

For example, a semiconductor wafer on which a modified layer is formed can be divided by expanding it in a direction parallel to its surface and applying a force. In this way, when the method of expanding the semiconductor wafer is applied, the cured product 13' of the protective film forming film is expanded together with the semiconductor wafer 9, and the cured product 13' is also cut at the same time. By doing so, the division of the semiconductor wafer 9 and the cutting of the cured product 13' may be performed collectively. The cutting of the cured product 13' by expansion is preferably performed under a low temperature such as -20 to 5°C.

In the case where the division of the semiconductor wafer 9 and the cutting of the cured product 13 ′ are not collectively performed, in addition to the division of the semiconductor wafer 9, the cured product 13 ′ is separately cut by a known method. do.

<Pick-up process>

After the dividing/cutting step, in the pick-up step, as shown in Fig. 3E, a semiconductor chip 9 ′ (a semiconductor chip 91 with a protective film formed thereon) having the cured product 130 ′ after cutting is provided as a supporting sheet. Separate from (10) and pick up. Here, the direction of the pickup is indicated by arrow I.

The semiconductor chip 91 on which the protective film is formed can be picked up by a known method. For example, as the separating means 8 for separating the semiconductor chip 91 on which the protective film is formed from the support sheet 10, a vacuum collet or the like may be mentioned. On the other hand, here, only the separating means 8 is not displayed in cross section, and this is the same in the following drawings.

By the above, the semiconductor chip 91 on which the target protective film was formed is obtained.

In the semiconductor chip 91 on which the protective film, which is the object of the printing process including the pick-up, is formed, printing is clearly maintained on the second surface 130B' of the cured product 130' after cutting.

<Timing to perform the curing process>

Up to this point, the case where the curing step is performed between the affixing step and the printing step has been described, but in the manufacturing method (1), the timing at which the curing step is performed is not limited thereto. For example, in the manufacturing method (1), the curing process may be performed in any one between the printing process and the division/cutting process, between the division/cutting process and the pickup process, and after the pickup process.

In the case of performing the curing step after the affixing step and the printing step, in the printing step, for the protective film forming film 13 in the composite sheet 101 for forming a protective film in the laminate 901 shown in Fig. 3A, for forming a protective film Printing is performed on the protective film forming film 13 by irradiating the laser light L over the support sheet 10 from the outside on the support sheet 10 side of the composite sheet 101. Printing (not shown) is applied to the second surface 13b of the protective film-forming film 13.

The printing process in this case, except that the irradiation target of the laser light L is not the cured product 13' of the protective film 13, but the film 13 for forming a protective film, It can be done in the same way as in the case.

<Other process>

The manufacturing method (1) may have other steps that do not correspond to any of these in addition to the respective steps of the affixing step, the curing step, the printing step, the dividing/cutting step, and the pickup step.

The types of the other processes and the timing for performing them can be arbitrarily selected according to the purpose and are not particularly limited.

<<Manufacturing method (2)>>

The manufacturing method (2) is a method for manufacturing a workpiece in which a protective film having a protective film is formed at any location of the workpiece, and the protective film-forming film in the protective film-forming composite sheet is attached to a target location of the workpiece. For forming the protective film for the film for forming a protective film in the composite sheet for forming the protective film in the laminated body after the attaching step for producing a laminate in which the composite sheet for forming a protective film was formed on a work (laminated), and after the attaching step It has a printing process of printing the film for forming a protective film by irradiating laser light from the outside on the support sheet side of the composite sheet to the support sheet, and a processing process of producing a workpiece by processing the work after the printing process. And a manufacturing method of forming a protective film without curing the film for forming a protective film after being affixed to the work.

The manufacturing method (2) is the same as the manufacturing method (1), except that the above-described curing step is not provided regardless of the type of work, and the film for forming a protective film after affixed to the work is used as a protective film, and the manufacturing method ( It has the same effect as in the case of 1).

Up to this point, a method for manufacturing a work product with a protective film formed in the case of using the composite sheet 101 for forming a protective film shown in Fig. 1 has been mainly described, but the method for producing a work product with a protective film in this embodiment is not limited thereto. .

For example, even if a material other than the protective film-forming composite sheet 101 shown in FIG. 1 is used, such as the protective film-forming composite sheet shown in FIG. 2, a workpiece with a protective film formed in the same manner can be produced by the above-described manufacturing method. I can.

In the case of using the composite sheet for forming a protective film of another embodiment, based on the difference in the structure between the sheet and the composite sheet for forming a protective film 101, appropriately add, change, or delete steps in the above-described manufacturing method. May be carried out to produce a workpiece with a protective film formed thereon.

◇Method of manufacturing semiconductor devices

After obtaining a work product with a protective film formed thereon by the above-described manufacturing method, a semiconductor device can be manufactured by a known suitable method depending on the type of the work product with the protective film formed thereon. For example, if the workpiece on which the protective film is formed is a semiconductor chip on which the protective film is formed, the semiconductor chip on which the protective film is formed is flip-chip connected to the circuit surface of the substrate, and then a semiconductor package is formed, and the semiconductor package is used for the purpose. It is possible to manufacture a semiconductor device (not shown).

Example

Hereinafter, the present invention will be described in more detail by specific examples. However, the present invention is not limited to the examples shown below at all.

<Materials for manufacturing resin>

The official names of raw materials for producing resins abbreviated in the present Examples and Comparative Examples are shown below.

MA: methyl acrylate

HEA: 2-hydroxyethyl acrylate

2EHA: acrylate-2-ethylhexyl

MOI: 2-methacryloyloxyethyl isocyanate

BA: n-butyl acrylate

GMA: Glycidyl methacrylate

VAc: Vinyl acetate

AA：acrylic acid

HEMA: 2-hydroxyethyl methacrylate

<Materials for manufacturing the composition for forming a protective film>

The raw materials used for production of the composition for forming a protective film are shown below.

[Polymer component (A)]

(A)-1: Acrylic polymer obtained by copolymerizing MA (85 parts by mass) and HEA (15 parts by mass) (weight average molecular weight 300000, glass transition temperature 6°C)

(A)-2: Acrylic polymer obtained by copolymerizing BA (55 parts by mass), MA (10 parts by mass), GMA (20 parts by mass) and HEA (15 parts by mass) (weight average molecular weight 800000, glass transition temperature -28) ℃)

[Thermosetting component (B1)]

(B1)-1: Bisphenol A type epoxy resin (Mitsubishi Chemical Co., Ltd. "jER828", epoxy equivalent 184 to 194 g/eq)

(B1)-2: Bisphenol A type epoxy resin (Mitsubishi Chemical Co., Ltd. "jER1055", epoxy equivalent 800 to 900 g/eq)

(B1)-3: Dicyclopentadiene type epoxy resin ("Epiclo HP-7200HH" manufactured by DIC Corporation, epoxy equivalent 255 to 260 g/eq)

[Thermal Curing Agent (B2)]

(B2)-1: Dicyandiamide, a thermally active latent epoxy resin curing agent (manufactured by Mitsubishi Chemical Corporation, DICY7, active hydrogen content: 21 g/eq)

[Hardening accelerator (C)]

(C)-1: 2-phenyl-4,5-dihydroxymethylimidazole (Shikoku Chemical Industry Co., Ltd. "Qazole 2PHZ-PW")

[Filling material (D)]

(D)-1: Silica filler (melted quartz filler, average particle diameter 8 µm)

[Coupling agent (E)]

(E)-1: Silane coupling agent (Shin-Etsu Chemical Industries, Ltd., KBM503)

[Crosslinking agent (F)]

(F)-1: Isocyanate crosslinking agent ("Coronate L" manufactured by Tosoh Corporation, tolylene diisocyanate trimer adduct of trimethylolpropane)

[Coloring agent (I)]

(I)-1: 32 parts by mass of a phthalocyanine-based blue pigment (Pigment Blue 15:3), 18 parts by mass of an isoindolinone-based yellow pigment (Pigment Yellow 139), and 50 parts by mass of an anthraquinone-based red pigment (Pigment Red 177) A pigment obtained by mixing parts and making the pigment so that the total amount of the three dyes/the amount of styrene acrylic resin = 1/3 (mass ratio).

[Energy ray curable resin (G)]

(G)-1: ε-caprolactone-modified tris (2-acryloxyethyl) isocyanurate (Shin-Nakamura Chemical Co., Ltd. "A-9300-1CL", trifunctional ultraviolet curable compound)

[Example 1]

<<Manufacture of supporting sheet>>

<Production of adhesive resin (I-2a)>

2EHA (42 parts by mass), VAc (40 parts by mass), and a copolymer of HEA (18 parts by mass) to an acrylic polymer having a weight average molecular weight of 600000 in MOI (with respect to the total number of moles of hydroxyl groups derived from HEA in the acrylic polymer) An amount of 0.8 times the total number of isocyanate groups) was added, and an addition reaction was carried out at 50°C for 48 hours in an air stream to obtain the target adhesive resin (I-2a)-1.

Hereinafter, the said acrylic polymer may be called "adhesive resin (I-1a)-1".

<Preparation of adhesive composition (I-2)>

Adhesive resin (I-2a)-1 (100 parts by mass), hexamethylene diisocyanate-based crosslinking agent ("Coronate L" manufactured by Tosoh Corporation) (0.21 parts by mass) and a photoinitiator ("Irgacure 127" manufactured by BASF Corporation), Contains 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]-phenyl}-2-methyl-propan-1-one) (3 parts by mass) Further, ethyl acetate was contained as a solvent, and an energy ray-curable pressure-sensitive adhesive composition (I-2)-1 was prepared in which the total concentration of all components other than the solvent was 30% by mass. On the other hand, the content of components other than ethyl acetate shown here is the content of a target substance which does not contain a solvent.

<Manufacture of support sheet>

A release film ("SP-PET381031" manufactured by Lintec, 38 µm in thickness), in which one side of the polyethylene terephthalate film was peeled off by silicone treatment, was used, and the pressure-sensitive adhesive composition (I-2) obtained above was used on the release-treated side. )-1 was applied and heated and dried at 100° C. for 2 minutes to form an energy ray-curable pressure-sensitive adhesive layer having a thickness of 5 μm. The gel fraction of the pressure-sensitive adhesive layer was 90%. On the other hand, the gel fraction of the pressure-sensitive adhesive layer is a measured value by the method described above. This is also the same in the following Examples and Comparative Examples.

Next, by bonding a polypropylene film 1 (thickness 80 μm, colorless) as a base material on the exposed surface of the pressure-sensitive adhesive layer, the base material, the pressure-sensitive adhesive layer, and the release film are laminated in this order in their thickness direction. A laminated sheet, that is, a supporting sheet on which a release film was formed, was prepared.

<<Production of protective film formation film>>

<Preparation of protective film-forming composition (III-1)>

Polymer component (A)-1 (25.5 parts by mass), thermosetting component (B1)-1 (10.2 parts by mass), (B1)-2 (1.7 parts by mass), (B1)-3 (5.4 parts by mass), thermosetting agent (B2)-1 (0.4 parts by mass), curing accelerator (C)-1 (0.4 parts by mass), filler (D)-1 (54.1 parts by mass), coupling agent (E)-1 (0.3 parts by mass), and colorant (I)-1 (2.0 parts by mass) is dissolved or dispersed in a mixed solvent of methyl ethyl ketone, toluene and ethyl acetate and stirred at 23°C to form a thermosetting protective film in which the total concentration of all components other than the solvent is 50% by mass Composition (III-1)-1 was obtained. On the other hand, the blending amounts of components other than the mixed solvent shown here are all blending amounts of the target substance not containing a solvent.

The content of the filler in the composition for forming a thermosetting protective film excluding the solvent was 54.1% by mass. In addition, Tg of the composition for forming a protective film was 23.5°C.

<Production of film for protective film formation>

Using a release film (2nd release film, "SP-PET381031" manufactured by Lintec, 38 µm in thickness), in which one side of a polyethylene terephthalate film was peeled off by silicone treatment, the protective film obtained above was formed on the release treated side. The composition (III-1)-1 was coated and dried at 100° C. for 2 minutes to prepare a film for forming a thermosetting protective film having a thickness of 25 μm.

The loss modulus E" of the film for forming a protective film was 51.6 MPa.

Moreover, by bonding the peeling-treated surface of the peeling film (the 1st peeling film, "SP-PET381031" by Lintec Co., Ltd. 38 micrometers in thickness) to the exposed surface of the obtained protective film formation film on the side which does not have a 2nd peeling film, A laminated film comprising a protective film-forming film, a first release film formed on one surface of the protective film-forming film, and a second release film formed on the other surface of the protective film-forming film was obtained.

<<Production of composite sheet for protective film formation>>

The release film was removed from the support sheet obtained above. Moreover, the 1st peeling film was removed from the laminated film obtained above. And, by bonding the exposed surface of the pressure-sensitive adhesive layer formed by removing the release film and the exposed surface of the protective film-forming film formed by removing the first release film, the substrate, the pressure-sensitive adhesive layer, the protective film-forming film, and the second release film In this order, a composite sheet for forming a protective film formed by being laminated in these thickness directions was produced.

<<Evaluation of composite sheet for protective film formation>>

Using the composite sheet for forming a protective film, an 8-inch mirror wafer and a film for forming a protective film were bonded together. The laminated body of the obtained wafer and the composite sheet for forming a protective film was heated at 130° C. for 2 hours to cure the film for forming a protective film to form a protective film, and then left to stand at room temperature.

Thereafter, the wafer surface was adsorbed and fixed to the suction table, the end of the support sheet was held with an arm, and a peel test at the interface between the protective film and the support sheet was performed at a peel angle of 180° and a peel rate (300 mm/min). According to the standard, the peelability of the protective film and the supporting sheet to the interface was evaluated.

A: It was able to peel without a problem at the interface between a protective film and a support sheet.

B: Although peeling was possible at the interface between the protective film and the supporting sheet, there was a jam (zipping) at the time of peeling.

C: The interface between the wafer and the protective film failed to peel off at the interface between the protective film and the support sheet.

<<Production and evaluation of protective film-forming film and protective film-forming composite sheet>>

[Example 2]

In the preparation of the composition for forming a protective film, a film and a protective film for forming a protective film in the same manner as in Example 1, except that 29.6 parts by mass of the polymer component (A)-1 and 50 parts by mass of the filler (D)-1 were used. A composite sheet for formation was prepared and evaluated.

The loss modulus E" of the film for forming a protective film was 11.0 MPa.

The content of the filler in the composition for forming a thermosetting protective film excluding the solvent was 50.0% by mass. In addition, Tg of the composition for forming a protective film was 13.0°C.

Table 1 shows the results.

[Example 3]

In the preparation of the composition for forming a protective film, except that the polymer component (A)-2 (19.0 parts by mass) is used instead of the polymer component (A)-1 (25.5 parts by mass) and 60.6 parts by mass of the filler (D)-1 is used. , In the same manner as in Example 1, a support sheet, a film for forming a protective film, and a composite sheet for forming a protective film were prepared and evaluated.

The loss modulus E" of the film for forming a protective film was 2.2 MPa.

The content of the filler in the composition for forming a thermosetting protective film excluding the solvent was 60.6% by mass. In addition, Tg of the composition for forming a protective film was 2.2°C.

Table 1 shows the results.

[Example 4]

In the preparation of the composition for forming a protective film, except that the polymer component (A)-2 (25.5 parts by mass) is used instead of the polymer component (A)-1 (25.5 parts by mass) and 54.1 parts by mass of the filler (D)-1 is used. , In the same manner as in Example 1, a protective film-forming film and a protective film-forming composite sheet were prepared and evaluated.

The loss modulus E" of the film for forming a protective film was 1.3 MPa.

The content of the filler in the composition for forming a thermosetting protective film excluding the solvent was 54.1% by mass. In addition, Tg of the composition for forming a protective film was 1.7°C.

Table 1 shows the results.

[Example 5]

Polymer component (A)-1 (35.98 parts by mass), thermosetting component (B1)-1 (11.24 parts by mass), (B1)-2 (2.04 parts by mass), (B1)-3 (7.48 parts by mass), thermosetting agent (B2)-1 (0.48 parts by mass), curing accelerator (C)-1 (0.48 parts by mass), filler (D)-1 (40.0 parts by mass), coupling agent (E)-1 (0.3 parts by mass), and colorant (I)-1 (2.0 parts by mass) is dissolved or dispersed in a mixed solvent of methyl ethyl ketone, toluene and ethyl acetate and stirred at 23°C to form a thermosetting protective film in which the total concentration of all components other than the solvent is 50% by mass Composition (III-1)-1 was obtained. On the other hand, the blending amounts of components other than the mixed solvent shown here are all blending amounts of the target substance not containing a solvent.

The content of the filler in the composition for forming a thermosetting protective film excluding the solvent was 40.0% by mass. In addition, Tg of the composition for forming a protective film was 16.5°C.

Next, using the composition for forming a protective film, a film for forming a protective film and a composite sheet for forming a protective film were prepared and evaluated in the same manner as in Example 1.

The loss modulus E" of the film for forming a protective film was 18.4 MPa.

Table 1 shows the results.

[Example 6]

In the production of the supporting sheet, the energy ray-curable adhesive composition (I-2)-2 prepared by the method shown below was used instead of the energy ray-curable adhesive composition (I-2)-1, and the thickness of the adhesive layer was 5 A support sheet, a film for forming a protective film, and a composite sheet for forming a protective film were produced and evaluated in the same manner as in Example 1, except that it was set to 10 µm instead of µm. The gel fraction of the pressure-sensitive adhesive layer was 50%. In addition, the loss modulus E" of the film for forming a protective film was 51.6 MPa.

Table 1 shows the results.

<Production of adhesive resin (I-2a)>

2EHA (21 parts by mass), VAc (76 parts by mass), AA (1 parts by mass), and HEMA (2 parts by mass) acrylic polymer (100 parts by mass) having a weight average molecular weight of 300000, bifunctional and hexafunctional Urethane acrylate mixture (72 parts by mass), hexamethylene diisocyanate-based crosslinking agent ("Coronate L" manufactured by Tosoh Corporation) (3 parts by mass), photoinitiator ("Irgacure 127" manufactured by BASF Corporation), 2-hydroxy- 1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]-phenyl}-2-methyl-propan-1-one) (3 parts by mass) was mixed with ethyl acetate. By making the concentration 30%, the target adhesive resin (I-2a)-2 was obtained.

<Preparation of adhesive composition (I-2)-2>

Adhesive resin (I-2a)-2 (100 parts by mass), hexamethylene diisocyanate-based crosslinking agent ("Coronate L" manufactured by Tosoh Corporation) (3 parts by mass) and a photoinitiator ("Irgacure 127" manufactured by BASF Corporation), Contains 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]-phenyl}-2-methyl-propan-1-one) (3 parts by mass) Then, ethyl acetate was further contained as a solvent, and the energy ray-curable adhesive composition (I-2)-2 was prepared in which the total concentration of all components other than the solvent was 30% by mass. On the other hand, the contents of components other than ethyl acetate shown here are all contents of the target substance not containing a solvent.

The content of the filler in the composition for forming a thermosetting protective film excluding the solvent was 54.1% by mass. In addition, Tg of the composition for forming a protective film was 23.5°C.

Table 1 shows the results.

[Example 7]

In the preparation of the composition for forming a protective film, a film for forming a protective film and a protective film were formed in the same manner as in Example 6, except that 29.6 parts by mass of the polymer component (A)-1 and 50 parts by mass of the filler (D)-1 were used. The composite sheet for use was prepared and evaluated.

The loss modulus E" of the film for forming a protective film was 11.0 MPa.

The content of the filler in the composition for forming a thermosetting protective film excluding the solvent was 50.0% by mass. In addition, Tg of the composition for forming a protective film was 13.0°C.

Table 1 shows the results.

[Example 8]

In the production of the supporting sheet, a protective film-forming film and a protective film in the same manner as in Example 5, except that the pressure-sensitive adhesive composition (I-2)-2 was used instead of the energy ray-curable pressure-sensitive adhesive composition (I-2)-1. A composite sheet for formation was prepared and evaluated.

The loss modulus E" of the film for forming a protective film was 18.4 MPa.

The content of the filler in the composition for forming a thermosetting protective film excluding the solvent was 40.0% by mass. In addition, Tg of the composition for forming a protective film was 16.5°C.

Table 1 shows the results.

[Example 9]

<Preparation of the composition for forming a protective film (IV-1)>

Polymer component (A)-1 (27.07 parts by mass), energy ray-curable resin (G)-1 (10.0 parts by mass), crosslinking agent (F)-1 (0.77 parts by mass), photoinitiator ((``Irga Cure 369", 2-(dimethylamino)-1-(4-morpholinophenyl)-2-benzyl-1-butanone) (0.6 parts by mass), filler (D)-1 (56.65 parts by mass), couple By dissolving or dispersing the ring agent (E)-1 (0.4 parts by mass) and the coloring agent (I)-1 (4.5 parts by mass) in a mixed solvent of methyl ethyl ketone, toluene and ethyl acetate and stirring at 23°C, An energy ray-curable protective film-forming composition (III-1)-1 having a total concentration of the components of 50% by mass was obtained. .

The content of the filler in the composition for forming an energy ray-curable protective film excluding the solvent was 56.7% by mass. In addition, Tg of the composition for forming a protective film was 6.2°C.

<Production of film for protective film formation>

Using a release film (2nd release film, "SP-PET381031" manufactured by Lintec, 38 µm in thickness) in which one side of a polyethylene terephthalate film was peeled off by silicone treatment, the obtained protective film was formed on the release treated side. The composition (III-1)-1 was coated and dried at 100° C. for 2 minutes to prepare a film for forming an energy ray-curable protective film having a thickness of 25 μm.

The loss modulus E" of the film for forming a protective film was 5.8 MPa.

Moreover, by bonding the peeling-treated surface of the peeling film (the 1st peeling film, "SP-PET381031" by Lintec Co., Ltd. 38 micrometers in thickness) to the exposed surface of the obtained protective film formation film on the side which does not have a 2nd peeling film, A laminated film comprising a protective film-forming film, a first release film formed on one surface of the protective film-forming film, and a second release film formed on the other surface of the protective film-forming film was obtained.

<<Production of composite sheet for protective film formation>>

The release film was removed from the support sheet obtained in the same manner as in Example 1. Moreover, the 1st peeling film was removed from the laminated film obtained above. And, by bonding the exposed surface of the pressure-sensitive adhesive layer formed by removing the release film and the exposed surface of the protective film-forming film formed by removing the first release film, the substrate, the pressure-sensitive adhesive layer, the protective film-forming film, and the second release film In this order, a composite sheet for forming a protective film formed by being laminated in these thickness directions was produced.

Then, instead of curing by heating at 130°C for 2 hours, a protective film was formed in the same manner as in Example 1, except that light having a wavelength of 365 nm was irradiated three times under conditions of illuminance 215 mJ/cm 2 and light amount 187 mJ/cm 2 to cure. The dragon composite sheet was evaluated.

Table 1 shows the results.

[Comparative Example 1]

In the preparation of the composition for forming a protective film, except that the polymer component (A)-2 (19.0 parts by mass) is used instead of the polymer component (A)-1 (25.5 parts by mass) and 60.6 parts by mass of the filler (D)-1 is used. In the same manner as in the case of Example 6, a protective film-forming film and a protective film-forming composite sheet were produced and evaluated.

The loss modulus E" of the film for forming a protective film was 2.2 MPa.

The content of the filler in the composition for forming a thermosetting protective film excluding the solvent was 60.6% by mass. In addition, Tg of the composition for forming a protective film was 2.2°C.

Table 1 shows the results.

[Comparative Example 2]

In the preparation of the composition for forming a protective film, except that the polymer component (A)-2 (25.5 parts by mass) is used instead of the polymer component (A)-1 (25.5 parts by mass) and 54.1 parts by mass of the filler (D)-1 is used. In the same manner as in the case of Example 6, a protective film-forming film and a protective film-forming composite sheet were prepared and evaluated.

The loss modulus E" of the film for forming a protective film was 1.3 MPa.

The content of the filler in the composition for forming a thermosetting protective film excluding the solvent was 54.1% by mass. In addition, Tg of the composition for forming a protective film was 1.7°C.

Table 1 shows the results.

As apparent from the above results, in Examples 1 to 5 and 9, the gel fraction of the pressure-sensitive adhesive of the support sheet before UV curing was 90%, the peelability evaluation of the composite sheet for forming a protective film was A, and the support sheet and the protective film It could be gently peeled off at the interface of the forming film.

In Examples 6 to 8, the gel fraction of the pressure-sensitive adhesive of the supporting sheet before UV curing was 50%, but the Tg of the protective film-forming film was 3°C or higher, and the peelability evaluation of the protective film-forming composite sheet was A or B. . In Example 8, the peeling evaluation was slightly poor, but in any composite sheet for forming a protective film, it could be peeled at the interface between the support sheet and the film for forming a protective film.

In contrast, in both the composite sheets for forming a protective film of Comparative Examples 1 and 2, the gel fraction of the pressure-sensitive adhesive of the supporting sheet before UV curing was 50%, and the Tg of the film for forming a protective film was less than 3°C. In addition, the loss elastic modulus E" at 23°C of the protective film-forming film was less than 3 MPa. As a result, the peelability evaluation of the protective film-forming composite sheet was C, and it could not be peeled off at the interface between the support sheet and the protective film-forming film , It peeled off at the interface between the film for protective film formation and an adherend.

The present invention can be used in the manufacture of a semiconductor device.

101, 102... Composite sheet for forming a protective film, 1011... Composite sheet for forming a protective film in which a film for forming a protective film is cured, 1012... Composite sheet for forming a protective film in which a film for forming a protective film is cured and printed, 10... Support sheet, 10a... One side (first side) of the support sheet, 13, 23... Film for forming a protective film, 13'... Protective film (cured product of film for forming a protective film), 130'... Protective film after cutting (cured product of film for forming a protective film after cutting), 9... Semiconductor wafer, 9a... Circuit formation surface of semiconductor wafer, 9b... The back side of the semiconductor wafer, 9'... Semiconductor chip, L... Laser light

Claims (5)

A substrate is provided, and an energy ray-curable pressure-sensitive adhesive layer and a film for forming a protective film are stacked in contact with each other in this order on one side of the substrate,
The composite sheet for forming a protective film in which the gel fraction of the pressure-sensitive adhesive layer is 80% or more. A substrate is provided, and an energy ray-curable pressure-sensitive adhesive layer and a protective film-forming film are laminated on one side of the substrate in contact with each other in this order
As the gel fraction of the pressure-sensitive adhesive layer is 20% or more and less than 80%,
A composite sheet for forming a protective film having a glass transition temperature of 3° C. or higher of the film for forming a protective film. The method of claim 1,
A composite sheet for forming a protective film having a glass transition temperature of 3° C. or higher of the film for forming a protective film. The method according to any one of claims 1 to 3,
The composite sheet for forming a protective film, wherein the protective film-forming film has a loss modulus of 3 MPa or more at 23°C. The method according to any one of claims 1 to 4,
The protective film-forming film contains a filler (D),
In the protective film-forming film, the content ratio of the filler (D) to the total mass of the protective film-forming film is 50% by mass or more.

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