JP2021037624A - Composite sheet for forming protective film - Google Patents

Abstract

To provide a composite sheet for forming a protective film that can suppress components of an energy line curable adhesive moving to a film for forming a protective film before energy line curing, and can peel a semiconductor chip with a protective film from a support sheet without peeling between the semiconductor chip and the protective film when picking up the semiconductor chip with the protective film from the support sheet.SOLUTION: A composite sheet for forming a protective film comprises a substrate, wherein an energy line curable adhesive layer and a film for forming a protective film are laminated in contact with each other in this order on one surface of the substrate, a gel fraction of the adhesive layer is 80% or more, or the gel fraction of the adhesive layer is 20% or more and lower than 80%, and a glass transition temperature of the film for forming the protective film is 3°C or more.SELECTED DRAWING: None

Description

The present invention relates to a composite sheet for forming a protective film.

In the manufacturing process of a semiconductor device, a work that needs to be processed to obtain a target object may be protected by a protective film.
For example, at the time of 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 the circuit surface is used as a work, and is a semiconductor wafer or a divided product thereof. In a semiconductor chip, in order to suppress the occurrence of cracks, the back surface of the semiconductor wafer or the semiconductor chip opposite to the circuit surface may be protected by a protective film. Further, in the manufacturing process of a semiconductor device, a semiconductor device panel described later is used as a work, and in order to suppress the occurrence of warpage or cracks in this panel, any part of the panel may be protected by a protective film.

In order to form such a protective film, for example, a support sheet is provided, and a protective film forming film for forming the protective film is further provided on one surface of the support sheet. A composite sheet for forming is used.
The protective film-forming film may function as a protective film by its curing, or may function as a protective film in an uncured state. Further, the support sheet can be used for fixing a work provided with a protective film forming film or a cured product thereof. For example, when a semiconductor wafer is used as the work, the support sheet can be used as a dicing sheet required when the semiconductor wafer is divided into semiconductor chips. Examples of the support sheet include a base material and a pressure-sensitive adhesive layer provided on one surface of the base material; a base material only. When the support sheet includes the pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer is arranged between the base material and the protective film-forming film in the protective film-forming composite sheet.

When the above-mentioned composite sheet for forming a protective film is used, first, the film for forming a protective film in the composite sheet for forming a protective film is attached to a target portion of the work.
Next, in the work provided with such a composite sheet for forming a protective film, a work piece is obtained by performing processing as necessary. For example, when a semiconductor wafer is used as the work, after the protective film-forming composite sheet is attached to the back surface of the work by the protective film-forming film therein, the protective film-forming film is formed at appropriate timings. A semiconductor chip having a protective film forming film or protective film on the back surface, cutting the protective film forming film or protective film, dividing the semiconductor wafer into semiconductor chips (dying), and forming the protective film or protective film after cutting. The semiconductor chip with a protective film forming film or the semiconductor chip with a protective film) is appropriately picked up from the support sheet. When a semiconductor chip with a protective film forming film is picked up, the semiconductor chip with a protective film forming film is made into a semiconductor chip with a protective film by curing the protective film forming film, and finally the semiconductor chip with a protective film is formed. Is used to manufacture semiconductor devices.

Patent Document 1 describes a flip chip formed by a thermosetting resin component and a thermoplastic resin component having a glass transition temperature of 25 ° C. or higher and 200 ° C. or lower on a dicing tape in which an adhesive is laminated on a base material. A dicing tape-integrated semiconductor back surface film on which a mold semiconductor back surface film is laminated is disclosed.

Japanese Patent No. 5479991

As such a composite sheet for forming a protective film, in addition to a support sheet provided with an adhesive layer that is cured by heating, a support sheet provided with an adhesive layer that is cured by irradiation with energy rays such as ultraviolet rays is available. It's being used.
The energy ray-curable pressure-sensitive adhesive is usually composed of a photopolymerizable resin and a photopolymerization initiator, and when irradiated with energy rays, the photopolymerizable resin is crosslinked by the photopolymerization initiator and cured. Before linear curing, the non-crosslinked photopolymerizable resin and photopolymerization initiator are transferred from the pressure-sensitive adhesive layer to the protective film-forming film, and the components of the protective film-forming film are transferred to the pressure-sensitive adhesive layer. There is a problem of doing. When such a transfer of components occurs, the pressure-sensitive adhesive layer after irradiation with energy rays is insufficiently cured, or crosslinks occur between the pressure-sensitive adhesive layer and the protective film-forming film, resulting in cured protection. When a semiconductor chip having a film on the back surface (semiconductor chip with a protective film) is picked up from the support sheet, the semiconductor chip with the protective film cannot be peeled off from the support sheet, and the semiconductor chip and the protective film are peeled off. there is a possibility.

The present invention comprises a base material, and an energy ray-curable pressure-sensitive adhesive layer and a protective film-forming film are laminated in this order on one surface of the base material in contact with each other, and a semiconductor chip with a protective film is laminated. It is an object of the present invention to provide a composite sheet for forming a protective film capable of peeling a semiconductor chip with a protective film from the support sheet without peeling between the semiconductor chip and the protective film when picking up the semiconductor chip from the support sheet. And.

The present invention comprises a base material, and an energy ray-curable pressure-sensitive adhesive layer and a protective film-forming film are laminated in this order on one surface of the base material in contact with each other. Provided is a composite sheet for forming a protective film having a gel content of 80% or more.
The present invention comprises a base material, and an energy ray-curable pressure-sensitive adhesive layer and a protective film-forming film are laminated in this order on one surface of the base material in contact with each other. Provided is a protective film-forming composite sheet having a gel content of 20% or more and less than 80% and a glass transition temperature (Tg) of the protective film-forming film of 3 ° C. or higher.

The protective film-forming composite sheet of the present invention preferably has a loss elastic modulus of 3 MPa or more at 23 ° C. of the protective film-forming film.
In the protective film-forming composite sheet of the present invention, the protective film-forming film contains a filler (D), and the filler (D) in the protective film-forming film with respect to the total mass of the protective film-forming film. The ratio of the content of D) is preferably 50% by mass or more.

According to the present invention, a semiconductor chip with a protective film is provided, and an energy ray-curable pressure-sensitive adhesive layer and a protective film-forming film are laminated in this order on one surface of the base material in contact with each other. Provided is a composite sheet for forming a protective film capable of peeling a semiconductor chip with a protective film from the support sheet without peeling between the semiconductor chip and the protective film when the semiconductor chip is picked up from the support sheet.

It is sectional drawing which shows typically an example of the composite sheet for forming a protective film which concerns on one Embodiment of this invention. It is sectional drawing which shows typically another example of the composite sheet for forming a protective film which concerns on one Embodiment of this invention. It is sectional drawing for schematically explaining an example of the manufacturing method of the semiconductor chip with a protective film when the composite sheet for forming a protective film which concerns on one Embodiment of this invention is used.

Protective Film Forming Composite Sheet The protective film forming composite sheet according to the first embodiment of the present invention includes a base material, and forms an energy ray-curable pressure-sensitive adhesive layer and a protective film on one surface of the base material. The films for use are laminated in this order in contact with each other, and the gel fraction of the pressure-sensitive adhesive layer is 80% or more.
By setting the gel fraction of the energy ray-curable pressure-sensitive adhesive in the pressure-sensitive adhesive layer of the protective film-forming composite sheet to the lower limit value or more, the energy ray-curable pressure-sensitive adhesive layer before energy ray-curing and the protective film It is possible to suppress the mutual transfer of components between the forming film and the protective film, and when the semiconductor chip with the protective film is picked up from the support sheet, the components do not peel off between the semiconductor chip and the protective film. The semiconductor chip with a protective film can be peeled off from the support sheet.

The composite sheet for forming a protective film according to the second embodiment of the present invention includes a base material, and an energy ray-curable pressure-sensitive adhesive layer and a film for forming a protective film are placed on one surface of the base material in this order. The pressure-sensitive adhesive layer is laminated in contact with each other, the gel content of the pressure-sensitive adhesive 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%, the energy before energy ray curing It is possible to prevent the components from migrating to each other between the linear curable pressure-sensitive adhesive layer and the protective film-forming film, and when picking up the protective film-equipped semiconductor chip from the support sheet, it protects the semiconductor chip. The semiconductor chip with a protective film can be peeled off from the support sheet without peeling off from the film.

In the protective film forming composite sheet of the present invention, the loss elastic modulus E ″ of the protective film forming film at 23 ° C. is preferably 3 MPa or more, more preferably 5 MPa or more, and 10 MPa or more. Is more preferable, and for example, it may be either 17 MPa or more and 45 MPa or more. When the loss elastic modulus of the protective film forming film at 23 ° C. is equal to or higher than the lower limit value, the protective film of low molecular weight components such as the photopolymerizable resin of the energy ray-curable pressure-sensitive adhesive and the photopolymerizable initiator. It is possible to suppress the transition to the forming film.

The loss elastic modulus E ″ of the protective film forming film at 23 ° C. is preferably 100 MPa or less, more preferably 90 MPa or less. When the loss elastic modulus E ″ of the protective film forming film at 23 ° C. is not more than the lower limit value, the handleability of the protective film forming film attached to the work can be improved.

In the protective film-forming composite sheet of the present invention, the protective film-forming film contains a filler (D), and in the protective film-forming film, the filler (with respect to the total mass of the protective film-forming film). The ratio of the content of D) is preferably 50% by mass or more, more preferably 53% by mass or more, further preferably 55% by mass or more, for example, even 60% by mass. Good. When the ratio of the content of the filler (D) to the total mass of the protective film forming film in the protective film forming film is equal to or more than the lower limit value, the light of the energy ray-curable pressure-sensitive adhesive is obtained. It is possible to further suppress the transfer of low molecular weight components such as a polymerizable resin and a photopolymerizable initiator to a protective film-forming film.

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, more preferably 80% by mass or less. When the ratio of the content of the filler (D) to the total mass of the protective film forming film in the protective film forming film is not more than the lower limit value, the protective film forming film can be added to the work. The stickability is improved.

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

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

Further, in the present specification, the description of "adhesive layer" simply means "adhesive layer before curing".

The composite sheet for forming a protective film of the present embodiment does not fall under any of the base material, the pressure-sensitive adhesive layer, the film for forming a protective film, and the release film, as long as the effects of the present invention are not impaired. It may have a layer of.
The type of the other layer is not particularly limited and can be arbitrarily selected depending on the intended purpose.
The arrangement position, shape, size, etc. of the other layers can be arbitrarily selected according to the type thereof, and are not particularly limited, but the size of the protective film forming film is preferably larger than that of the work.

The thickness of the work to which the composite sheet for forming the protective film of the present embodiment is attached is not particularly limited, but is 30 to 1000 μm in that processing (for example, division) into a work piece to be described later becomes easier. It is preferably 70 to 400 μm, and more preferably 70 to 400 μm.

The composite sheet for forming a protective film of the present embodiment is for sticking to a work, and a preferred work to be stuck is, for example, a semiconductor wafer. The composite sheet for forming a protective film is preferably used for sticking to the back surface of a semiconductor wafer.

FIG. 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 provided on the support sheet 10 and one surface of the support sheet 10 (sometimes referred to as a "first surface" in the present specification) 10a. It is configured to include a forming film 13.
The support sheet 10 includes a base material 11 and an adhesive layer 12 provided on one surface 11a of the base material 11. In the protective film forming composite sheet 101, the pressure-sensitive adhesive layer 12 is arranged between the base material 11 and the protective film forming film 13.
That is, the protective film-forming composite sheet 101 is configured by laminating the base material 11, the pressure-sensitive adhesive layer 12, and the protective film-forming film 13 in this order in the thickness direction.
The surface (sometimes referred to as the "first surface" in the present specification) 10a of the support sheet 10 on the protective film forming film 13 side is the surface of the pressure-sensitive adhesive layer 12 opposite to the base material 11 side (the surface is opposite to the base material 11 side). In this specification, it is the same as 12a) (sometimes referred to as "first surface").

The protective film-forming composite sheet 101 further includes a jig adhesive layer 16 and a release film 15 on the protective film-forming film 13.
In the protective film forming composite sheet 101, the protective film forming film 13 is laminated on the entire surface or almost the entire surface of the first surface 12a of the adhesive layer 12, and is different from the adhesive layer 12 side of the protective film forming film 13. The adhesive layer 16 for jigs is laminated on a part of the opposite surface (sometimes referred to as the "first surface" in the present specification) 13a, that is, in a region near the peripheral edge portion. Further, in the first surface 13a of the protective film forming film 13, the region where the jig adhesive layer 16 is not laminated and the side opposite to the protective film forming film 13 side of the jig adhesive layer 16. The release film 15 is laminated on the surface (sometimes referred to as the "first surface" in the present specification) 16a.

Not limited to the case of the protective film forming composite sheet 101, in the protective film forming composite sheet of the present embodiment, the release film (for example, the release film 15 shown in FIG. 1) has an arbitrary configuration, and the present embodiment has an arbitrary configuration. The composite sheet for forming a protective film may or may not include 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 adhesive layer 16 for jigs may have, for example, a single-layer structure containing an adhesive component, or a plurality of layers in which layers containing an adhesive component are laminated on both sides of a sheet serving as a core material. It may have a structure.

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

FIG. 2 is a cross-sectional view schematically showing another example of the composite sheet for forming a protective film according to an embodiment of the present invention.
In the drawings after FIG. 2, the same components as those shown in the already explained figures are designated by the same reference numerals as in the case of the already explained figures, and detailed description 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 adhesive layer for jigs is not the first surface of the protective film-forming film but the first adhesive layer. It is the same as the protective film forming composite sheet 101 shown in FIG. 1 except that it is laminated on the surface.

More specifically, in the protective film forming composite sheet 102, the protective film forming film 23 is a part of a region of the first surface 12a of the pressure-sensitive adhesive layer 12, that is, the width direction of the pressure-sensitive adhesive layer 12 (FIG. 2). It is laminated in the region on the central side in the left-right direction). Further, the jig adhesive layer 16 is laminated on the first surface 12a of the pressure-sensitive adhesive layer 12 in the region where the protective film forming film 23 is not laminated, that is, in the region near the peripheral edge portion. Then, the surface of the protective film forming film 23 opposite to the adhesive layer 12 side (sometimes referred to as the "first surface" in the present specification) 23a and the jig adhesive layer 16 are the first. The release film 15 is laminated on one surface 16a.

Up to this point, as for the protective film forming composite sheet provided with the adhesive layer for jigs, the protective film forming composite sheet 101 shown in FIG. 1 and the protective film forming composite sheet 102 shown in FIG. 2 are shown. However, this is an example of another composite sheet for forming a protective film provided with an adhesive layer for jigs.

A protective film forming composite sheet provided with such a jig adhesive layer is used by attaching the first surface of the jig adhesive layer to a jig such as a ring frame.
As described above, the protective film-forming composite sheet of the present embodiment may be provided with an adhesive layer for jigs regardless of the form of the support sheet and the protective film-forming film.

Examples of the protective film-forming composite sheet without the jig adhesive layer include the protective film-forming composite sheet 102 shown in FIG. 2 which does not have the jig adhesive layer 16. However, this is an example of another composite sheet for forming a protective film that does not have an adhesive layer for jigs.

In FIGS. 1 and 2, the base material, the pressure-sensitive adhesive layer, the protective film-forming film and the release film are shown as constituting the protective film-forming composite sheet, but the protective film-forming composite of the present embodiment is shown. The sheet may include the other layers that do not fall under any of these.
When the protective film-forming composite sheet shown in FIGS. 1 and 2 includes the other layer, the arrangement position thereof is not particularly limited except between the pressure-sensitive adhesive layer and the protective film-forming 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 the protective film will be described in detail.

◇ Support Sheet The support sheet according to the embodiment of the present invention can form a protective film-forming composite sheet by laminating it with a protective film-forming film, for example, as will be described later.

The support sheet of the present embodiment can be used to fix a work provided with a protective film forming film or a cured product thereof, which will be described later, at any position.
Examples of the work include semiconductor wafers, semiconductor device panels, and the like. The semiconductor device panel is handled in the manufacturing process of the semiconductor device, and a specific example thereof includes a semiconductor device panel in which a plurality of electronic components are mounted on one circuit board.
In the present specification, a processed work is referred to as a "work processed product". For example, when the work is a semiconductor wafer, the workpiece may be a semiconductor chip.
For example, when the work is a semiconductor wafer, the support sheet of the present embodiment can be used to fix a semiconductor wafer having a protective film forming film or a cured product thereof on the back surface.

Examples of the support sheet include a base material and a pressure-sensitive adhesive layer provided on one surface of the base material. When the support sheet includes the pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer is arranged between the base material and the protective film-forming film in the protective film-forming composite sheet described later.

When a support sheet provided with a base material and an adhesive layer is used, the adhesive strength or adhesiveness between the support sheet and the protective film-forming film can be easily adjusted in the protective film-forming composite sheet.
When a support 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 support sheet provided with a base material and an adhesive layer is used, it is possible to impart a new function to the support sheet or the composite sheet for forming a protective film. In addition, the adhesive strength or adhesiveness between the support sheet and the protective film forming film can be adjusted more easily than in the case of the above-mentioned pressure-sensitive adhesive layer.

◎ Base material The base material is in the form of a sheet or a film, and examples of the constituent material of the base material 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); polyethylene terephthalate (PET), polyethylene naphthalate ( PEN), polyesters such as polybutylene terephthalate (PBT); polyether sulfone, polyacrylic acid ester; polycarbonate (PC) and the like.

The resin constituting the base material may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected.

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

In the present specification, not only in the case of a base material, "a plurality of layers may be the same or different from each other" means "all layers may be the same or all layers are different". It may mean that only some of the layers may be the same, and further, "multiple 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". means.

The thickness of the base material is preferably 50 to 300 μm, more preferably 60 to 140 μm, and particularly preferably 80 to 100 μm. When the thickness of the base material is within such a range, the flexibility of the composite sheet for forming the protective film and the adhesiveness to the work or the work-processed material are further improved.
Here, the "thickness of the base material" means the thickness of the entire base material, and for example, the thickness of the base material composed of a plurality of layers means the total thickness of all the layers constituting the base material. means.

It is preferable that the base material has a high accuracy of thickness, that is, a base material in which variation in thickness is suppressed regardless of the site. Among the above-mentioned constituent materials, examples of the materials that can be used to construct such a highly accurate base material with a thickness include polyolefin, polyethylene terephthalate, and the like.

In addition to the main constituent materials such as the resin, the base material contains various known additives such as fillers, colorants, antistatic agents, antioxidants, organic lubricants, catalysts, and softeners (plasticizers). You may.

The base material 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 vapor-deposited. May be good.
For example, when the protective film forming film has energy ray curability, the base material preferably transmits energy rays.
For example, in order to optically inspect the protective film-forming film in the protective film-forming composite sheet via the base material, the base material is preferably transparent.

In order to improve the adhesion of the base material to the layer provided on it (for example, adhesive layer, protective film forming film, etc.), the base material is subjected to sandblasting treatment, solvent treatment, or other unevenness treatment; corona discharge treatment, electrons. The surface may be subjected to an oxidation treatment such as a line irradiation treatment, a plasma treatment, an ozone / ultraviolet irradiation treatment, a flame treatment, a chromic acid treatment, or a hot air treatment. Further, the surface of the base material may be primed.
In addition, the base material prevents the base material from adhering to other sheets and the base material from adhering to the adsorption table when the antistatic coat layer; the composite sheet for forming the protective film is laminated and stored. It may have a layer or the like.

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

◎ Adhesive layer The adhesive layer is in the form of a sheet or a film and contains an adhesive.
Examples of the pressure-sensitive adhesive include adhesive resins such as acrylic resin, urethane resin, rubber resin, silicone resin, epoxy resin, polyvinyl ether, polycarbonate, and ester resin, and acrylic resin is preferable. ..

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 having adhesiveness, but also a resin that exhibits adhesiveness when used in combination with other components such as additives, and adhesiveness due to the presence of a trigger such as heat or water. Also included are resins and the like.

The pressure-sensitive adhesive layer may be composed of one layer (single layer), may be composed 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. The combination of these plurality of layers is not particularly limited.

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 at least the above lower limit value, the effect of providing the pressure-sensitive adhesive layer can be obtained more remarkably. When the thickness of the pressure-sensitive adhesive layer is not more than the upper limit value, printing can be performed better on the protective film-forming film or the cured product thereof in the protective film-forming composite sheet. Then, this printing can be better visually recognized from the outside of the protective film forming composite sheet on the support sheet side through the support sheet.
Here, the "thickness of the pressure-sensitive 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 is the sum of all the layers constituting the pressure-sensitive adhesive layer. Means the thickness of.

In the present embodiment, the pressure-sensitive adhesive layer is formed by 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 the physical properties before and after curing. For example, these semiconductor chips can be more easily picked up by curing the energy ray-curable pressure-sensitive adhesive layer before picking up the semiconductor chip with a protective film or the semiconductor chip with a film for forming a protective film, which will be described later.

In the present specification, the "energy beam" means an electromagnetic wave or a charged particle beam having an energy quantum, and examples thereof include ultraviolet rays, radiation, and electron beams. Ultraviolet rays can be irradiated by using, for example, a high-pressure mercury lamp, a fusion lamp, a xenon lamp, a black light, an LED lamp, or the like as an ultraviolet source. The electron beam can be irradiated with an electron beam generated by an electron beam accelerator or the like.
Further, in the present specification, "energy ray curable" means a property of being cured by irradiating with energy rays, and "non-energy ray curable" is a property of not being cured by irradiating with energy rays. Means.

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 content of the pressure-sensitive adhesive layer is 80% or more, the components are suppressed from being transferred to each other between the energy ray-curable pressure-sensitive adhesive layer before energy ray curing and the protective film forming film. When the semiconductor chip with the protective film is picked up from the support sheet, the semiconductor chip with the protective film can be peeled off 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 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 content of the pressure-sensitive adhesive layer is less than 80%, the energy ray-curable adhesive before the energy ray-curing is due to the glass transition temperature (Tg) of the protective film forming film described later being 3 ° C. or higher. It is possible to prevent the components from migrating to each other between the agent layer and the protective film forming film, and when the protective film-equipped semiconductor chip is picked up from the support sheet, it is between the semiconductor chip and the protective film. It is possible to peel off the semiconductor chip with the protective film from the support sheet without peeling off with.
In the composite sheet for forming a protective film of the second embodiment, when the gel fraction of the pressure-sensitive adhesive layer is within the above range, the pressure-sensitive adhesive layer can be easily formed. When the gel fraction is less than 20%, the pressure-sensitive adhesive layer remains on the protective film-forming film, and the reliability of the semiconductor chip with the protective film is lowered.

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 having a silicone-based release agent layer formed on one surface of a polyethylene terephthalate base film (thickness 38 μm) is prepared. Next, the pressure-sensitive adhesive composition is applied to the peel-treated surface of the release film and dried to form a pressure-sensitive adhesive layer having a thickness of 20 μm.
Next, this pressure-sensitive adhesive layer is cut into a size of 50 mm × 100 mm to obtain a sample, and the sample is wrapped in a nylon mesh sheet (mesh size 200) having a size of 100 mm × 150 mm to obtain a test piece. The mass M1 of the sample only is weighed with a precision balance, then the test piece is immersed in ethyl acetate (100 mL) at 25 ° C. for 24 hours, the test piece is taken out, dried at 120 ° C. for 1 hour, and further 23 ° C. , The humidity is adjusted by leaving it for 1 hour under the condition of 50% relative humidity. Next, the mass M2 of the sample only, excluding the mass of the mesh sheet of the test piece, is weighed with a precision balance. Then, the gel fraction before the energy ray irradiation of the sample (that is, the pressure-sensitive adhesive layer) is calculated by the following formula.
Gel fraction of adhesive layer (%) = (M2 / M1) x 100

<< Adhesive composition >>
The pressure-sensitive adhesive layer can be formed by using a pressure-sensitive adhesive composition containing a pressure-sensitive adhesive. For example, the pressure-sensitive adhesive layer can be formed on a target portion by applying the pressure-sensitive adhesive composition to the surface to be formed of the pressure-sensitive adhesive layer and drying it if necessary. The ratio of the contents of the components that do not vaporize at room temperature in the pressure-sensitive adhesive composition is usually the same as the ratio of the contents of the components in the pressure-sensitive adhesive layer. In the present specification, "room temperature" means a temperature that is not particularly cooled or heated, that is, a normal temperature, and examples thereof include a temperature of 15 to 25 ° C.

The pressure-sensitive adhesive composition may be applied 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, and a screen coater. , A method using various coaters such as a Meyer bar coater and a knife coater.

The drying conditions of the pressure-sensitive adhesive composition are not particularly limited. When the pressure-sensitive adhesive composition contains a solvent described later, it is preferably heat-dried. The solvent-containing pressure-sensitive adhesive composition is preferably dried at 70 to 130 ° C. for 10 seconds to 5 minutes, for example.

When the pressure-sensitive adhesive layer is provided on the base material, for example, the pressure-sensitive adhesive layer may be laminated on the base material by applying the pressure-sensitive adhesive composition on the base material and drying it if necessary. When the pressure-sensitive adhesive layer is provided on the base material, for example, the pressure-sensitive adhesive composition is applied onto the release film and dried as necessary to form the pressure-sensitive adhesive layer on the release film. The pressure-sensitive adhesive layer may be laminated on the base material by adhering the exposed surface of the pressure-sensitive adhesive layer to one surface of the base material. In this case, the release film may be removed at any timing of the manufacturing process or the use process of the protective film forming composite sheet.

In the present invention, the pressure-sensitive adhesive is energy ray-curable. Examples of the energy ray-curable pressure-sensitive adhesive composition include a non-energy ray-curable pressure-sensitive adhesive resin (I-1a) (hereinafter, may be abbreviated as "sticky resin (I-1a)"). Adhesive composition (I-1) containing an energy ray-curable compound and an energy ray-curable adhesive resin (I-1) in which an unsaturated group is introduced into the side chain of the adhesive resin (I-1a). -2a) (hereinafter, may be abbreviated as "adhesive resin (I-2a)")-containing adhesive composition (I-2); the adhesive resin (I-2a) and energy ray curing. Examples thereof include a pressure-sensitive adhesive composition (I-3) containing a sex compound.

[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 collectively referred to as "the pressure-sensitive adhesive composition (I)". The adhesive resin (I-1a) in (abbreviated as -1) to (I-3) ") is preferably an acrylic resin.

Examples of the acrylic resin include acrylic polymers having at least a structural unit derived from (meth) acrylic acid alkyl ester.
Examples of the (meth) acrylic acid alkyl ester include those in which the alkyl group constituting the alkyl ester has 1 to 20 carbon atoms, and the alkyl group is linear or branched. Is preferable.

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 that includes both "acryloyl group" and "methacryloyl group", and "(meth) acrylate". Is a concept that includes both "acrylate" and "methacrylate".

The acrylic polymer preferably has a structural unit derived from a functional group-containing monomer in addition to the structural unit derived from the (meth) acrylic acid alkyl ester.
As the functional group-containing monomer, for example, the functional group may be a starting point of cross-linking by reacting with a cross-linking agent described later, or the functional group may react with an unsaturated group in an unsaturated group-containing compound described later. Then, there is one that enables the introduction of an unsaturated group into the side chain of the acrylic polymer.

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

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

In the pressure-sensitive adhesive compositions (I-1) to (I-3), the structural unit of the acrylic resin such as the acrylic polymer may be only one type, two or more types, or two or more types. If, the combination and ratio thereof can be arbitrarily selected.

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

The pressure-sensitive adhesive composition (I-1) or the pressure-sensitive adhesive resin (I-1a) contained in the pressure-sensitive adhesive composition (I-3) may be only one type, two or more types, or two or more types. If so, their combinations and ratios can be arbitrarily selected.

In the pressure-sensitive adhesive composition (I-1), the ratio of the content of the pressure-sensitive adhesive resin (I-1a) to the total mass of the pressure-sensitive 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) is, for example, energy ray-polymerizable unsaturated with functional groups in the pressure-sensitive adhesive resin (I-1a). It is obtained by reacting an unsaturated group-containing compound having a group.

The unsaturated group-containing compound can be bonded to the adhesive resin (I-1a) by further reacting with a functional group in the adhesive resin (I-1a) in addition to the energy ray-polymerizable unsaturated group. It is a compound having a group.
Examples of the energy ray-polymerizable unsaturated group include (meth) acryloyl group, vinyl group (ethenyl group), allyl group (2-propenyl group) and the like, and (meth) acryloyl group is preferable.
Examples of the group that can be bonded to the functional group in the adhesive resin (I-1a) include an isocyanate group and a glycidyl group that can be bonded to a hydroxyl group or an amino group, and a hydroxyl group and an amino group that can be bonded to a carboxy group or an epoxy group. And so on.

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

The pressure-sensitive adhesive resin (I-2a) contained in the pressure-sensitive adhesive composition (I-2) or (I-3) may be only one type, may be two or more types, and if there are two or more types, those. The combination and ratio can be selected arbitrarily.

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

[Energy ray curable compound]
Examples of the energy ray-curable compound in the pressure-sensitive adhesive compositions (I-1) and (I-3) include monomers or oligomers having an energy ray-polymerizable unsaturated group and curable by irradiation with energy rays. Be done.

Among the energy ray-curable compounds, examples of the monomer include trimethylpropantri (meth) acrylate, pentaerythritol (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,4. Polyvalent (meth) acrylates such as −butylene glycol di (meth) acrylate, 1,6-hexanediol (meth) acrylate; urethane (meth) acrylate; polyester (meth) acrylate; polyether (meth) acrylate; epoxy ( Meta) Acrylate and the like can be mentioned.
Among the energy ray-curable compounds, examples of the oligomer include an oligomer obtained by polymerizing the monomers exemplified above.

The energy ray-curable compound contained in the pressure-sensitive adhesive composition (I-1) or (I-3) may be only one kind, two or more kinds, and when two or more kinds, a combination thereof and The ratio can be selected arbitrarily.

In the pressure-sensitive adhesive composition (I-1), the ratio of the content 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 0.01 to 300 parts by mass with respect to 100 parts by mass of the content of the pressure-sensitive adhesive resin (I-2a). Is preferable.

[Crosslinking agent]
When the acrylic polymer having a structural unit derived from a functional group-containing monomer in addition to the structural unit derived from the (meth) acrylic acid alkyl ester is used as the adhesive resin (I-1a), the pressure-sensitive adhesive composition ( I-1) preferably further contains a cross-linking agent.
Further, when the acrylic polymer having a structural unit derived from a functional group-containing monomer similar to that in the adhesive resin (I-1a) is used as the adhesive resin (I-2a), the pressure-sensitive adhesive composition is used. The substance (I-2) or (I-3) may further contain a cross-linking agent.

The cross-linking agent reacts with the functional group, for example, to cross-link the adhesive resins (I-1a) or the adhesive resins (I-2a).
Examples of the cross-linking agent include isocyanate-based cross-linking agents such as tolylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, and adducts of these diisocyanates (cross-linking agents having an isocyanate group); and epoxy-based cross-linking agents such as ethylene glycol glycidyl ether (cross-linking agents). Crosslinking agent having a glycidyl group); Isocyanate-based crosslinking agent such as hexa [1- (2-methyl) -aziridinyl] triphosphatriazine (crosslinking agent having an aziridinyl group); Metal chelate-based crosslinking agent such as aluminum chelate (metal) Crosslinking agent having a chelate structure); Isocyanurate-based crosslinking agent (crosslinking agent having an isocyanate skeleton) and the like can be mentioned.

The cross-linking agent contained in the pressure-sensitive adhesive composition (I-1) or (I-2) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof may be arbitrary. You can choose.

In the pressure-sensitive adhesive composition (I-1), the content of the cross-linking agent is preferably 0.01 to 50 parts by mass with respect to 100 parts by mass of the content of the pressure-sensitive adhesive resin (I-1a). For example, it may be any one of 0.01 to 35 parts by mass and 0.01 to 20 parts by mass.
In the pressure-sensitive adhesive composition (I-2) or (I-3), the content of the cross-linking agent is 0.01 to 50 parts by mass with respect to 100 parts by mass of the content of the pressure-sensitive adhesive resin (I-2a). For example, it may be any one of 0.01 to 35 parts by mass, 0.01 to 20 parts by mass, and 0.01 to 10 parts by mass.

[Photopolymerization initiator]
The pressure-sensitive adhesive compositions (I-1) to (I-3) may further contain a photopolymerization initiator. The pressure-sensitive adhesive compositions (I-1) to (I-3) containing the photopolymerization initiator sufficiently proceed with the curing reaction even when irradiated with relatively low-energy energy rays such as ultraviolet rays.

Examples of the photopolymerization initiator include benzoin compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, methyl benzoin benzoate, and benzoin dimethyl ketal; acetophenone and 2-hydroxy. -2-Methyl-1-phenyl-propane-1-one, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-hydroxy-1- (4- (4- (2-hydroxy-2)) Acetphenone compounds such as −methylpropionyl) benzyl) phenyl) -2-methylpropan-1-one; bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide Acylphosphine oxide compounds such as benzylphenyl sulfide, sulfide compounds such as tetramethylthium monosulfide; α-ketol compounds such as 1-hydroxycyclohexylphenylketone; azo compounds such as azobisisobutyronitrile; titanosen such as titanosen. Compounds; thioxanthone compounds such as thioxanthone; peroxide compounds; diketone compounds such as diacetyl; benzyl; dibenzyl; benzophenone; 2,4-diethylthioxanthone; 1,2-diphenylmethane; 2-hydroxy-2-methyl-1- [4- (1-Methylvinyl) phenyl] propanone; examples thereof include quinone compounds such as 1-chloroanthraquinone and 2-chloroanthraquinone.
Further, as the photopolymerization initiator, for example, a photosensitizer such as amine can be used.

The photopolymerization initiators contained in the pressure-sensitive adhesive compositions (I-1) to (I-3) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof are It can be selected arbitrarily.

In the pressure-sensitive adhesive composition (I-1), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of the content of the energy ray-curable compound.
In the pressure-sensitive adhesive composition (I-2), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of the content of the pressure-sensitive adhesive resin (I-2a). For example, it may be any one of 0.01 to 10 parts by mass and 0.01 to 5 parts by mass.
In the pressure-sensitive adhesive composition (I-3), the content of the photopolymerization initiator is 0.01 to 100 parts by mass with respect to 100 parts by mass of the total content of the pressure-sensitive adhesive resin (I-2a) and the energy ray-curable compound. It is preferably 20 parts by mass.

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

[Other additives]
The pressure-sensitive adhesive compositions (I-1) to (I-3) may contain other additives that do not fall under any of the above-mentioned components as long as the effects of the present invention are not impaired.
Examples of the other additives include antistatic agents, antioxidants, softeners (plasticizers), fillers, rust inhibitors, colorants (pigments, dyes), sensitizers, tackifiers, and reaction delays. Known additives such as agents and cross-linking accelerators (catalysts) can be mentioned.
The reaction retarders are, for example, the pressure-sensitive adhesive compositions (I-1) to (I-1) to be stored due to the action of the catalyst mixed in the pressure-sensitive adhesive compositions (I-1) to (I-3). In I-3), it suppresses the progress of an unintended cross-linking reaction. Examples of the reaction retarder include those that form a chelate complex by chelating to a catalyst, and more specifically, those having two or more carbonyl groups (-C (= O)-) in one molecule. Can be mentioned.

The other additives contained in the pressure-sensitive adhesive compositions (I-1) to (I-3) may be only one type, two or more types, and when two or more types, the combination and ratio thereof are It can be selected arbitrarily.

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 depending on the type thereof.

[solvent]
The pressure-sensitive adhesive compositions (I-1) to (I-3) may contain a solvent. Since the pressure-sensitive adhesive compositions (I-1) to (I-3) contain a solvent, the suitability for coating on the surface to be coated is improved.
In the present specification, the term "solvent" is a concept that includes not only a solvent that dissolves the target component but also a dispersion medium that disperses the target component, unless otherwise specified.

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

The solvent contained in the pressure-sensitive adhesive compositions (I-1) to (I-3) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof may be arbitrarily selected. it can.

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.

<< Manufacturing method of adhesive composition >>
The pressure-sensitive adhesive compositions such as the pressure-sensitive adhesive compositions (I-1) to (I-3) are for forming a pressure-sensitive adhesive composition such as the pressure-sensitive adhesive and, if necessary, components other than the pressure-sensitive adhesive. It is obtained by blending each component.
The order of addition of each component at the time of blending is not particularly limited, and two or more kinds of components may be added at the same time.
The method of mixing each component at the time of blending is not particularly limited, and from known methods such as a method of rotating a stirrer or a stirring blade to mix; a method of mixing using a mixer; a method of adding ultrasonic waves to mix. It may be selected as appropriate.
The temperature and time at the time of adding and mixing 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.

◇ Protective film forming film The protective film forming film can form a protective film forming composite sheet by laminating with a support sheet provided with an adhesive layer, for example, as will be described later.

The protective film forming film forms a protective film for protecting any part of the work and the work work. When the work is a semiconductor wafer, by using the protective film forming film of the present embodiment, the surface opposite to the circuit forming surface of the semiconductor wafer and the semiconductor chip (in any case in the present specification). A protective film can be formed on the "back surface"). In the present specification, a workpiece having a protective film as described above may be referred to as a "work workpiece with a protective film", and a semiconductor chip having a protective film on the back surface is referred to as a "semiconductor chip with a protective film". Sometimes referred to.
The protective film-forming film is soft and can be easily attached to an object to be attached such as a work and a workpiece.

The protective film-forming film may function as a protective film by its curing, or may function as a protective film in an uncured state. The protective film-forming film that functions as a protective film in a non-cured state can be regarded as having formed a protective film, for example, when it is attached to a target portion of the work.

As described above, the protective film-forming film may be curable or non-curable.
The curable protective film forming film may be either thermosetting or energy ray curable, and may have both thermosetting and energy ray curable properties.
As used herein, the term "non-curable" means a property that does not cure by any means such as heating or irradiation with energy rays.

When the protective film-forming film is thermoset to form a protective film, unlike the case where the protective film is cured by irradiation with energy rays, the protective film-forming film is heated even if its thickness becomes thicker. Since it is sufficiently cured, a protective film having high protective performance can be formed. Further, by using a normal heating means such as a heating oven, a large number of protective film forming films can be collectively heated and thermoset.
When the protective film forming film is cured by irradiation with energy rays to form a protective film, unlike the case of thermosetting, the protective film forming composite sheet does not need to have heat resistance and has a wide range. It is possible to construct a composite sheet for forming a protective film. In addition, it can be cured in a short time by irradiating with energy rays.
When the protective film forming film is used as a protective film without being cured, the curing step can be omitted, so that the workpiece with the protective film can be manufactured by a simplified process.

Protective film regardless of whether the protective film forming film is curable or non-curable, and if it is curable, whether it is thermosetting or energy ray curable. The forming film may be composed of one layer (single layer) or may be composed of a plurality of layers of two or more layers. When the protective film forming film is 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.

Protective film regardless of whether the protective film forming film is curable or non-curable, and if it is curable, whether it is thermosetting or energy ray curable. The thickness of the forming film is preferably 1 to 100 μm, more preferably 3 to 80 μm, particularly preferably 5 to 60 μm, and for example, any one of 5 to 40 μm and 5 to 20 μm. It may be. When the thickness of the protective film forming film is at least the above lower limit value, a protective film having higher protective ability can be formed. When the thickness of the protective film forming film is not more than the above upper limit value, it is possible to avoid an excessive thickness.
Here, the "thickness of the protective film forming film" means the thickness of the entire protective film forming film, and for example, the thickness of the protective film forming film composed of a plurality of layers means the protective film forming film. It means the total thickness of all the layers that make up.

In the protective film forming composite sheet of the first embodiment, the glass transition temperature (Tg) of the protective film forming film is preferably 3 ° C. or higher, more preferably 5 ° C. or higher, further preferably 15 ° C. or higher, for example, 10 ° C. The temperature is 20 ° C. or higher. When the glass transition temperature of the protective film forming film is equal to or higher than the lower limit value, the components are transferred to each other between the energy ray-curable pressure-sensitive adhesive layer before energy ray curing and the protective film forming film. This can be suppressed, and when the semiconductor chip with the protective film is picked up from the support sheet, the effect of being able to peel the semiconductor chip with the protective film from the support sheet without peeling between the semiconductor chip and the protective film is more effective. improves.

In the protective film-forming composite sheet of the second embodiment, the glass transition temperature (Tg) of the protective film-forming film is 3 ° C. or higher, preferably 5 ° C. or higher, more preferably 15 ° C. or higher, and further 20 ° C. or higher. Preferably, for example, it is 10 ° C. or higher. When the glass transition temperature of the protective film forming film is equal to or higher than the lower limit value, even if the gel fraction of the pressure-sensitive adhesive layer before energy ray curing is 20% or more and less than 80%, the said before energy ray curing. It is possible to suppress the mutual transfer of components between the energy ray-curable pressure-sensitive adhesive layer and the protective film-forming film, and when picking up the protective film-attached semiconductor chip from the support sheet, the semiconductor chip It is possible to peel off the semiconductor chip with the protective film from the support sheet without peeling off from 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 elastic modulus E ″ of the protective film forming film at 23 ° C. is preferably 3 MPa or more, more preferably 5 MPa or more. Preferably, for example, it is 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, and the like.
The upper limit of the loss elastic modulus E ″ of the protective film forming film at 23 ° C. is not particularly limited. For example, a protective film forming film having a pressure of 100 MPa or less can be easily produced.

The glass transition temperature (Tg) of the protective film forming film and the loss elastic modulus E ″ at 23 ° C. can be measured by a known method. Specifically, it can be measured by the following method.
A laminate obtained by laminating samples to a thickness of about 200 μm is processed into a size of 4 mm in width and 30 mm in length (distance between chucks) to prepare a test piece. Using an automatic dynamic viscoelasticity tester (manufactured by Orientec, product name "Rheovibron DDV-0.1FP"), the tensile loss elastic modulus E'' at 23 ° C. was measured at a measurement frequency of 1 Hz. The peak temperature of tan δ at that time is defined as the glass transition temperature (Tg).

<< Composition for forming a protective film >>
The protective film-forming film can be formed by using a protective film-forming composition containing the constituent material. For example, a protective film-forming film can be formed by applying a protective film-forming composition to the surface to be formed and drying it if necessary. The ratio of the contents of the components that do not vaporize at room temperature in the protective film-forming composition is usually the same as the ratio of the contents of the components in the protective film-forming film.
The thermosetting protective film forming film can be formed by using the thermosetting protective film forming composition, and the energy ray curable protective film forming film can be formed by using the energy ray curable protective film forming composition. The film for forming a non-curable protective film can be formed by using a composition for forming a non-curable protective film. In the present specification, when the protective film-forming film has both thermosetting and energy ray-curable properties, the thermosetting of the protective film-forming film contributes to the formation of the protective film. If the contribution is greater than the contribution of energy ray curing, the protective film forming film is treated as thermosetting. On the contrary, when the contribution of the energy ray curing of the protective film forming film to the formation of the protective film is larger than the contribution of thermosetting, the protective film forming film is treated as one of energy ray curing.

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

Protective film regardless of whether the protective film forming film is curable or non-curable, and if it is curable, whether it is thermosetting or energy ray curable. The drying conditions of the forming composition are not particularly limited. However, when the protective film-forming composition contains a solvent described later, it is preferably heat-dried. Then, the composition for forming a protective film containing a solvent is preferably heat-dried at 70 to 130 ° C. for 10 seconds to 5 minutes, for example. However, the thermosetting protective film-forming composition is preferably heat-dried so that the composition itself and the thermosetting protective film-forming film formed from the composition are 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.

◎ Thermosetting protective film forming film When the thermosetting protective film forming film is attached to the target part of the work and heat-cured to form the protective film, the protective film is sufficient. The degree of curing is not particularly limited as long as the degree of curing is such that it exhibits its function, and it may be appropriately selected depending on the type of the thermosetting protective film forming film.
For example, the heating temperature of the thermosetting protective film forming film at the time of thermosetting is preferably 100 to 200 ° C., more preferably 110 to 180 ° C., and particularly preferably 120 to 170 ° C. .. The heating time during the thermosetting 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 forming a thermosetting protective film, for example, a film containing a polymer component (A) and a thermosetting component (B) can be mentioned. The polymer component (A) is a component that can be regarded as being formed by a polymerization reaction of a polymerizable compound. The thermosetting component (B) is a component capable of undergoing a curing (polymerization) reaction using heat as a trigger for the reaction. In the present specification, the polymerization reaction also includes a polycondensation reaction.

<Composition for forming a thermosetting protective film (III-1)>
As a preferable composition for forming a thermosetting protective film, for example, a composition for forming a thermosetting protective film (III-1) containing the polymer component (A) and the thermosetting component (B) (the present specification). In the book, it may be simply abbreviated as "composition (III-1)") and the like.

[Polymer component (A)]
The polymer component (A) is a component for imparting film-forming property, flexibility, etc. to the thermosetting protective film forming film.
The polymer component (A) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind, two or more kinds, or a combination thereof when there are two or more kinds. And the ratio can be selected arbitrarily.

Examples of the polymer component (A) include acrylic resin, polyester, urethane resin, acrylic urethane resin, silicone resin, rubber resin, phenoxy resin, thermoplastic polyimide, and the like, and acrylic resin is preferable.

Examples of the acrylic resin in the polymer component (A) include known acrylic polymers.
The weight average molecular weight (Mw) of the acrylic resin is preferably 1000 to 2000000, and more preferably 100,000 to 1500,000. When the weight average molecular weight of the acrylic resin is at least the above lower limit value, the shape stability (stability with time during storage) of the film for forming a thermosetting protective film is improved. Further, when the weight average molecular weight of the acrylic resin is not more than the above upper limit value, the film for forming a thermosetting protective film easily follows the uneven surface of the adherend, and the adherend and the thermosetting protective film are formed. The generation of voids and the like with the film is further suppressed.
In the present specification, the "weight average molecular weight" is a polystyrene-equivalent value measured by a gel permeation chromatography (GPC) method unless otherwise specified.

The glass transition temperature (Tg) of the acrylic resin is preferably 3 ° C. or higher and 70 ° C. or lower, and more preferably 3 ° C. or higher and 50 ° C. or lower. When the Tg of the acrylic resin is at least the above lower limit value, it is possible to suppress the mutual transfer of the components between the energy ray-curable pressure-sensitive adhesive and the protective film-forming film before the energy ray-curing. This makes it possible to further improve the effect of peeling the semiconductor chip with the protective film from the support sheet without peeling between the semiconductor chip and the protective film when the semiconductor chip with the protective film is picked up from the support sheet. Further, when the Tg of the acrylic resin is not more than the above upper limit value, the adhesive force between the thermosetting protective film forming film and the cured product thereof is improved.

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

Examples of the (meth) acrylic acid ester constituting the acrylic resin include methyl (meth) acrylic acid, ethyl (meth) acrylic acid, n-propyl (meth) acrylic acid, isopropyl (meth) acrylic acid, and (meth). ) N-butyl acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, (meth) acrylic Heptyl acid, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, n-octyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate , (Meta) undecyl acrylate, (meth) dodecyl acrylate ((meth) lauryl acrylate), (meth) tridecyl acrylate, tetradecyl (meth) acrylate (myristyl (meth) acrylate), (meth) acrylate Alkyl groups constituting alkyl esters such as pentadecyl, hexadecyl (meth) acrylate (palmityl (meth) acrylate), heptadecyl (meth) acrylate, octadecyl (meth) acrylate (stearyl (meth) acrylate), etc. (Meta) acrylic acid alkyl ester having a chain structure with 1 to 18 carbon atoms;
(Meta) Acrylic acid cycloalkyl esters such as (meth) acrylate isobornyl, (meth) acrylate dicyclopentanyl;
(Meta) Acrylic acid aralkyl esters such as benzyl (meth) acrylic acid;
(Meta) Acrylic acid cycloalkenyl ester such as (meth) acrylic acid dicyclopentenyl ester;
(Meta) Acrylic acid cycloalkenyloxyalkyl ester such as (meth) acrylic acid dicyclopentenyloxyethyl ester;
(Meta) acrylate imide;
A glycidyl group-containing (meth) acrylic acid ester such as glycidyl (meth) acrylate;
Hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, (meth) ) Hydroxyl-containing (meth) acrylic acid esters such as 3-hydroxybutyl acrylate and 4-hydroxybutyl (meth) acrylate;
Examples thereof include substituted amino group-containing (meth) acrylic acid esters such as N-methylaminoethyl (meth) acrylic acid. Here, the "substituted amino group" means a group in which one or two hydrogen atoms of the amino group are substituted with a group other than the hydrogen atom.

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

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

The acrylic resin may have a functional group capable of binding to other compounds such as a vinyl group, a (meth) acryloyl group, an amino group, a hydroxyl group, a carboxy group and an isocyanate group. The functional group of the acrylic resin may be bonded to another compound via a cross-linking agent (F) described later, or may be directly bonded to another compound without a cross-linking 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 the acrylic resin (hereinafter, may be simply abbreviated as “thermoplastic resin”) is used alone without using the acrylic resin. Alternatively, it may be used in combination with an acrylic resin. By using the thermoplastic resin, the peelability of the protective film from the support sheet is improved, and the film for forming the thermosetting protective film easily follows the uneven surface of the adherend, so that the adherend and the thermosetting are thermally cured. The generation of voids and the like may be further suppressed with the film for forming the sex protective film.

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

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

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

The thermoplastic resin contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind, two or more kinds, and when two or more kinds, a combination and a ratio thereof. Can be selected arbitrarily.

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

The polymer component (A) may also correspond to the thermosetting component (B). In the present invention, when the composition (III-1) contains a component corresponding to both the polymer component (A) and the thermosetting component (B), the composition (III-1) is used. , The polymer component (A) and the thermosetting component (B) are considered to be contained.

[Thermosetting component (B)]
The thermosetting component (B) is a component for curing a film for forming a thermosetting protective film.
The thermosetting component (B) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind, two or more kinds, and when two or more kinds, those The combination and ratio can be selected arbitrarily.

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

(Epoxy thermosetting resin)
The epoxy-based thermosetting resin is composed of an epoxy resin (B1) and a thermosetting agent (B2).
The epoxy-based thermosetting resin contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one type, two or more types, or a combination thereof when two or more types are used. And the ratio can be selected arbitrarily.

・ Epoxy resin (B1)
Examples of the epoxy resin (B1) include known ones, such as polyfunctional epoxy resin, biphenyl compound, bisphenol A diglycidyl ether and its hydrogenated product, orthocresol novolac epoxy resin, and 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 functional epoxy compounds can be mentioned.

As the epoxy resin (B1), an epoxy resin having an unsaturated hydrocarbon group may be used. Epoxy resins having unsaturated hydrocarbon groups have higher compatibility with acrylic resins than epoxy resins having no unsaturated hydrocarbon groups. Therefore, by using an epoxy resin having an unsaturated hydrocarbon group, the reliability of the work piece with a protective film obtained by using the composite sheet for forming a protective film is improved.

Examples of the epoxy resin having an unsaturated hydrocarbon group include a compound obtained by converting a part of the epoxy group of the polyfunctional epoxy resin into a group having an unsaturated hydrocarbon group. Such a compound can be obtained, for example, by subjecting an epoxy group to an addition reaction of (meth) acrylic acid or a derivative thereof.
Examples of the epoxy resin having an unsaturated hydrocarbon group include a compound in which a group having an unsaturated hydrocarbon group is directly bonded to an aromatic ring or the like constituting the epoxy resin.
The unsaturated hydrocarbon group is a polymerizable unsaturated group, and specific examples thereof include an ethenyl group (vinyl group), a 2-propenyl group (allyl group), a (meth) acryloyl group, and a (meth) group. Examples thereof include an acrylamide group, and an acryloyl group is preferable.

The number average molecular weight of the epoxy resin (B1) is not particularly limited, but is 300 to 30,000 from the viewpoint of the curability of the thermosetting protective film forming film and the strength and heat resistance of the cured protective film. It is preferably 300 to 10000, more preferably 300 to 3000, and particularly preferably 300 to 3000.
The epoxy equivalent of the epoxy resin (B1) is preferably 100 to 1000 g / eq, more preferably 150 to 950 g / eq.

As the epoxy resin (B1), one type may be used alone, two or more types may be used in combination, and when two or more types are used in combination, the combination and ratio thereof can be arbitrarily selected.

・ Thermosetting agent (B2)
The thermosetting agent (B2) functions as a curing agent for the epoxy resin (B1).
Examples of the thermosetting agent (B2) include compounds having two or more functional groups capable of reacting with epoxy groups in one molecule. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxy group, a group in which an acid group is anhydrous, and the phenolic hydroxyl group, an amino group, or an acid group is anhydrous. It is preferably a group, more preferably a phenolic hydroxyl group or an amino group.

Among the heat-curing agents (B2), examples of the phenol-based curing agent having a phenolic hydroxyl group include polyfunctional phenol resins, biphenols, novolak-type phenol resins, dicyclopentadiene-type phenol resins, and aralkyl-type phenol resins. ..
Among the thermosetting agents (B2), examples of the amine-based curing agent having an amino group include dicyandiamide and the like.

The thermosetting agent (B2) may have an unsaturated hydrocarbon group.
The thermosetting agent (B2) having an unsaturated hydrocarbon group is, for example, a compound in which a part of the hydroxyl group of the phenol resin is replaced with a group having an unsaturated hydrocarbon group, which is not suitable for the aromatic ring of the phenol resin. Examples thereof include compounds in which a group having a saturated hydrocarbon group is directly bonded.
The unsaturated hydrocarbon group in the thermosetting agent (B2) is the same as the unsaturated hydrocarbon group in the epoxy resin having the unsaturated hydrocarbon group described above.

When a phenolic curing agent is used as the thermosetting agent (B2), the thermosetting agent (B2) has a high softening point or glass transition temperature because the peelability of the protective film from the support sheet is improved. preferable.

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. , 400 to 10000, more preferably 500 to 3000.
The molecular weight of the non-resin component such as biphenol and dicyandiamide in the thermosetting agent (B2) is not particularly limited, but is preferably 60 to 500, for example.

As the thermosetting agent (B2), one type may be used alone, two or more types may be used in combination, and when two or more types are used in combination, the combination and ratio thereof can be arbitrarily selected.

In the composition (III-1) and the film for forming a thermosetting protective film, the content of the thermosetting agent (B2) is 0.1 to 100% by mass with respect to 100 parts by mass of the content of the epoxy resin (B1). It is preferably parts, more preferably 0.5 to 50 parts by mass, and for example, any one of 0.5 to 25 parts by mass, 0.5 to 10 parts by mass, and 0.5 to 5 parts by mass. It may be. When the content of the thermosetting agent (B2) is at least the lower limit value, the curing of the thermosetting protective film forming film becomes easier to proceed. When the content of the thermosetting agent (B2) is not more than the upper limit value, the hygroscopicity of the thermosetting protective film forming film is reduced, and the package obtained by using the protective film forming composite sheet is used. The reliability 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 determined. The content of the polymer component (A) is preferably 5 to 120 parts by mass, more preferably 5 to 80 parts by mass, and for example, 5 to 40 parts by mass and 5 to 20 parts by mass with respect to 100 parts by mass. It may be any of 40 to 80 parts by mass, 50 to 75 parts by mass, and 60 to 75 parts by mass. When the content of the thermosetting component (B) is in such a range, for example, the adhesive force 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. To do.

[Curing 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, for example, 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-hydroxymethylimidazole and other imidazoles (one or more hydrogen atoms other than hydrogen atoms) (Imidazole substituted with an organic group); organic phosphines such as tributylphosphine, diphenylphosphine, triphenylphosphine (phosphine in which one or more hydrogen atoms are substituted with an organic group); tetraphenylphosphonium tetraphenylborate, triphenylphosphine Examples thereof include tetraphenylborone salts such as tetraphenylborate.

The curing accelerator (C) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one type, two or more types, or a combination thereof when two or more types are used. And the ratio can be selected arbitrarily.

When the curing accelerator (C) is used, the content of the curing accelerator (C) in the composition (III-1) and the film for forming a thermosetting protective film is 100, which is the content of the thermosetting component (B). It is preferably 0.01 to 10 parts by mass, and more preferably 0.1 to 7 parts by mass with respect to parts by mass. When the content of the curing accelerator (C) is at least the lower limit value, the effect of using the curing accelerator (C) is more remarkable. When the content of the curing accelerator (C) is not more than the above upper limit value, for example, the highly polar curing accelerator (C) is coated in the thermosetting protective film forming film under high temperature and high humidity conditions. The effect of suppressing segregation by moving to the adhesion interface side with the body is enhanced. As a result, the reliability of the work piece with the protective film obtained by using the composite sheet for forming the protective film is further improved.

[Filler (D)]
The composition (III-1) and the film for forming a thermosetting protective film may contain a filler (D). Since the thermosetting protective film forming film contains the filler (D), the thermosetting protective film forming film and its cured product (that is, the protective film) can easily adjust the thermal expansion coefficient, and this heat By optimizing the expansion coefficient for the object to be formed of the protective film, the reliability of the work piece with the protective film obtained by using the composite sheet for forming the protective film is further improved. Further, when the thermosetting protective film forming film contains the filler (D), the hygroscopicity of the protective film can be reduced and the heat dissipation can be improved.

The filler (D) may be either an organic filler or an inorganic filler, but is preferably an inorganic filler.
Preferred inorganic fillers include, for example, powders of silica, alumina, talc, calcium carbonate, titanium white, red iron oxide, silicon carbide, boron nitride and the like; spherical beads of these inorganic fillers; surface modification of these inorganic fillers. Goods; Single crystal fibers of these inorganic fillers; Glass fibers and the like.
Among these, the inorganic filler is preferably silica or alumina, and more preferably silica.

The filler (D) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind, two or more kinds, and when two or more kinds, a combination thereof and The ratio can be selected arbitrarily.

In the composition (III-1), the ratio of the content of the filler (D) to the total content of all the components other than the solvent (that is, the formation of a thermosetting protective film in the film for forming a thermosetting protective film). The ratio of the content of the filler (D) to the total mass of the film for use) is preferably 50% by mass or more, 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, for example, 50% by mass or more and 80% by mass or less, and 55% by mass. It may be any of more than 80% by mass or less, 50% by mass or more and 70% by mass or less, and 55% by mass or more and 70% by mass or less. When the ratio is in such a range, it is possible to prevent the components from being transferred to each other between the energy ray-curable pressure-sensitive adhesive and the protective film-forming film before the 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, it is possible to improve the adhesiveness and adhesion of the thermosetting protective film forming film to the adherend. it can. Further, by using the coupling agent (E), the cured product of the thermosetting protective film forming film has improved water resistance without impairing heat resistance.

The coupling agent (E) is preferably a compound having a functional group capable of reacting with the functional groups of the polymer component (A), the thermosetting component (B), and the like, and is preferably a silane coupling agent. More preferred.
Preferred silane coupling agents include, for example, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxymethyldiethoxysilane, 2-. (3,4-Epoxycyclohexyl) ethyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3- (2-aminoethylamino) propyltrimethoxysilane, 3- (2-amino) Ethylamino) propylmethyldiethoxysilane, 3- (phenylamino) propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyl Examples thereof include dimethoxysilane, bis (3-triethoxysilylpropyl) tetrasulfane, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, and imidazolesilane.

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

When the 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 the polymer component (A) and the thermosetting component. The total content of (B) is preferably 0.03 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and 0.1 to 2 parts by mass with respect to 100 parts by mass. Is particularly preferable. When the content of the coupling agent (E) is equal to or higher than the lower limit, the dispersibility of the filler (D) in the resin is improved and the thermosetting protective film forming film is adhered to the adherend. The effect of using the coupling agent (E), such as improvement of the property, can be obtained more remarkably. Further, when the content of the coupling agent (E) is not more than the upper limit value, the generation of outgas is further suppressed.

[Crosslinking agent (F)]
As the polymer component (A), one having a functional group such as a vinyl group capable of binding to another compound, a (meth) acryloyl group, an amino group, a hydroxyl group, a carboxy group, an isocyanate group, etc., such as the above-mentioned acrylic resin, is used. When used, the composition (III-1) and the thermosetting protective film-forming film may contain a cross-linking agent (F). The cross-linking agent (F) is a component for bonding the functional group in the polymer component (A) with another compound to cross-link, and by cross-linking in this way, a film for forming a thermosetting protective film. The initial adhesive force and cohesive force of the

Examples of the cross-linking agent (F) include an organic polyvalent isocyanate compound, an organic polyvalent imine compound, a metal chelate-based cross-linking agent (cross-linking agent having a metal chelate structure), an aziridine-based cross-linking agent (cross-linking agent having an aziridinyl group), and the like. Can be mentioned.

The cross-linking agent (F) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind, two or more kinds, and when two or more kinds, a combination thereof and The ratio can be selected arbitrarily.

When the cross-linking agent (F) is used, the content of the cross-linking agent (F) in the composition (III-1) is 0.01 to 20 mass by mass with respect to 100 parts by mass of the content of the polymer component (A). It is preferably 0.1 to 10 parts by mass, and particularly preferably 0.5 to 5 parts by mass. When the content of the cross-linking agent (F) is at least the lower limit value, the effect of using the cross-linking agent (F) is more remarkable. Further, when the content of the cross-linking agent (F) is not more than the upper limit value, the excessive use of the cross-linking 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 thermosetting protective film forming film contains the energy ray-curable resin (G), its characteristics 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 compounds having at least one polymerizable double bond in the molecule, and acrylate-based compounds having a (meth) acryloyl group are preferable.

Examples of the acrylate-based compound include trimethylolpropantri (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, and dipentaerythritol monohydroxypenta (dipentaerythritol monohydroxypenta). Chain aliphatic skeleton-containing (meth) acrylates such as meta) acrylates, dipentaerythritol hexa (meth) acrylates, 1,4-butylene glycol di (meth) acrylates, and 1,6-hexanediol di (meth) acrylates; Cyclic aliphatic skeleton-containing (meth) acrylate such as cyclopentanyldi (meth) acrylate; Polyalkylene glycol (meth) acrylate such as polyethylene glycol di (meth) acrylate; Oligoester (meth) acrylate; Urethane (meth) acrylate oligomer ; Epoxy-modified (meth) acrylate; polyether (meth) acrylate other than the polyalkylene glycol (meth) acrylate; itaconic acid oligomer and the like.

The weight average molecular weight of the energy ray-curable compound is preferably 100 to 30,000, more preferably 300 to 10,000.

The energy ray-curable compound used for the polymerization may be only one kind, may be two or more kinds, and when there are two or more kinds, the combination and ratio 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 kind, two or more kinds, and when two or more kinds, they may be used. The combination and ratio of are arbitrarily selectable.

When the energy ray-curable resin (G) is used, the ratio of the content of the energy ray-curable resin (G) to the total mass of the composition (III-1) in the composition (III-1) is 1 to 1. It is preferably 95% by mass, more preferably 5 to 90% by mass, and particularly preferably 10 to 85% by 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), light is used to efficiently proceed with the polymerization reaction of the energy ray-curable resin (G). It may contain a polymerization initiator (H).

Examples of the photopolymerization initiator (H) in the composition (III-1) include the same photopolymerization initiators that may be contained in the above-mentioned pressure-sensitive adhesive composition.

The photopolymerization initiator (H) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind, two or more kinds, and when two or more kinds, those The combination and ratio can be selected arbitrarily.

When the photopolymerization initiator (H) is used, in the composition (III-1), the content of the photopolymerization initiator (H) is based on 100 parts by mass of the content of the energy ray-curable resin (G). It is preferably 0.1 to 20 parts by mass, more preferably 1 to 10 parts by mass, and particularly preferably 2 to 5 parts by mass.

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

Examples of the colorant (I) include known ones such as inorganic pigments, organic pigments, and organic dyes.

Examples of the organic pigments and organic dyes include aminium pigments, cyanine pigments, merocyanine pigments, croconium pigments, squalium pigments, azulenium pigments, polymethine pigments, naphthoquinone pigments, pyrylium pigments, and phthalocyanines. Colors, naphthalocyanine pigments, naphtholactam pigments, azo pigments, condensed azo pigments, indigo pigments, perinone pigments, perylene pigments, dioxazine pigments, quinacridone pigments, isoindolinone pigments, quinophthalone pigments , Pyrrole pigments, thioindigo pigments, metal complex pigments (metal complex salt dyes), dithiol metal complex pigments, indolphenol pigments, triallylmethane pigments, anthraquinone pigments, dioxazine pigments, naphthol pigments, azomethine pigments. Examples thereof include pigments, benzimidazolone pigments, pyranthron pigments and slene pigments.

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, and ITO ( Examples thereof include indium tin oxide) dyes and ATO (antimons tin oxide) dyes.

The colorant (I) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind, two or more kinds, and when two or more kinds, a combination thereof and The ratio can be selected arbitrarily.

When the colorant (I) is used, the content of the colorant (I) in the thermosetting protective film forming film may be appropriately adjusted according to the intended purpose. For example, by adjusting the content of the colorant (I) of the thermosetting protective film forming film and adjusting the light transmission of the protective film, the print visibility when laser printing is performed on the protective film. Can be adjusted. Further, by adjusting the content of the colorant (I) of the thermosetting protective film forming film, the design of the protective film can be improved and the grinding marks on the back surface of the semiconductor wafer can be made difficult to see. Considering these points, in the composition (III-1), the ratio of the content of the colorant (I) to the total content of all the components other than the solvent (that is, in the film for forming a thermosetting protective film). The ratio of the content of the colorant (I) to the total mass of the heat-curable protective film forming film) is preferably 0.1 to 10% by mass, preferably 0.1 to 7.5% by mass. It is more preferable, and it is particularly preferable that it is 0.1 to 5% by mass. When the ratio is at least the lower limit value, the effect of using the colorant (I) is more remarkable. Further, when the ratio is not more than the upper limit value, an excessive decrease in light transmittance of the thermosetting protective film forming film is suppressed.

[General-purpose additive (J)]
The composition (III-1) and the film for forming a thermosetting protective film may contain a general-purpose additive (J) as long as the effects of the present invention are not impaired.
The general-purpose additive (J) may be a known one, and may be arbitrarily selected depending on the intended purpose, and is not particularly limited, but preferred ones are, for example, plasticizers, antistatic agents, antioxidants, gettering agents, and the like. Examples include ultraviolet absorbers.

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

[solvent]
The composition (III-1) preferably further contains a solvent. The solvent-containing composition (III-1) has good handleability.
The solvent is not particularly limited, but preferred ones are, for example, hydrocarbons such as toluene and xylene; alcohols such as methanol, ethanol, 2-propanol, isobutyl alcohol (2-methylpropan-1-ol) and 1-butanol. Examples thereof include esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; amides such as dimethylformamide and N-methylpyrrolidone (compounds having an amide bond).
The solvent contained in the composition (III-1) may be only one type, may be two or more types, and when there are two or more types, the combination and ratio thereof can be arbitrarily selected.

Among the solvents contained in the composition (III-1), more preferable ones include, for example, methyl ethyl ketone, toluene, ethyl acetate and the like from the viewpoint that the components contained in the composition (III-1) can be mixed more uniformly. Be done.

The content of the solvent in the composition (III-1) is not particularly limited, and may be appropriately selected depending on, for example, the type of component other than the solvent.

<Manufacturing method of composition for forming a thermosetting protective film>
A composition for forming a thermosetting protective film such as the composition (III-1) can be obtained by blending each component for forming the composition.
The composition for forming a thermosetting protective film can be produced, for example, by the same method as in the case of the pressure-sensitive adhesive composition described above, except that the types of compounding components are different.

◎ Energy ray-curable protective film forming film The protective film is the curing condition when the energy ray-curable protective film forming film is attached to the target part of the work and the energy ray-curable protective film is formed. The degree of curing is not particularly limited as long as the degree of curing is such that the function is sufficiently exhibited, and the film may be appropriately selected depending on the type of the energy ray-curable protective film forming film.
For example, the illuminance of the energy ray at the time of energy ray curing of the energy ray curable protective film forming film is preferably ^{120 to 280 mW / cm 2.} The amount of light of the energy rays at the time of curing is preferably ^{100 to 1000 mJ / cm 2.}

Examples of the film for forming an energy ray-curable protective film include those containing an energy ray-curable component (a), and those containing an energy ray-curable component (a) and a filler are preferable.
In the energy ray-curable protective film forming film, the energy ray-curable component (a) is preferably uncured, preferably has adhesiveness, and more preferably uncured and has adhesiveness.

<Composition for forming an energy ray-curable protective film (IV-1)>
As a preferable composition for forming an energy ray-curable protective film, for example, the composition for forming an energy ray-curable protective film (IV-1) containing the energy ray-curable component (a) (in the present specification, It may be simply abbreviated as "composition (IV-1)") and the like.

[Energy ray curable component (a)]
The energy ray-curable component (a) is a component that is cured by irradiation with energy rays, and imparts film-forming property, flexibility, etc. to the energy ray-curable protective film forming film, and protects the film after curing. It is also a component for forming a film.
Examples of the energy ray-curable component (a) include a polymer (a1) having an energy ray-curable group and having a weight average molecular weight of 80,000 to 2000000, and an energy ray-curable group having a molecular weight of 100 to 80,000. The compound (a2) can be mentioned. The polymer (a1) may be at least partially crosslinked by a crosslinking agent or may not be crosslinked.

(Polymer (a1) having an energy ray-curable group and having a weight average molecular weight of 80,000 to 2000000)
Examples of the polymer (a1) having an energy ray-curable group and having a weight average molecular weight of 80,000 to 2000000 include an acrylic polymer (a11) having a functional group capable of reacting with a group of another compound, and the above-mentioned polymer (a11). Examples thereof include an acrylic resin (a1-1) formed by reacting with a group that reacts with a functional group and an energy ray-curable compound (a12) having an energy ray-curable group such as an energy ray-curable double bond. ..

Examples of the functional group capable of reacting with a group of another compound include a hydroxyl group, a carboxy group, an amino group, and a substituted amino group (one or two hydrogen atoms of the amino group are substituted with a group other than the hydrogen atom. Group), epoxy group and the like. However, in terms of preventing corrosion of circuits such as workpieces and workpieces, the functional group is preferably a group other than the carboxy group.
Among these, the functional group is preferably a hydroxyl group.

-Acrylic polymer having a functional group (a11)
Examples of the acrylic polymer (a11) having the functional group include those obtained by copolymerizing the acrylic monomer having the functional group and the acrylic monomer having no functional group. In addition to the monomer, a monomer other than the acrylic monomer (non-acrylic monomer) may be copolymerized.
Further, the acrylic polymer (a11) may be a random copolymer or a block copolymer, and a known method can be adopted as the polymerization method.

Examples of the acrylic monomer having a functional group include a hydroxyl group-containing monomer, a carboxy 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). (Meta) hydroxyalkyl (meth) acrylates such as 2-hydroxybutyl acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate; non- (meth) acrylics such as vinyl alcohol and allyl alcohol. Saturated alcohol (unsaturated alcohol having no (meth) acrylic skeleton) and the like can be mentioned.

Examples of the carboxy group-containing monomer include ethylenically unsaturated monocarboxylic acids (monocarboxylic acids having ethylenically unsaturated bonds) such as (meth) acrylic acid and crotonic acid; fumaric acid, itaconic acid, maleic acid, and citracon. Ethylene unsaturated dicarboxylic acids such as acids (dicarboxylic acids having ethylenically unsaturated bonds); anhydrides of the ethylenically unsaturated dicarboxylic acids; (meth) acrylic acid carboxyalkyl esters such as 2-carboxyethyl methacrylate and the like. Be done.

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

The acrylic monomer having the functional group constituting the acrylic polymer (a11) may be only one kind, may be two or more kinds, and when there are two or more kinds, the combination and ratio thereof are arbitrary. You can choose.

Examples of the acrylic monomer having no functional group include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, and n (meth) acrylate. -Butyl, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, ( 2-Ethylhexyl acrylate, (meth) isooctyl acrylate, n-octyl acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, (meth) Undecyl acrylate, dodecyl (meth) acrylate (lauryl acrylate), tridecyl (meth) acrylate, tetradecyl (meth) acrylate (myristyl acrylate), pentadecyl (meth) acrylate, (meth) ) Hexadecyl acrylate (palmityl (meth) acrylate), heptadecyl (meth) acrylate, octadecyl (meth) acrylate (stearyl (meth) acrylate) and other alkyl groups constituting the alkyl ester have 1 carbon number. Examples thereof include (meth) acrylic acid alkyl ester having a chain structure of -18.

Examples of the acrylic monomer having no functional group include alkoxy such as methoxymethyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxymethyl (meth) acrylate, and ethoxyethyl (meth) acrylate. Alkyl group-containing (meth) acrylic acid ester; (meth) acrylic acid ester having an aromatic group, including (meth) acrylic acid aryl ester such as phenyl (meth) acrylic acid; non-crosslinkable (meth) acrylamide and Derivatives thereof; (meth) acrylic acid ester having a non-crosslinkable tertiary amino group such as (meth) acrylic acid N, N-dimethylaminoethyl, (meth) acrylic acid N, N-dimethylaminopropyl and the like can also be mentioned. ..

The acrylic monomer having no functional group constituting the acrylic polymer (a11) may be of only one type, may be of two or more types, and when there are two or more types, the combination and ratio thereof are arbitrary. Can be selected.

Examples of the non-acrylic monomer include olefins such as ethylene and norbornene; vinyl acetate; and styrene.
The non-acrylic monomer constituting the acrylic polymer (a11) may be of only one type, may be of two or more types, and when there are two or more types, the combination and ratio 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 a functional group to the total amount of the structural unit constituting the acrylic polymer (a11) is 0.1 to 50 mass by mass. %, More preferably 1 to 40% by mass, and particularly preferably 3 to 30% by mass. When the ratio is in such a range, the energy 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 linear curable group can be easily adjusted to a preferable range in the degree of curing of the protective film.

The acrylic polymer (a11) constituting the acrylic resin (a1-1) may be of only one type, may be of two or more types, and when there are two or more types, the combination and ratio thereof may be arbitrary. You can choose.

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

-Energy ray curable compound (a12)
The energy ray-curable compound (a12) is one or two selected from the group consisting of an isocyanate group, an epoxy group and a carboxy group as a group capable of reacting with the functional group of the acrylic polymer (a11). Those having the above are preferable, and those having an isocyanate group as the group are more preferable. When the energy ray-curable compound (a12) has an isocyanate group as the group, for example, the isocyanate group easily 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 contained in one molecule of the energy ray-curable compound (a12) is not particularly limited, and for example, in consideration of physical properties such as shrinkage rate required for the target protective film. Can be selected as appropriate.
For example, the energy ray-curable compound (a12) preferably has 1 to 5 energy ray-curable groups in one molecule, and more preferably 1 to 3 groups.

Examples of the energy ray-curable compound (a12) include 2-methacryloyloxyethyl isocyanate, meta-isopropenyl-α, α-dimethylbenzyl isocyanate, methacryloyl isocyanate, allyl isocyanate, and 1,1- (bisacryloyloxymethyl). Ethyl isocyanate;
Acryloyl monoisocyanate compound obtained by reaction of diisocyanate compound or polyisocyanate compound with hydroxyethyl (meth) acrylate;
Examples thereof include an acryloyl monoisocyanate compound obtained by reacting a diisocyanate compound or a polyisocyanate compound with a polyol compound and a hydroxyethyl (meth) acrylate.
Among these, the energy ray-curable compound (a12) is preferably 2-methacryloyloxyethyl isocyanate.

The energy ray-curable compound (a12) constituting the acrylic resin (a1-1) may be of only one type, may be of two or more types, and when there are two or more types, the combination and ratio thereof are arbitrary. Can be selected.

In the acrylic resin (a1-1), the content of the energy ray-curable group derived from the energy ray-curable compound (a12) is relative to the content of the functional group derived from the acrylic polymer (a11). The ratio of the above is preferably 20 to 120 mol%, more preferably 35 to 100 mol%, and particularly preferably 50 to 100 mol%. When the content ratio is in such a range, the adhesive force of the cured product of the energy ray-curable protective film forming film becomes larger. When the energy ray-curable compound (a12) is a monofunctional compound (having one group in one molecule), the upper limit of the content ratio is 100 mol%. When the energy ray-curable compound (a12) is a polyfunctional compound (having two or more of the groups in one molecule), the upper limit of the content ratio may exceed 100 mol%.

The weight average molecular weight (Mw) of the polymer (a1) is preferably 100,000 to 20,000, more preferably 300,000 to 1,500,000.
Here, the "weight average molecular weight" is as described above.

When the polymer (a1) is at least partially crosslinked with a cross-linking agent, the polymer (a1) has been described as constituting the acrylic polymer (a11). A monomer that does not correspond to any of the monomers and has a group that reacts with the cross-linking agent may be polymerized and cross-linked at the group that reacts with the cross-linking agent, or the energy ray-curable compound (the energy ray-curable compound). The group that reacts with the functional group derived from a12) may be crosslinked.

The polymer (a1) 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 when two or more types are used. The combination and ratio can be selected arbitrarily.

(Compound (a2) having an energy ray-curable group and having a molecular weight of 100 to 80,000)
Examples of the energy ray-curable group in the compound (a2) having an energy ray-curable group and having a molecular weight of 100 to 80,000 include a group containing an energy ray-curable double bond, and preferred ones are (meth). ) Acryloyl group, vinyl group and the like can be mentioned.

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

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, and 2,2-bis [4. -((Meta) acryloxipolyethoxy) phenyl] propane, ethoxylated bisphenol A di (meth) acrylate, 2,2-bis [4-((meth) acryloxidiethoxy) phenyl] propane, 9,9-bis [4- (2- (meth) acryloyloxyethoxy) phenyl] fluorene, 2,2-bis [4-((meth) acryloyloxypolypropoxy) phenyl] propane, tricyclodecanedimethanol di (meth) acrylate, 1 , 10-decanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (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-((Meta) acryloxyethoxy) phenyl] propane, neopentyl glycol di (meth) acrylate, ethoxylated polypropylene glycol di (meth) acrylate, 2-hydroxy-1,3-di (meth) acryloxypropane, etc. Bifunctional (meth) acrylate;
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, dipentaerythritol poly (meth) acrylate, dipentaerythritol hexa ( Polyfunctional (meth) acrylates such as meta) acrylates;
Examples thereof include polyfunctional (meth) acrylate oligomers such as urethane (meth) acrylate oligomers.

Among the compounds (a2), the epoxy resin having an energy ray-curable group and the phenol resin having an energy ray-curable group are described in, for example, paragraph 0043 of "Japanese Patent Laid-Open No. 2013-194102". Can be used. Such a resin also corresponds to a resin constituting a thermosetting component described later, but is treated as the compound (a2) in the present invention.

The weight average molecular weight of the compound (a2) is preferably 100 to 30,000, more preferably 300 to 10,000.

The compound (a2) contained in the composition (IV-1) and the film for forming an energy ray-curable protective film may be only one kind, two or more kinds, or a combination thereof when there are two or more kinds. And the ratio can be selected arbitrarily.

[Polymer without energy ray-curable group (b)]
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), the polymer does not further have an energy ray-curable group. (B) is also preferably contained.
The polymer (b) may be at least partially crosslinked by a crosslinking agent or may not be crosslinked.

Examples of the polymer (b) having no energy ray-curable group include an acrylic polymer, a phenoxy resin, a urethane resin, a polyester, a rubber resin, and an acrylic urethane resin.
Among these, the polymer (b) is preferably an acrylic polymer (hereinafter, may be abbreviated as "acrylic polymer (b-1)").

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

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

As the (meth) acrylic acid alkyl ester, for example, the acrylic monomer having no functional group (alkyl group constituting the alkyl ester, which constitutes the acrylic polymer (a11) described above, has the number of carbon atoms. (Meta) acrylic acid alkyl ester, etc., which has a chain structure of 1 to 18).

Examples of the (meth) acrylic acid ester having a cyclic skeleton include (meth) acrylic acid cycloalkyl esters such as (meth) acrylic acid isobornyl and (meth) acrylic acid dicyclopentanyl;
(Meta) Acrylic acid aralkyl esters such as benzyl (meth) acrylic acid;
(Meta) Acrylic acid cycloalkenyl ester such as (meth) acrylic acid dicyclopentenyl ester;
Examples thereof include (meth) acrylic acid cycloalkenyloxyalkyl ester such as (meth) acrylic acid dicyclopentenyloxyethyl ester.

Examples of the glycidyl group-containing (meth) acrylic acid ester include glycidyl (meth) acrylic acid.
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. Examples thereof include propyl, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, and 4-hydroxybutyl (meth) acrylate.
Examples of the substituted amino group-containing (meth) acrylic acid ester include N-methylaminoethyl (meth) acrylic acid.

Examples of the non-acrylic monomer constituting the acrylic polymer (b-1) include olefins such as ethylene and norbornene; vinyl acetate; styrene and the like.

As the polymer (b) having no energy ray-curable group, which is at least partially crosslinked by a cross-linking agent, for example, a polymer (b) in which the reactive functional group in the polymer (b) has reacted with the cross-linking agent Can be mentioned.
The reactive functional group may be appropriately selected depending on the type of the cross-linking agent and the like, and is not particularly limited. For example, when the cross-linking agent is a polyisocyanate compound, examples of the reactive functional group include a hydroxyl group, a carboxy group, an amino group and the like, and among these, a hydroxyl group having high reactivity with an isocyanate group is preferable. When the cross-linking agent is an epoxy-based compound, examples of the reactive functional group include a carboxy group, an amino group, an amide group and the like, and among these, a carboxy group having high reactivity with an epoxy group is preferable. .. However, the reactive functional group is preferably a group other than the carboxy group from the viewpoint of preventing corrosion of the work or the circuit of the workpiece.

Examples of the polymer (b) having the reactive functional group and not having the energy ray-curable group include those obtained by polymerizing at least the monomer having the reactive functional group. In the case of the acrylic polymer (b-1), one or both of the acrylic monomer and the non-acrylic monomer listed as the monomers constituting the acrylic polymer (b-1) having the reactive functional group. It 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, and in addition to this, the above-mentioned acrylic. Examples of the based monomer and the non-acrylic monomer obtained by polymerizing a monomer in which one or more hydrogen atoms are substituted with the reactive functional group can be mentioned.

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

The weight average molecular weight (Mw) of the polymer (b) having no energy ray-curable group is preferably 1000 to 2000000 from the viewpoint of improving the film-forming property of the composition (IV-1). More preferably, it is 100,000 to 1500,000. Here, the "weight average molecular weight" is as described above.

The polymer (b) having no energy ray-curable group contained in the composition (IV-1) and the film for forming an energy ray-curable protective film may be only one kind or two or more kinds. In the case of species or more, their combinations and ratios can be arbitrarily selected.

Examples of the composition (IV-1) include those containing either or both of the polymer (a1) and the compound (a2). When the composition (IV-1) contains the compound (a2), it preferably also contains a polymer (b) having no energy ray-curable group. In this case, the composition (a1) is further contained. It is also preferable to contain. Further, the composition (IV-1) does not contain the compound (a2), and may contain both the polymer (a1) and the polymer (b) having no energy ray-curable group. ..

When the composition (IV-1) contains the polymer (a1), the compound (a2), and the polymer (b) having no energy ray-curable group, the composition (IV-1) is described as described above. The content of the compound (a2) is preferably 10 to 400 parts by mass with respect to 100 parts by mass of the total content of the polymer (a1) and the polymer (b) having no energy ray-curable group. , 30 to 350 parts by mass, more preferably.

In the composition (IV-1), the ratio of the total content of the energy ray-curable component (a) and the polymer (b) having no energy ray-curable group to the total content of the components other than the solvent (that is, , The ratio of the total content of the energy ray-curable component (a) and the polymer (b) having no energy ray-curable group to the total mass of the film in the energy ray-curable protective film forming film). , 5 to 90% by mass, more preferably 10 to 80% by mass, and particularly preferably 20 to 70% by mass. When the ratio of the content of the energy ray-curable component is in such a range, the energy ray-curable property of the energy ray-curable protective film forming film becomes better.

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

The thermosetting component, filler, coupling agent, cross-linking agent, photopolymerization initiator, colorant and general-purpose additive in the composition (IV-1) are each thermoset in the composition (III-1). The same as the sex component (B), filler (D), coupling agent (E), cross-linking agent (F), photopolymerization initiator (H), colorant (I) and general-purpose additive (J) are listed. Be done.

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 an adhesive force to the adherend by heating. The strength of the protective film formed from the energy ray-curable protective film forming film is also improved.
Further, the energy ray-curable protective film forming film formed by using the composition (IV-1) containing the energy ray-curable component and the colorant is the thermosetting protective film forming described above. The same effect as when the film for use contains the colorant (I) is exhibited.

In the composition (IV-1), one type of the thermosetting component, the filler, the coupling agent, the cross-linking agent, the photopolymerization initiator, the colorant and the general-purpose additive may be used alone. Two or more types may be used in combination, and when two or more types are used in combination, the combination and ratio thereof can be arbitrarily selected.

The contents of the thermosetting component, the coupling agent, the cross-linking agent, the photopolymerization initiator, the colorant and the general-purpose additive in the composition (IV-1) may be appropriately adjusted according to the intended purpose and are 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, for example, 50% by mass or more and 80% by mass or less, and 55% by mass. It may be any of more than 80% by mass or less, 50% by mass or more and 70% by mass or less, and 55% by mass or more and 70% by mass or less. When the ratio is in such a range, the components are mutually contained between the energy ray-curable pressure-sensitive adhesive and the protective film forming film before the energy ray-curing. It is possible to suppress the transition to.

The composition (IV-1) is preferably further containing a solvent because its handleability is improved by dilution.
Examples of the solvent contained in the composition (IV-1) include the same solvents as those in the composition (III-1).
The solvent contained in the composition (IV-1) may be only one kind or two or more kinds.
The content of the solvent in the composition (IV-1) is not particularly limited, and may be appropriately selected depending on, for example, the type of component other than the solvent.

<Manufacturing method of composition for forming energy ray-curable protective film>
A composition for forming an energy ray-curable protective film such as the composition (IV-1) can be obtained by blending each component for forming the composition.
The composition for forming an energy ray-curable protective film can be produced by the same method as in the case of the pressure-sensitive adhesive composition described above, except that, for example, the types of compounding components are different.

(◎ Non-curable protective film forming film) A preferable non-curable protective film forming film includes, for example, a film containing a thermoplastic resin and a filler.

<Composition for forming a non-curable protective film (V-1)>
As a preferable non-curable protective film-forming composition, for example, the non-curable protective film-forming composition (V-1) containing the thermoplastic resin and the filler (in the present specification, simply "composition". (V-1) ”may be abbreviated).

[Thermoplastic resin]
The thermoplastic resin is not particularly limited.
More specifically, as the thermoplastic resin, for example, the acrylic resin, polyester, polyurethane, phenoxy resin, polybutene, polybutadiene, polystyrene and the like mentioned as the components contained in the above composition (III-1) are cured. Examples include those similar to non-sexual resins.

The thermoplastic resin contained in the composition (V-1) and the film for forming a non-curable protective film may be only one type, may be two or more types, and if there are two or more types, a combination and ratio thereof. Can be selected arbitrarily.

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

[Filler]
The non-curable protective film forming film containing the filler has the same effect as the thermosetting protective film forming film containing the filler (D).

The filler contained in the composition (V-1) and the non-curable protective film forming film is the same as the filler (D) contained in the composition (III-1) and the thermosetting protective film forming film. Things can be mentioned.

The filler contained in the composition (V-1) and the film for forming a non-curable protective film may be only one kind, two or more kinds, and when there are two or more kinds, the combination and ratio thereof are arbitrary. Can be selected.

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

The composition (V-1) may contain other components in addition to the thermoplastic resin and the filler, depending on the purpose.
The other components are not particularly limited and can be arbitrarily selected depending on the intended purpose.
For example, the non-curable protective film forming film (in other words, the protective film) formed by using the composition (V-1) containing the thermoplastic resin and the colorant is the thermosetting film described above. The protective film-forming film exhibits the same effect as when the colorant (I) is contained.

In the composition (V-1), one of the other components may be used alone, two or more of them may be used in combination, and when two or more of them are used in combination, the combination and ratio thereof shall be different. It can be selected arbitrarily.

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

The composition (V-1) is preferably further containing a solvent because its handleability is improved by dilution.
Examples of the solvent contained in the composition (V-1) include the same solvents as those in the above-mentioned composition (III-1).
The solvent contained in the composition (V-1) may be only one type or two or more types.
The content of the solvent in the composition (V-1) is not particularly limited, and may be appropriately selected depending on the type of component other than the solvent, for example.

<Manufacturing method of non-curable protective film forming composition>
A non-curable protective film forming composition such as the composition (V-1) can be obtained by blending each component for forming the composition.
The non-curable protective film forming composition can be produced, for example, by the same method as in the case of the pressure-sensitive adhesive composition described above, except that the types of compounding components are different.

◇ Method for manufacturing a composite sheet for forming a protective film The composite sheet for forming a protective film is laminated so that the above-mentioned layers have a corresponding positional relationship, and the shape of a part or all of the layers is adjusted as necessary. It can be manufactured. The method of forming each layer is as described above.

For example, when a pressure-sensitive adhesive layer is laminated on a base material when manufacturing a support sheet, the above-mentioned pressure-sensitive adhesive composition may be applied onto the base material and dried if necessary.
Further, the pressure-sensitive adhesive composition is applied onto the release film and dried as necessary to form a pressure-sensitive adhesive layer on the release film, and the exposed surface of the pressure-sensitive adhesive layer is used as one of the base materials. The pressure-sensitive adhesive layer can also be laminated on the base material by the method of bonding to the surface of the above. At this time, it is preferable that the pressure-sensitive adhesive composition is applied to the peel-treated surface of the release film.
Up to this point, the case of laminating the pressure-sensitive adhesive layer on the base material has been described as an example, but the above method can also be applied to, for example, the case of laminating the other layer on the base material.

On the other hand, for example, when a protective film-forming film is further laminated on the pressure-sensitive adhesive layer already laminated on the base material, the protective film-forming composition is applied on the pressure-sensitive adhesive layer to form a protective film. It is possible to directly form a forming film. Layers other than the protective film-forming film can also be laminated on the pressure-sensitive adhesive layer in the same manner by using the composition for forming this layer. In this way, a new layer (hereinafter, abbreviated as "second layer") is formed on any of the layers already laminated on the base material (hereinafter, abbreviated as "first layer"). When forming a continuous two-layer laminated structure (in other words, a laminated structure of the first layer and the second layer), a composition for forming the second layer is applied on the first layer. Then, a method of drying can be applied if necessary.
However, the second layer is formed in advance on the release film using the composition for forming the second layer, and the side of the formed second layer opposite to the side in contact with the release film. It is preferable to form a continuous two-layer laminated structure by laminating the exposed surface of the first layer with the exposed surface of the first layer. At this time, it is preferable that the composition is applied to the peeled surface of the peeling film. The release film may be removed if necessary after the laminated structure is formed.
Here, the case where the protective film forming film is laminated on the pressure-sensitive adhesive layer has been given as an example, but the target laminated structure may be arbitrary, for example, when the other layer is laminated on the pressure-sensitive adhesive layer. You can choose.

As described above, all the layers other than the base material constituting the protective film forming composite sheet can be laminated in advance by forming them on the release film and laminating them on the surface of the target layer, so that they can be laminated as needed. A layer for adopting such a process may be appropriately selected to produce a composite sheet for forming a protective film.

The protective film-forming composite sheet is usually stored in a state where a release film is attached to the surface of the outermost layer (for example, the protective film-forming film) on the opposite side of the support sheet. Therefore, a composition for forming a layer constituting the outermost layer, such as a composition for forming a protective film, is applied onto the release film (preferably the release-treated surface thereof) and dried if necessary. Then, a layer constituting the outermost layer is formed on the release film, and the remaining layers are laminated on the exposed surface on the side opposite to the side in contact with the release film of this layer by any of the above methods. However, by leaving the release film in a bonded state without removing it, a composite sheet for forming a protective film with a release film can be obtained.

◇ Manufacturing method of workpiece with protective film (How to use composite sheet for forming protective film)
The composite sheet for forming a protective film can be used for manufacturing the workpiece with a protective film.
As an example of a method for manufacturing a work piece with a protective film having a protective film at any part of the work piece, the protective film forming film in the protective film forming composite sheet is the object of the work. A sticking step of producing a laminated body in which the protective film forming composite sheet is provided on the work by sticking to a portion, and a sticking step of the protective film, which is performed as necessary after the sticking step. After the curing step of curing the forming film and the pasting step, the protective film forming composite sheet is subjected to the protective film forming composite sheet in the protective film forming composite sheet of the laminate or the cured product thereof. The work is processed after the printing step of printing on the protective film forming film or a cured product thereof by irradiating the support sheet with laser light from the outside on the support sheet side. As a result, it has a processing step of producing a work piece, and the protective film forming film after being attached to the work is made into a protective film without being cured, or is cured obtained by curing. A manufacturing method using an object as a protective film can be mentioned.

An example of a method for manufacturing a workpiece with a protective film when the work is a semiconductor wafer, that is, a semiconductor chip with a protective film is a method for manufacturing a semiconductor chip with a protective film having a protective film on the back surface of the semiconductor chip. By attaching the protective film-forming film in the protective film-forming composite sheet to the back surface of the semiconductor wafer, a laminate in which the protective film-forming composite sheet is provided on the back surface of the semiconductor wafer is produced. After the sticking step, the curing step of curing the protective film forming film, which is performed after the sticking step, and the sticking step, the protective film in the protective film forming composite sheet in the laminated body By irradiating the forming film or a cured product thereof with laser light from the outside on the support sheet side of the protective film forming composite sheet through the support sheet, the protective film forming film or the cured product thereof A printing step of printing on a film, and a division / cutting step of dividing the semiconductor wafer to produce a semiconductor chip and further cutting the protective film forming film or a cured product thereof. The protective film forming after being attached to the semiconductor wafer is provided with a pick-up step of pulling the semiconductor chip provided with the film for forming the protective film after cutting or a cured product thereof from the support sheet and picking it up. Examples thereof include a manufacturing method in which the film is used as a protective film without being cured, or the 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 as the work.

In the manufacturing method, by using the protective film forming composite sheet of the present embodiment described above, even when the laser beam having a short wavelength such as 266 nm is irradiated, the protective film forming composite sheet is contained. Can be printed well on the protective film forming film or a cured product thereof. Further, this print can be satisfactorily visually recognized through the support sheet from the outside on the support sheet side of the composite sheet for forming the protective film.

The manufacturing method includes a manufacturing method when the curing step is included (in the present specification, it may be referred to as "manufacturing method (1)") and a manufacturing method when the curing step is not provided (the present specification). In the above, it may be referred to as "manufacturing method (2)").
Hereinafter, these manufacturing methods will be sequentially described.

<< Manufacturing method (1) >>
The manufacturing method (1) is a method for manufacturing a work piece with a protective film, which is provided with a protective film at any part of the work piece, and is a film for forming a protective film in the composite sheet for forming the protective film. Is attached to a target portion of the work to prepare a laminated body in which the protective film forming composite sheet is provided (laminated) on the work, and after the application step, the protection After the curing step of curing the film-forming film and the pasting step, the protective film-forming composite sheet is applied to the protective film-forming composite sheet in the protective film-forming composite sheet of the laminate or the cured product thereof. The work is processed after the printing step of printing on the protective film forming film or the cured product thereof by irradiating the support sheet with laser light from the outside on the support sheet side of the above. By doing so, it has a processing step of producing a work processed product, and the cured product obtained by curing the protective film forming film after being attached to the work is used as a protective film.

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

<Attachment process>
In the pasting step, the protective film-forming composite sheet 101 from which the release film 15 has been 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. Is affixed to the back surface 9b of the semiconductor wafer 9. As a result, a laminated body 901 composed of the semiconductor wafer 9 and the protective film forming composite sheet 101 provided on the back surface 9b thereof is produced.

In the attachment step, the protective film forming film 13 may be softened by heating and attached to the semiconductor wafer 9.
Here, in the semiconductor wafer 9, the illustration of bumps and the like on the circuit forming surface 9a is omitted.
Further, reference numeral 13b is a surface of the protective film forming film 13 opposite to the first surface 13a (in other words, the pressure-sensitive adhesive layer 12 side) (in this specification, it may be referred to as “second surface”). Is shown.

The back surface of the semiconductor wafer 9 may be ground in order to obtain the desired value in its thickness. That is, the back surface 9b of the semiconductor wafer 9 may be a ground surface.

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

<Curing process>
After the pasting step, in the curing step, as shown in FIG. 3B, the protective film forming film 13 is cured.
Here, the case where the curing step is performed before the printing step is shown.
In the present embodiment, the cured product obtained by curing the protective film forming film 13 after being attached to the semiconductor wafer 9 is used as the protective film regardless of the presence or absence of cutting thereof.

By performing the curing step, the protective film forming composite sheet 101 becomes a protective film forming composite sheet 1011 in which the protective film forming film 13 becomes the cured product 13', and is provided on the semiconductor wafer 9 and its back surface 9b. A cured laminate 9011 is obtained, which is configured by comprising the protective film forming composite sheet 1011.
Reference numeral 13a'indicates 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'corresponds to the second surface 13b of the protective film forming film 13. The second surface of the cured product 13'is shown.

In the curing step, when the protective film forming film 13 is thermosetting, the cured product 13'is formed by heating the protective film forming film 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 via 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 at the time of thermosetting, and the illuminance and the amount of light of the energy rays at the time of energy ray curing are as described above.

<Printing process>
After the pasting step, in the printing step, as shown in FIG. 3C, for forming a protective film against the cured product 13'in the protective film forming composite sheet 1011 in the cured laminate 9011. The cured product 13'is printed by irradiating the laser beam L from the outside of the composite sheet 1011 on the support sheet 10 side through the support sheet 10. Printing (not shown) is applied to the second surface 13b'of the cured product 13'.

By performing the printing step, the protective film forming composite sheet 1011 becomes a protective film forming composite sheet 1012 having the printed cured product 13', and the protective film provided on the semiconductor wafer 9 and the back surface 9b thereof. A printed and cured laminate 9012 is obtained, which is configured with the forming composite sheet 1012.

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

<Division / 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 further, the cured product 13'is cut. To do.
A semiconductor chip with a protective film configured to include a semiconductor chip 9'and a cured product 130' after cutting provided on the back surface 9b'of the semiconductor chip 9'by performing a division / cutting step. A plurality of 91s are obtained. All of the plurality of semiconductor chips 91 with a protective film are aligned on one support sheet 10, and the semiconductor chips 91 with a protective film and the support sheet 10 form a group of semiconductor chips 910 with a protective film. It is configured.

Reference numeral 130a'indicates the first surface of the cured product 130'after cutting, which corresponds to the first surface 13a' of the cured product 13', and reference numeral 130b'is the second surface 13b of the cured product 13'. The second surface of the cured product 130'after cutting corresponding to'is shown.
Reference numeral 9a'indicates the circuit forming surface of the semiconductor chip 9'corresponding to the circuit forming surface 9a of the semiconductor wafer 9.

The semiconductor chip 9'by dividing the semiconductor wafer 9 (in other words, individualizing) can be manufactured by a known method.
As a method for dividing the semiconductor wafer 9, for example, blade dicing for dicing the semiconductor wafer 9 using a blade; laser dicing for dicing the semiconductor wafer 9 by laser irradiation; and dicing the semiconductor wafer 9 by spraying water containing an abrasive. Examples thereof include a method of cutting a semiconductor wafer such as water dicing. The cut may reach up to the pressure-sensitive adhesive layer 12 or up to the base material 11. In the case of up to the adhesive layer 12, cutting chips are less likely to be generated. In the case of up to the base material 11, the expandability at the time of expanding is improved.
When these methods are applied, for example, by dividing the semiconductor wafer 9 and cutting the cured product 13'at the same time, the semiconductor wafer 9 is divided and the cured product 13'is cut at once. You may go.

Examples of the method for dividing the semiconductor wafer 9 include methods other than the method for cutting the semiconductor wafer.
That is, in this method, first, a planned division portion is set inside the semiconductor wafer 9, and a laser beam is irradiated so as to focus on this focal point on the inside of the semiconductor wafer 9. Form a modified layer. Unlike other parts of the semiconductor wafer, the modified layer of the semiconductor wafer is denatured by irradiation with laser light, and its strength is weakened. Therefore, when a force is applied to the semiconductor wafer 9, cracks extending in both sides of the semiconductor wafer 9 are generated in the modified layer inside the semiconductor wafer 9, and serve as a starting point for dividing (cutting) the semiconductor wafer 9. Next, a force is applied to the semiconductor wafer 9 to divide the semiconductor wafer 9 at the site of the modified layer to produce a semiconductor chip. The method of dividing the semiconductor wafer 9 that involves 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 in a direction parallel to the surface thereof and applying a force. When the method of expanding the semiconductor wafer is applied in this way, 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. The division of the semiconductor wafer 9 and the cutting of the cured product 13'may be performed at once. It is preferable that the cured product 13'is cut by expanding at a low temperature of -20 to 5 ° C. or the like.

When the division of the semiconductor wafer 9 and the cutting of the cured product 13'are not performed at once, the cured product 13'can be separately cut by a known method in addition to the division of the semiconductor wafer 9. Good.

<Pickup process>
After the division / cutting step, in the pick-up step, as shown in FIG. 3 (e), a semiconductor chip 9'(semiconductor chip 91 with a protective film) having the cured product 130' after cutting is supported. Pull it away from the seat 10 and pick it up. Here, the direction of the pickup is indicated by an arrow I.

The semiconductor chip 91 with a protective film can be picked up by a known method. For example, as the separating means 8 for separating the semiconductor chip 91 with a protective film from the support sheet 10, a vacuum collet or the like can be mentioned. Here, only the pulling means 8 is not shown in cross section, and this is the same in the following similar figures.
From the above, the target semiconductor chip 91 with a protective film can be obtained.

In the semiconductor chip 91 with a protective film, which was the target of the printing process, including the picked-up one, the printing is clearly maintained on the second surface 130b'of the cured product 130' after cutting.

<Timing of curing process>
Up to this point, the case where the curing process is performed between the pasting process and the printing process has been described, but the timing at which the curing process is performed in the manufacturing method (1) is not limited to this. For example, in the manufacturing method (1), the curing step may be performed either between the printing step and the dividing / cutting step, between the dividing / cutting step and the picking step, or after the picking step.

When the curing step is performed after the sticking step and the printing step, in the printing step, the protective film is opposed to the protective film forming film 13 in the protective film forming composite sheet 101 in the laminated body 901 shown in FIG. 3 (a). Printing is performed on the protective film forming film 13 by irradiating the laser beam L from the outside on the support sheet 10 side of the forming composite sheet 101 through the support sheet 10. Printing (not shown) is applied to the second surface 13b of the protective film forming film 13.
The printing step in this case is the case of the printing step described above, except that the object to be irradiated with the laser beam L is not the cured product 13'of the protective film forming film 13 but the protective film forming film 13. Can be done in the same way as.

<Other processes>
The manufacturing method (1) may have other steps that do not correspond to any of these, in addition to the sticking step, the curing step, the printing step, the dividing / cutting step, and the picking step.
The types of the other steps and the timing at which the steps are performed 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 with a protective film, which is provided with a protective film at any part of the workpiece, and is a protective film forming film in the protective film forming composite sheet. Is attached to a target portion of the work to produce a laminated body in which the protective film forming composite sheet is provided on the work (laminated), and after the attaching step, the lamination is performed. The protective film-forming film in the protective film-forming composite sheet on the body is irradiated with laser light from the outside of the protective film-forming composite sheet on the support sheet side through the support sheet. It has a printing step of printing on a protective film forming film and a processing step of producing a work piece by processing the work after the printing step, and the protection after being attached to the work. Examples thereof include a manufacturing method in which a film-forming film is used as a protective film without being cured.
The manufacturing method (2) is the same as that of the manufacturing method (1), except that the protective film forming film after being attached to the work is used as the protective film as it is, regardless of the type of the work. It is the same and has the same effect as that of the manufacturing method (1).

Up to this point, the method for manufacturing the work piece with the protective film when the composite sheet 101 for forming the protective film shown in FIG. 1 is mainly described has been described, but the method for manufacturing the work piece with the protective film according to the present embodiment has been described. Is not limited to this.
For example, even if a material other than the protective film forming composite sheet 101 shown in FIG. 1 such as the protective film forming composite sheet shown in FIG. 2 is used, a workpiece with a protective film can be similarly manufactured by the above-mentioned manufacturing method. ..
When the composite sheet for forming a protective film of another embodiment is used, in the above-mentioned production method, an appropriate step is taken based on the difference in structure between this sheet and the composite sheet for forming a protective film 101. A work piece with a protective film may be manufactured by adding, changing, deleting, or the like.

◇ Manufacturing method of semiconductor device After obtaining a workpiece with a protective film by the above-mentioned manufacturing method, use this workpiece with a protective film, and depending on the type, use a known appropriate method to manufacture the semiconductor device. Can be manufactured. For example, when the workpiece with a protective film is a semiconductor chip with a protective film, the semiconductor chip with the protective film is flip-chip connected to the circuit surface of the substrate to form a semiconductor package, and this semiconductor package is used. , The target semiconductor device can be manufactured (not shown).

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

<Raw material for manufacturing resin>
The official names of the resin manufacturing raw materials, which are abbreviated in this example and the comparative example, are shown below.
MA: Methyl acrylate HEA: 2-Hydroxyethyl acrylate 2EHA: -2-ethylhexyl acrylate MOI: 2-Methylloyloxyethyl isocyanate BA: n-butyl acrylate GMA: Glycidyl methacrylate VAc: Vinyl acetate AA: HEMA acrylate : 2-Hydroxyethyl methacrylate

<Manufacturing raw material for protective film forming composition>
The raw materials used for producing the protective film forming composition 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 300,000, 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 800,000, glass) Transition temperature -28 ° C)
[Thermosetting component (B1)]
(B1) -1: Bisphenol A type epoxy resin ("jER828" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 184 to 194 g / eq)
(B1) -2: Bisphenol A type epoxy resin ("jER1055" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 800-900 g / eq)
(B1) -3: Dicyclopentadiene type epoxy resin ("Epiclon HP-7200HH" manufactured by DIC Corporation, epoxy equivalent 255-260 g / eq)
[Thermosetting agent (B2)]
(B2) -1: Thermally active latent epoxy resin curing agent dicyandiamide (manufactured by Mitsubishi Chemical Corporation, DICY7, active hydrogen amount 21 g / eq)
[Curing accelerator (C)]
(C) -1: 2-Phenyl-4,5-dihydroxymethylimidazole ("Curesol 2PHZ-PW" manufactured by Shikoku Chemicals Corporation)
[Filler (D)]
(D) -1: Silica filler (fused quartz filler, average particle size 8 μm)
[Coupling agent (E)]
(E) -1: Silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., KBM503)
[Crosslinking agent (F)]
(F) -1: Isocyanate-based cross-linking agent (Tosoh's "Coronate L", trimethylolpropane trimerized isocyanate trimer adduct)
[Colorant (I)]
(I) -1: 32 parts by mass of phthalocyanine blue dye (Pigment Blue 15: 3), 18 parts by mass of isoindolinone yellow dye (Pigment Yellow 139), and 50 parts by mass of anthraquinone red dye (Pigment Red 177). A pigment obtained by mixing and pigmenting so that the total amount of the above three types of 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 (“A-9300-1CL” manufactured by Shin-Nakamura Chemical Industry Co., Ltd., a trifunctional UV curable compound)

[Example 1]
<< Manufacturing of support sheet >>
<Manufacturing of adhesive resin (I-2a)>
An acrylic polymer having a weight average molecular weight of 600,000, which is a copolymer of 2EHA (42 parts by mass), VAc (40 parts by mass), and HEA (18 parts by mass), is added to MOI (in the acrylic polymer). The total number of moles of isocyanate groups in MOI is 0.8 times the total number of moles of hydroxyl groups derived from HEA), and the addition reaction is carried out at 50 ° C. for 48 hours in an air stream. , The target adhesive resin (I-2a) -1 was obtained.
Hereinafter, the acrylic polymer may be referred to as "adhesive resin (I-1a) -1".

<Manufacturing of Adhesive Composition (I-2)>
Adhesive resin (I-2a) -1 (100 parts by mass), hexamethylene diisocyanate-based cross-linking agent ("Coronate L" manufactured by Toso Co., Ltd.) (0.21 parts by mass), and photopolymerization initiator (BASF Co., Ltd. "Irgacure") 127 ”, containing 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] -phenyl} -2-methyl-propane-1-one) (3 parts by mass) Further, an energy ray-curable pressure-sensitive adhesive composition (I-2) -1 containing ethyl acetate as a solvent and having a total concentration of all components other than the solvent of 30% by mass was prepared. The contents of the components other than ethyl acetate shown here are all the contents of the target product containing no solvent.

<Manufacturing of support sheet>
A release film (“SP-PET38131” manufactured by Lintec Corporation, thickness 38 μm) in which one side of a polyethylene terephthalate film was peeled by a silicone treatment was used, and the pressure-sensitive adhesive composition obtained above was used on the peeled surface. I-2) -1 was applied and dried by heating 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%. The gel fraction of the pressure-sensitive adhesive layer is a value measured by the method described above. This also applies to the following Examples and Comparative Examples.
Next, by adhering a polypropylene film (1) (thickness 80 μm, colorless) as a base material to the exposed surface of the pressure-sensitive adhesive layer, the base material, the pressure-sensitive adhesive layer, and the release film have these thicknesses in this order. A laminated sheet constructed by being laminated in the direction, that is, a support sheet with a release film was manufactured.

<< Manufacture of protective film forming film >>
<Manufacturing of composition for forming protective film (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) dissolved in a mixed solvent of methyl ethyl ketone, toluene and ethyl acetate. Alternatively, the composition was dispersed and stirred at 23 ° C. to obtain a thermosetting protective film-forming composition (III-1) -1 having a total concentration of all components other than the solvent of 50% by mass. The blending amounts of the components other than the mixed solvent shown here are all the blending amounts of the target product containing no solvent.
The content of the filler in the thermosetting protective film forming composition excluding the solvent was 54.1% by mass. The Tg of the protective film forming composition was 23.5 ° C.

<Manufacturing of protective film forming film>
A release film (second release film, "SP-PET38131" manufactured by Lintec Corporation, thickness 38 μm) in which one side of a polyethylene terephthalate film was peeled by a silicone treatment was used, and the peeled surface was obtained as described above. The protective film-forming composition (III-1) -1 was applied and dried at 100 ° C. for 2 minutes to produce a thermosetting protective film-forming film having a thickness of 25 μm.
The loss elastic modulus E ″ of the protective film forming film was 51.6 MPa.

Further, the exposed surface of the obtained protective film forming film on the side not provided with the second release film is subjected to a release treatment of the release film (first release film, "SP-PET38131" manufactured by Lintec Co., Ltd., thickness 38 μm). By laminating the surfaces, a protective film forming film, a first release film provided on one surface of the protective film forming film, and a second release film provided on the other surface of the protective film forming film. A laminated film composed of a release film and a release film was obtained.

<< Manufacturing of composite sheet for forming protective film >>
The release film was removed from the support sheet obtained above. In addition, the first release film was removed from the laminated film obtained above. Then, by adhering 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 base material and the adhesive are adhered. A protective film-forming composite sheet was produced in which the agent layer, the protective film-forming film, and the second release film were laminated in this order in this order of thickness.

<< Evaluation of composite sheet for forming protective film >>
Using the above-mentioned composite sheet for forming a protective film, an 8-inch mirror wafer and a protective film forming film were bonded together. The obtained laminate of the 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 allowed to stand until the temperature reached room temperature.
After that, the surface of the wafer is suction-fixed to the suction table, the end of the support sheet is held by an arm, and a peel test is performed at the interface between the protective film and the support sheet at a peel angle of 180 ° and a peel speed (300 mm / min). , The peelability at the interface between the protective film and the support sheet was evaluated according to the following criteria.
A: It was possible to peel off at the interface between the protective film and the support sheet without any problem.
B: Peeling was possible at the interface between the protective film and the support sheet, but there was catching (zipping) during the peeling.
C: The interface between the protective film and the support sheet could not be peeled off, and the interface between the wafer and the protective film was peeled off.

<< Manufacture and evaluation of protective film forming film and protective film forming composite sheet >>
[Example 2]
In the production of the protective film forming composition, the same method as in Example 1 was used except that the polymer component (A) -1 was used in an amount of 29.6 parts by mass and the filler (D) -1 was used in an amount of 50 parts by mass. , A film for forming a protective film and a composite sheet for forming a protective film were produced and evaluated.
The loss elastic modulus E ″ of the protective film forming film was 11.0 MPa.
The content of the filler in the thermosetting protective film forming composition excluding the solvent was 50.0% by mass. The Tg of the protective film forming composition was 13.0 ° C.
The results are shown in Table 1.

[Example 3]
When producing the protective film forming composition, 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 the filler (19.0 parts by mass) is used. A support sheet, a protective film-forming film, and a protective film-forming composite sheet were produced and evaluated in the same manner as in Example 1 except that 60.6 parts by mass of D) -1 was used.
The loss elastic modulus E ″ of the protective film forming film was 2.2 MPa.
The content of the filler in the thermosetting protective film forming composition excluding the solvent was 60.6% by mass. The Tg of the protective film forming composition was 2.2 ° C.
The results are shown in Table 1.

[Example 4]
When producing the protective film forming composition, 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 the filler (25.5 parts by mass) is used. A protective film-forming film and a protective film-forming composite sheet were produced and evaluated in the same manner as in Example 1 except that 54.1 parts by mass of D) -1 was used.
The loss elastic modulus E ″ of the protective film forming film was 1.3 MPa.
The content of the filler in the thermosetting protective film forming composition excluding the solvent was 54.1% by mass. The Tg of the protective film forming composition was 1.7 ° C.
The results are shown in Table 1.

[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) dissolved in a mixed solvent of methyl ethyl ketone, toluene and ethyl acetate. Alternatively, the composition was dispersed and stirred at 23 ° C. to obtain a thermosetting protective film-forming composition (III-1) -1 having a total concentration of all components other than the solvent of 50% by mass. The blending amounts of the components other than the mixed solvent shown here are all the blending amounts of the target product containing no solvent.
The content of the filler in the thermosetting protective film-forming composition excluding the solvent was 40.0% by mass. The Tg of the protective film forming composition was 16.5 ° C.
Next, using the protective film-forming composition, a protective film-forming film and a protective film-forming composite sheet were produced and evaluated in the same manner as in Example 1.
The loss elastic modulus E ″ of the protective film forming film was 18.4 MPa.
The results are shown in Table 1.

[Example 6]
During the production of the support sheet, the energy ray-curable pressure-sensitive adhesive composition (I-2) -2 was produced by the method shown below instead of the energy ray-curable pressure-sensitive adhesive composition (I-2) -1. The support sheet, the protective film forming film, and the protective film forming composite sheet were obtained in the same manner as in Example 1 except that the thickness of the pressure-sensitive adhesive layer was changed from 5 μm to 10 μm. Was manufactured and evaluated. The gel fraction of the pressure-sensitive adhesive layer was 50%. The loss elastic modulus E ″ of the protective film forming film was 51.6 MPa.
The results are shown in Table 1.

<Manufacturing of adhesive resin (I-2a)>
An acrylic polymer (100 parts by mass) having a weight average molecular weight of 300,000, which is a copolymer of 2EHA (21 parts by mass), VAc (76 parts by mass), AA (1 part by mass), and HEMA (2 parts by mass). (Parts), bifunctional and hexafunctional urethane acrylate mixture (72 parts by mass), hexamethylene diisocyanate-based cross-linking agent (“Coronate L” manufactured by Toso Co., Ltd.) (3 parts by mass), photopolymerization initiator (BASF Co., Ltd. “Irgacure 127”) , 2-Hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] -phenyl} -2-methyl-propane-1-one) (3 parts by mass) is mixed. , The target adhesive resin (I-2a) -2 was obtained by adjusting the concentration to 30% with ethyl acetate.

<Manufacture of Adhesive Composition (I-2) -2>
Adhesive resin (I-2a) -2 (100 parts by mass), hexamethylene diisocyanate-based cross-linking agent ("Coronate L" manufactured by Toso Co., Ltd.) (3 parts by mass), and photopolymerization initiator (BASF "Irgacure 127") , 2-Hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] -phenyl} -2-methyl-propane-1-one) (3 parts by mass). Further, an energy ray-curable pressure-sensitive adhesive composition (I-2) -2 containing ethyl acetate as a solvent and having a total concentration of all components other than the solvent of 30% by mass was prepared. The contents of the components other than ethyl acetate shown here are all the contents of the target product containing no solvent.
The content of the filler in the thermosetting protective film forming composition excluding the solvent was 54.1% by mass. The Tg of the protective film forming composition was 23.5 ° C.
The results are shown in Table 1.

[Example 7]
In the same method as in Example 6, except that the polymer component (A) -1 is used in an amount of 29.6 parts by mass and the filler (D) -1 is used in an amount of 50 parts by mass when the composition for forming a protective film is produced. A film for forming a protective film and a composite sheet for forming a protective film were produced and evaluated.
The loss elastic modulus E ″ of the protective film forming film was 11.0 MPa.
The content of the filler in the thermosetting protective film forming composition excluding the solvent was 50.0% by mass. The Tg of the protective film forming composition was 13.0 ° C.
The results are shown in Table 1.

[Example 8]
Same as in Example 5 except that the pressure-sensitive adhesive composition (I-2) -2 is used instead of the energy ray-curable pressure-sensitive adhesive composition (I-2) -1 when the support sheet is manufactured. By the method, a protective film forming film and a protective film forming composite sheet were produced and evaluated.
The loss elastic modulus E ″ of the protective film forming film was 18.4 MPa.
The content of the filler in the thermosetting protective film-forming composition excluding the solvent was 40.0% by mass. The Tg of the protective film forming composition was 16.5 ° C.
The results are shown in Table 1.

[Example 9]
<Manufacturing of composition for forming protective film (IV-1)>
Polymer component (A) -1 (27.07 parts by mass), energy ray-curable resin (G) -1 (10.0 parts by mass), cross-linking agent (F) -1 (0.77 parts by mass), light Polymerization initiator ((BASF "Irgacure 369", 2- (dimethylamino) -1- (4-morpholinophenyl) -2-benzyl-1-butanone) (0.6 parts by mass), filler (D) -1 (56.65 parts by mass), coupling agent (E) -1 (0.4 parts by mass), and colorant (I) -1 (4.5 parts by mass) of methyl ethyl ketone, toluene and ethyl acetate. Composition for forming an energy ray-curable protective film (III-1) -1 in which the total concentration of all components other than the solvent is 50% by mass by dissolving or dispersing in a mixed solvent and stirring at 23 ° C. The amounts of the components other than the mixed solvent shown here are all the amounts of the target product containing no solvent.
The content of the filler in the composition for forming an energy ray-curable protective film excluding the solvent was 56.7% by mass. The Tg of the protective film forming composition was 6.2 ° C.

<Manufacturing of protective film forming film>
A release film (second release film, "SP-PET38131" manufactured by Lintec Corporation, thickness 38 μm) in which one side of a polyethylene terephthalate film was peeled by a silicone treatment was used, and the peeled surface was obtained as described above. The protective film-forming composition (III-1) -1 was applied and dried at 100 ° C. for 2 minutes to produce an energy ray-curable protective film-forming film having a thickness of 25 μm.
The loss elastic modulus E ″ of the protective film forming film was 5.8 MPa.

Further, the exposed surface of the obtained protective film forming film on the side not provided with the second release film is subjected to a release treatment of the release film (first release film, "SP-PET38131" manufactured by Lintec Co., Ltd., thickness 38 μm). By laminating the surfaces, a protective film forming film, a first release film provided on one surface of the protective film forming film, and a second release film provided on the other surface of the protective film forming film. A laminated film composed of a release film and a release film was obtained.

<< Manufacturing of composite sheet for forming protective film >>
The release film was removed from the support sheet obtained by the same method as in Example 1. In addition, the first release film was removed from the laminated film obtained above. Then, by adhering 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 base material and the adhesive are adhered. A protective film-forming composite sheet was produced in which the agent layer, the protective film-forming film, and the second release film were laminated in this order in this order of thickness.
Next, instead of heating at 130 ° C. for 2 hours to cure, light with a wavelength of 365 nm is irradiated three times under the conditions of ^{an illuminance of 215 mW / cm 2} and a light intensity of 187 mJ / cm ^{2 to cure.} The composite sheet for forming a protective film was evaluated by the same method.
The results are shown in Table 1.

[Comparative Example 1]
When producing the protective film forming composition, 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 the filler (19.0 parts by mass) is used. A protective film-forming film and a protective film-forming composite sheet were produced and evaluated in the same manner as in Example 6 except that 60.6 parts by mass of D) -1 was used.
The loss elastic modulus E ″ of the protective film forming film was 2.2 MPa.
The content of the filler in the thermosetting protective film forming composition excluding the solvent was 60.6% by mass. The Tg of the protective film forming composition was 2.2 ° C.
The results are shown in Table 1.

[Comparative Example 2]
When producing the protective film forming composition, 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 the filler (25.5 parts by mass) is used. A protective film-forming film and a protective film-forming composite sheet were produced and evaluated in the same manner as in Example 6 except that 54.1 parts by mass of D) -1 was used.
The loss elastic modulus E ″ of the protective film forming film was 1.3 MPa.
The content of the filler in the thermosetting protective film forming composition excluding the solvent was 54.1% by mass. The Tg of the protective film forming composition was 1.7 ° C.
The results are shown in Table 1.

As is clear from the above results, in all of Examples 1 to 5 and 9, the gel fraction of the adhesive of the support sheet before UV curing was 90%, and the peelability evaluation of the composite sheet for forming the protective film was evaluated. Is A, and it could be smoothly peeled off at the interface between the support sheet and the protective film forming film.

In Examples 6 to 8, the gel fraction of the adhesive on the support sheet before UV curing was 50%, but the Tg of the protective film forming film was 3 ° C. or higher, and the protective film was formed. The peelability evaluation of the composite sheet was A or B. Although the peeling evaluation was slightly inferior in Example 8, any of the protective film-forming composite sheets could be peeled off at the interface between the support sheet and the protective film-forming film.

On the other hand, in each of the composite sheets for forming a protective film of Comparative Examples 1 and 2, the gel fraction of the adhesive of the support sheet before UV curing was 50%, and the Tg of the protective film forming film was 3. It was below ° C. Further, the loss elastic modulus E ″ of the protective film forming film at 23 ° C. 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, but was peeled off at the interface between the protective film-forming film and the adherend.

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

101, 102 ... Protective film forming composite sheet, 1011 ... Protective film forming composite sheet with cured protective film forming film, 1012 ... Protective film forming film cured and printed protection Composite sheet for film formation, 10 ... Support sheet, 10a ... One surface (first surface) of support sheet, 13, 23 ... Protective film forming film, 13'... Protective film (protection) Cured product of film forming film), 130'... Protective film after cutting (cured product of protective film forming film after cutting), 9 ... Semiconductor wafer, 9a ... Circuit forming surface of semiconductor wafer , 9b ... Back surface of semiconductor wafer, 9'... Semiconductor chip, L ... Laser light

Claims (5)

A base material is provided, and an energy ray-curable pressure-sensitive adhesive layer and a protective film-forming film are laminated in this order on one surface of the base material in contact with each other.
A composite sheet for forming a protective film, wherein the gel content of the pressure-sensitive adhesive layer is 80% or more. A base material is provided, and an energy ray-curable pressure-sensitive adhesive layer and a protective film-forming film are laminated in this order on one surface of the base material in contact with each other.
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, wherein the glass transition temperature of the film for forming a protective film is 3 ° C. or higher. The composite sheet for forming a protective film according to claim 1, wherein the glass transition temperature of the film for forming a protective film is 3 ° C. or higher. The composite sheet for forming a protective film according to any one of claims 1 to 3, wherein the elastic modulus for forming the protective film at 23 ° C. is 3 MPa or more. The protective film forming film contains a filler (D) and contains
The method according to any one of claims 1 to 4, wherein 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 50% by mass or more. The composite sheet for forming a protective film according to the above.

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