TW201731996A - Composite film for forming a protective film - Google Patents

Abstract

A composite sheet for forming a protective film, comprising a film for forming a protective film on one surface of the support sheet, and a coating layer on a surface of the support sheet opposite to the side including the film for forming a protective film; In the composite sheet for forming a protective film, the measured value of the haze from the side of the coating layer is 47% or less.

Description

Composite film for forming a protective film

The present invention relates to a composite sheet for forming a protective film for forming a protective film on the back surface of a semiconductor wafer.

The present application claims priority based on Japanese Patent Application No. 2016-042691, filed on Jan.

In recent years, there has been a fabrication of a semiconductor device using a mounting method called a so-called face down method. The face-down method is a semiconductor wafer having electrodes such as bumps on a circuit surface, and the electrodes are bonded to the substrate. Therefore, there is a case where the back surface on the opposite side to the circuit surface in the wafer is exposed.

A resin film made of an organic material is formed as a protective film on the back surface of the exposed wafer, and is incorporated in a semiconductor device in the form of a semiconductor wafer with a protective film. The protective film is used in order to prevent cracking of the wafer after the cutting step or packaging.

The protective film is formed by using a composite film for forming a protective film having a film for forming a protective film on a support sheet. The support sheet is, for example, a resin substrate, a laminate structure such as a substrate or an adhesive layer, or a surface layer of a protective film forming film or an adhesive layer of the substrate. The situation. In the composite sheet for forming a protective film, in addition to the protective film forming ability, the support sheet can function as a dicing sheet, and can be formed by integrating a film for forming a protective film and a dicing sheet.

The aforementioned substrate before the processing used for the support sheet usually has a concavo-convex shape on one side or both sides. The reason for this is that if the substrate is not wound, the substrate is wound up to form a roll, and the contact surfaces of the substrates adhere to each other and block, which makes it difficult to use. If at least one of the contact faces of the substrates has an uneven shape, the area of the contact faces is reduced, and thus the adhesion is suppressed.

A conventional composite sheet for forming a protective film having a substrate having such an uneven surface has a configuration shown in Fig. 4 as it is. Fig. 4 is a cross-sectional view schematically showing an example of a conventional composite sheet for forming a protective film. In addition, in the drawings used in the following description, for example, in order to make the characteristics of the composite sheet for forming a protective film easy to understand, for the sake of convenience, a part which becomes a main part is enlarged, and each constituent element The dimensional ratio and the like are not limited to the same as the actual ones.

The conventional composite film 9 for forming a protective film shown here is provided with a film 13 for forming a protective film on the support sheet 90, and the support sheet 90 includes a laminated structure of the substrate 91 and the adhesive layer 12, and an adhesive agent. The layer 12 is provided with a film 13 for forming a protective film. The film 13 for forming a protective film is cured to form a protective film. Further, the protective film forming composite sheet 9 further includes a release film 15 on the protective film forming film 13, and the release film 15 is removed when the protective film forming composite sheet 9 is used. In the composite sheet 9 for forming a protective film, the surface (back surface) 90b on the side opposite to the surface (surface) 90a of the support sheet forming film 13 is an uneven surface, that is, in the substrate 91. The surface (back surface) 91b on the opposite side to the surface (surface) 91a of the adhesive layer 12 is an uneven surface. In the composite sheet 9 for forming a protective film, the back surface 91b of the substrate 91 is made to have an uneven surface, and when it is wound up to form a roll, the exposed surface (surface) of the back surface 91b of the substrate 91 and the release film 15 is suppressed. The attachment of 15a suppresses the adhesion of the back surface 91b of the substrate 91 to the exposed surface (surface) 15a of the release film 15.

On the other hand, in the composite sheet for forming a protective film, the surface of the protective sheet formed of the film for forming a protective film is printed by irradiating laser light (hereinafter, referred to as "laser column" The situation of the "print" situation. The laser print is irradiated from the side opposite to the side on which the protective film is formed from the support sheet. In this case, for example, in the case of the composite sheet 9 for forming a protective film, the protective film is irradiated through the support sheet 90 from the back surface 91b side of the substrate 91. Since the back surface 91b of the substrate 91 is an uneven surface, the light is diffused and reflected there, and there is a problem that the laser printing becomes unclear.

A composite sheet for forming a protective film having the configuration shown in Fig. 5 is known as a composite sheet for forming a protective film which can prevent such diffused reflection of light (see, for example, Patent Document 1).

Fig. 5 is a cross-sectional view schematically showing another example of a conventional composite sheet for forming a protective film.

The composite sheet 8 for forming a protective film shown in the prior art is provided with a film 13 for forming a protective film on the support sheet 80 in the same manner as the composite sheet 9 for forming a protective film, and the support sheet 80 is made of a substrate 81 and an adhesive. The laminated structure of the layer 12 is formed, and the film 13 for forming a protective film is provided on the adhesive layer 12. Among them, in the support sheet 80, the arrangement of the uneven surface of the substrate 81 is opposite to the substrate 91 in the support sheet 90. In the composite sheet 8 for forming a protective film, the surface (surface) 81a of the base material 81 having the adhesive layer 12 is an uneven surface, and the surface (back surface) 81b of the base material 81 opposite to the surface 81a is smoothed. surface. The base material 81, the protective film forming film 13, and the release film 15 in the support sheet 80 are the same as the base material 91, the protective film forming film 13, and the release film 15 in the support sheet 90, respectively.

However, in the case of the composite sheet 8 for forming a protective film, the back surface 81b of the base material 81 is a smooth surface, that is, the side opposite to the surface (surface) 80a of the support sheet 80 having the adhesive layer 12 (back surface) ) 80b becomes smooth When the composite sheet 8 for forming a protective film is wound up to form a roll, the adhesion of the back surface 81b of the base material 81 to the exposed surface (surface) 15a of the release film 15 cannot be suppressed, that is, the substrate 81 cannot be suppressed. The back surface 81b is adhered to the exposed surface (surface) 15a of the release film 15. When the adhesion occurs, the protective film forming composite sheet 8 is wrinkled, or the release film 15 is peeled off from the protective film forming film 13 when the protective film forming composite sheet 8 is taken out from the roll. Further, on the surface 81a of the substrate 81, the adhesive layer 12 needs to have a sufficient thickness to eliminate the shape of the unevenness. When the thickness is insufficient, the uneven shape of the base material 81 is reflected, and the surface (back surface) 13b on the side of the support sheet 80 of the film for forming a protective film 13 has an uneven shape, and the film 13 for forming a protective film is provided. The laser printing performed on the side of the support sheet side of the formed protective film becomes unclear.

[Previous Technical Literature]

[Patent Literature]

Patent Document 1: Japanese Patent No. 5432853.

Thus, the conventional case is that there is no composite sheet for forming a protective film which can simultaneously suppress the adhesion and clear the laser print of the protective film.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a composite sheet for forming a protective film for forming a protective layer on the back surface of a semiconductor wafer. Membrane, and adhesion can be suppressed, and the protective film can be clearly laser printed.

One aspect of the invention is as follows.

(1) In the embodiment of the present invention, the composite sheet for forming a protective film is provided with a film for forming a protective film on one surface of the support sheet, and the protective film is formed on the support sheet. The coating layer is provided on the surface on the opposite side to the side of the film, and the measured value of the haze from the side of the coating layer in the composite sheet for forming a protective film is 47% or less.

(2) In the composite sheet for forming a protective film according to the above (1), the composite sheet for forming a protective film which is further provided on the film for forming a protective film may be used, and may be measured by the following method. The peeling force of the release film is 10 mN/50 mm or less.

(Method for measuring peeling force of peeling film)

The composite sheet for forming a protective film which has a release film and a width of 50 mm and a length of 100 mm on the film for forming a protective film, wherein the coating layers are all oriented in the same direction and the total thickness of the coating layer is 10 μm to 60 μm. In the manner of laminating a plurality of sheets, the first outermost layer is a coating layer, and the second outermost layer is a laminate of a release film, and the laminate is applied with a force of 980.665 mN in the direction of lamination of the composite sheet for forming a protective film. After standing at 40 ° C for 3 days, it will be the most in the above-mentioned stacking direction. The release film of the coating layer of the first outermost layer was peeled off from the adjacent coating layer at a peeling speed of 300 mm/min and a peeling angle of 180°, and the peeling force at this time was measured.

(3) In the composite sheet for forming a protective film according to the above aspect (1) or (2), the support sheet may be formed by laminating a base material and an adhesive, and the composite sheet for forming a protective film may be sequentially The coating layer, the substrate, the adhesive layer, and the film for forming a protective film are laminated.

(4) In the composite sheet for forming a protective film of the above (3), the pressure-sensitive adhesive layer may be an energy ray-curable or non-energy-curable adhesive layer.

In the composite sheet for forming a protective film according to any one of the above aspects, the film for forming a protective film may be a film for forming a protective film which is thermosetting or energy ray curable.

According to the present invention, there is provided a composite sheet for forming a protective film for forming a protective film on the back surface of a semiconductor wafer, and suppressing adhesion, and performing laser printing on the protective film clearly.

1, 2‧‧‧Composite film for protective film formation

8‧‧‧Composite film for protective film formation

9‧‧‧Composite film for protective film formation

10‧‧‧Support film

10a‧‧‧Surface of the support piece

10b‧‧‧Back of the support piece

11‧‧‧Substrate

11a‧‧‧ Surface of the substrate

11b‧‧‧The back of the substrate

12‧‧‧Adhesive layer

12a‧‧‧ Surface of the adhesive layer

13, 23‧‧‧film for protective film formation

13a, 23a‧‧‧ Surface of film for protective film formation

14‧‧‧ Coating layer

14a‧‧‧Surface of the coating layer

14b‧‧‧Back of the coating layer

15‧‧‧Release film

15a‧‧‧ peeling film surface

16‧‧‧Layer layer for fixtures

16a‧‧‧ Surface of the adhesive layer for the fixture

80‧‧‧Support film

80a‧‧‧Surface of the support piece

80b‧‧‧back of the support piece

81‧‧‧Substrate

81a‧‧‧ Surface of the substrate

81b‧‧‧Back of the substrate

90‧‧‧Support film

90a‧‧‧Surface of the support piece

90b‧‧‧back of the support piece

91‧‧‧Substrate

91a‧‧‧ Surface of the substrate

91b‧‧‧Back of the substrate

121‧‧‧The surrounding department

122‧‧‧ peripherals

W ₁ ‧‧‧Width

W ₂ ‧‧‧ spacing

d ₁ ‧‧‧diameter

d ₂ ‧‧‧diameter

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

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

Fig. 3 is a plan view showing a composite sheet for forming a protective film produced in the examples.

Fig. 4 is a cross-sectional view schematically showing an example of a conventional composite sheet for forming a protective film.

Fig. 5 is a cross-sectional view schematically showing another example of a conventional composite sheet for forming a protective film.

◎ Composite film for protective film formation

The composite sheet for forming a protective film of the present embodiment is provided with a film for forming a protective film on one surface of the support sheet, and is coated on the surface of the support sheet opposite to the side including the film for forming a protective film. The measured value of the haze from the side of the coating layer in the composite sheet for forming a protective film was 47% or less.

In the composite sheet for forming a protective film, the measured value of the haze from the side of the coating layer is within a specific range as described above, and the protective film is cured from the coating layer after curing the film for forming a protective film. When the side is irradiated with the laser light, the scattering of the laser light is suppressed, so that the protective film can be clearly laser printed.

In addition, the composite sheet for forming a protective film has the coating layer having slipperiness and antistatic property, and when it is wound up to form a roll, adhesion is suppressed.

In the above-mentioned composite film for forming a protective film, the film for forming a protective film is cured by heating or irradiation with an energy ray to form a protective film, and the laminate structure of the support sheet and the protective film is maintained. It is also called a composite sheet for forming a protective film. In the case of the composite sheet for forming a protective film, when the support sheet is a laminated structure of a base material and an adhesive layer, the adhesive layer is cured to maintain the cured product of the base material and the adhesive layer. The laminated structure of the film for forming a protective film or the protective film is also referred to as a composite sheet for forming a protective film.

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

The composite sheet 1 for forming a protective film shown here is provided with a film 13 for forming a protective film on one surface 10a of the support sheet 10, and a coating layer 14 is provided on the other surface (back surface) 10b of the support sheet 10. to make. Further, the support sheet 10 is formed by laminating the substrate 11 and the adhesive layer 12, and has an adhesive layer 12 on one surface 11a of the substrate 11, and a coating on the other surface (back surface) 11b of the substrate 11. The cloth layer 14 is provided with a film 13 for forming a protective film on the adhesive layer 12. In addition, the protective film forming composite sheet 1 further includes a release film 15 on the protective film forming film 13, and the release film 15 is removed when the protective film forming composite sheet 1 is used. The film 13 for forming a protective film is cured to form a protective film.

In the composite sheet 1 for forming a protective film, the adhesive layer 12 is laminated on the surface 11a of the substrate 11, and the film 13 for forming a protective film is laminated. A portion of the surface 12a of the adhesive layer 12. Further, in the surface 12a of the adhesive layer 12, the exposed surface of the film 13 for forming the protective film is not laminated, and the release film 15 is laminated on the surface 13a (upper surface and side surface) of the film 13 for forming a protective film.

Further, a void portion may be present between the release film 15 and the surface 12a of the adhesive layer 12 or the surface 13a of the protective film formation film 13. For example, the side surface of the film 13 for forming a protective film or the vicinity of the film 13 for forming a protective film in the surface 12a of the adhesive layer 12 is likely to generate the above-mentioned void portion.

In the composite sheet 1 for forming a protective film, the haze measured from the direction of the surface (back surface) 14b of the coating layer 14 opposite to the surface (surface) 14a of the support sheet 10 (substrate 11) becomes 47% or less. Thereby, the protective film can be clearly subjected to laser printing.

In addition, in the present invention, "haze" means a value measured in accordance with JIS K 7136 unless otherwise specified.

In addition, when the composite sheet 1 for forming a protective film is provided with the coating layer 14 and is wound into a roll, the exposed surface (surface) 15a of the back surface 11b of the substrate 11 and the release film 15 is also suppressed. The adhesion, that is, the adhesion of the aforementioned back surface 11b of the substrate 11 to the exposed surface (surface) 15a of the release film 15 is suppressed.

In the composite sheet 1 for forming a protective film, the surface of the support sheet 10 opposite to the surface (surface) 10a including the film 13 for forming a protective film (back) Here, the surface 10b is an uneven surface having a low degree of smoothness, that is, a surface (back surface) 11b on the side opposite to the surface (surface) 11a of the substrate 11 having the adhesive layer 12 is a rough surface having a low smoothness. But it can also be a smooth surface. When a protective film (not shown) formed of the film 13 for forming a protective film is subjected to laser printing, the surface of the protective film on the side of the support sheet 10 is irradiated with laser light from the side of the coating layer 14. At this time, when the back surface 10b of the support sheet 10 (the back surface 11b of the base material 11) is either an uneven surface or a smooth surface, since the coating layer 14 covers the surface, the contact layer 14 is in contact with each other. The surface (back surface) 14b on the opposite side (surface) 14a of the support sheet 10 (substrate 11) has a high smoothness and a small surface roughness Ra, whereby the diffuse reflection of the laser light on the coating layer 14 is suppressed. The protective film can be clearly laser printed.

In addition, in this specification, the "surface roughness Ra" means the arithmetic mean roughness prescribed by JIS B0601:2001 unless otherwise specified.

In the composite sheet 1 for forming a protective film, the surface 11a of the substrate 11 is a smooth surface here, but may be an uneven surface having a low smoothness. In the case where the void portion is formed between the surface 11a of the substrate 11 and the adhesive layer as described below, the surface 11a of the substrate 11 is more easily formed in the composite sheet 1 for forming a protective film. It is preferably a smooth surface.

The composite sheet 1 for forming a protective film shown in Fig. 1 is attached to the surface 13a of the film 13 for protective film formation in a state where the release film 15 is removed. The back surface of the bulk wafer (not shown) is used by attaching the exposed surface of the uncovered protective film forming film 13 on the surface 12a of the adhesive layer 12 to a jig such as a ring frame.

Fig. 2 is a cross-sectional view schematically showing another embodiment of a composite sheet for forming a protective film according to an aspect of the present invention. In addition, in FIG. 2, the same components as those in FIG. 1 are denoted by the same reference numerals, and the detailed description thereof will be omitted. This case is also the same for the graphs of Fig. 2 and later.

The composite film 2 for forming a protective film shown here is a film for forming a protective film for the entire area of the surface 12a of the adhesive layer 12, and an adhesive for the part of the surface 23a of the film 23 for forming a protective film is laminated. The layer 16 is provided with a release film 15 on the exposed surface of the adhesive layer 16 for the deposition of the protective film forming film 23 and the surface 16a (upper surface and side surface) of the adhesive layer 16 for the jig. Other than this, it is the same as the composite sheet 1 for protective film formation shown in FIG.

Further, a void portion may be present between the surface 23a of the release film 15 and the film 23 for forming a protective film or the surface 16a of the adhesive layer 16 for a fixture. For example, the side portion of the adhesive agent layer 16 or the vicinity of the adhesive agent layer 16 in the surface 23a of the protective film forming film 23 is likely to generate the void portion.

In the composite sheet 2 for forming a protective film, similarly to the case of the composite sheet 1 for forming a protective film, the surface of the coating layer 14 opposite to the surface (surface) 14a of the supporting sheet 10 (substrate 11) is opposite. The haze measured in the direction of the surface (back surface) 14b was 47% or less. Therefore, the protective film formed of the film 23 for forming a protective film can be clearly subjected to laser printing.

Further, when the composite sheet 2 for forming a protective film is provided with the coating layer 14, even when it is wound up to form a roll, adhesion is suppressed.

The composite film 2 for forming a protective film shown in FIG. 2 is attached to the back surface of a semiconductor wafer (not shown) on the surface 23a of the film 23 for protective film formation in a state in which the release film 15 is removed, and the jig is attached. The upper surface of the surface 16a of the adhesive layer 16 is attached to a jig such as a ring frame and used.

The composite sheet for forming a protective film of the present invention is not limited to those shown in FIGS. 1 to 2, and a part of the components shown in FIGS. 1 to 2 may be changed or deleted within the range in which the function of the present invention is not impaired. It may be formed by adding another structure to the person described so far.

Hereinafter, each configuration of the composite sheet for forming a protective film according to an embodiment of the present invention will be described in more detail.

○Support piece

The support sheet is not particularly limited as long as it can provide the film for forming a protective film, and for example, it can be used to prevent formation of a protective film. A release sheet that adheres to dust or the like on the surface of the film, and a role of a dicing sheet or the like for protecting the surface of the film for forming a protective film in a dicing step or the like.

Preferred examples of the support sheet include those formed by a substrate which is generally used in the field of processing sheets for semiconductor wafers, and those in which a substrate and an adhesive are laminated.

The support sheet may be composed of one layer (single layer) or a plurality of layers of two or more layers. In the case where the support sheet is composed of a plurality of layers, the plurality of layers may be the same or different from each other. That is, all layers may be the same, or all layers may be different, or only a part of the layers may be the same. Further, in the case where the plural layers are different from each other, the combination of these plural layers is not particularly limited. Here, the fact that the plural layers are different from each other means that at least one of the materials and thicknesses of the respective layers are different from each other.

The thickness of the support sheet can be appropriately selected according to the purpose, and it is preferable to provide sufficient flexibility to the composite sheet for forming a protective film and to improve the adhesion to the semiconductor wafer, preferably 10 μm. It is up to 500 μm, more preferably from 20 μm to 350 μm, still more preferably from 30 μm to 200 μm.

Here, the "thickness of the support sheet" means the total thickness of each layer constituting the support sheet, for example, in the case of a support sheet in which a base material and an adhesive layer are laminated, it means the thickness of the base material and the adhesive layer. The total value of the thickness.

Further, at least one surface of the support sheet may be an uneven surface, and the thickness of the support sheet may be calculated as a starting point of the tip end of the convex portion of the uneven surface of the support sheet including the convex portion.

‧Substrate

The material of the substrate is preferably a variety of resins, and specific examples thereof include polyethylene (LDPE; Low Density Polyethylene, Linear Low Density Polyethylene, LLDPE; Density polyethylene (HDPE; High Density Polyethylene), polypropylene, ethylene-propylene copolymer, polybutene, polybutadiene, polymethylpentene, polyvinyl chloride, vinyl chloride copolymer, polyparaphenylene Ethylene formate, polyethylene naphthalate, polybutylene terephthalate, polyurethane, polyacrylamide, polyimide, ethylene-vinyl acetate copolymer, Ionic polymer resin, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylate copolymer, polystyrene, polycarbonate, fluororesin, cyanide, modified product, or any of these resins Linkage or copolymer, etc.

In addition, in this specification, "(meth)acrylic" is a concept including both "acrylic" and "methacrylic".

In the case where the support sheet is formed by laminating other layers such as a substrate and an adhesive layer, the thickness of the substrate may be appropriately selected depending on the purpose, and is preferably 15 μm to 300 μm, more preferably 20 μm to 200 μm. By making the substrate The thickness is such a range, and the flexibility of the composite sheet for forming a protective film and the adhesion to a semiconductor wafer or a semiconductor wafer are further improved.

The substrate may be composed of one layer (single layer) or a plurality of layers of two or more layers. In the case where the substrate is composed of a plurality of layers, the plurality of layers may be the same or different from each other. Here, the phrase "the plurality of layers may be the same or different from each other" means the same as the case of the aforementioned support sheet.

In the case where the substrate is composed of a plurality of layers, the total thickness of each layer is preferably set so as to be a preferred substrate thickness as described above.

The surface roughness Ra of the surface (surface) of the substrate having the adhesive layer is preferably from 0.001 μm to 0.1 μm, more preferably from 0.005 μm to 0.08 μm, still more preferably from 0.01 μm to 0.04 μm. By setting the surface roughness Ra of the surface of the substrate to be equal to or less than the above upper limit value, it is possible to perform laser printing more clearly on the protective film.

The surface roughness Ra of the surface of the substrate can be adjusted, for example, by molding conditions of the substrate, surface treatment conditions, and the like.

Further, as a method of separating a semiconductor wafer into a semiconductor wafer by dicing, for example, laser cutting by cutting a semiconductor wafer using a blade, laser cutting by laser irradiation, or laser cutting into a semiconductor wafer, or A method of cutting water or the like into a semiconductor wafer by spraying water containing an abrasive.

On the other hand, as a method of separating a semiconductor wafer into a semiconductor wafer, in addition to the method of using these dicing, it is also possible to irradiate the laser light in the infrared region so as to focus on a focus set inside the semiconductor wafer. After the modified layer is formed inside the semiconductor wafer, a force is applied to the semiconductor wafer, and the semiconductor wafer is divided and separated by the formation portion of the modified layer.

When the surface roughness Ra of the surface of the substrate is, for example, 0.01 μm to 0.2 μm, the composite sheet for forming a protective film having such a substrate is suitable for forming a modified layer inside the semiconductor wafer to form a semiconductor wafer. Used when separating.

On the other hand, the surface roughness Ra of the surface (back surface) on the side opposite to the surface (surface) on which the adhesive layer is provided in the substrate, in other words, the surface (surface) of the support sheet which is provided with the film for forming a protective film The surface roughness Ra of the side surface (back surface) is preferably 0.001 μm to 4 μm, more preferably 0.005 μm to 3.7 μm, still more preferably 0.01 μm to 3.4 μm, still more preferably 0.02 μm to 3.1 μm. By setting the surface roughness Ra of the back surface of the substrate to be equal to or less than the above upper limit value, the surface roughness Ra of the surface on the side opposite to the side contacting the support sheet in the coating layer can be more easily reduced, and becomes more It is easy to perform laser printing on the protective film clearly.

The surface roughness Ra of the back surface of the substrate can be adjusted, for example, by molding conditions of the substrate, surface treatment conditions, and the like.

The resin used as the material of the substrate may also be a crosslinked person.

Further, the resin which is a material of the base material may be formed by extrusion of a thermoplastic resin, or may be formed by stretching, or may be formed by a known means by a curable resin. Layered and cured to form a film.

In addition, the substrate may be a colorant or a printer.

The substrate is preferably a polypropylene-containing material because it is excellent in heat resistance and has an adaptability by moderate flexibility and a good pick-up property.

The substrate containing polypropylene may be, for example, a single layer or a plurality of layers composed of only polypropylene, or a substrate in which a plurality of layers of a polypropylene layer and a resin other than polypropylene are laminated.

When the film for forming a protective film is thermosetting, by making the substrate heat-resistant, deterioration of the substrate due to heat can be suppressed, and occurrence of defects in the manufacturing process of the semiconductor device can be effectively suppressed.

The substrate may be embossed by a sand blasting treatment, a solvent treatment or the like in order to improve the adhesion to the adhesive layer or the film for forming a protective film provided on the substrate; or to perform corona treatment Oxidation treatment, electron beam irradiation treatment, plasma treatment, ozone-ultraviolet irradiation treatment, flame treatment, chromic acid treatment, hot air treatment, etc. Alternatively, the substrate can be a surface treated substrate.

‧Adhesive layer

A well-known one can use suitably the said adhesive layer.

The adhesive layer can be formed using an adhesive composition containing various components such as an adhesive for constituting the adhesive layer. The ratio of the components in the adhesive composition which are not vaporized at normal temperature to each other is usually the same as the ratio of the contents of the aforementioned components of the adhesive layer to each other. In addition, in the present specification, the term "normal temperature" means a temperature which is not particularly cold or hot, that is, a normal temperature, and examples thereof include a temperature of 15 ° C to 25 ° C.

The thickness of the adhesive layer can be appropriately selected depending on the purpose, and is preferably from 1 μm to 100 μm, more preferably from 2 μm to 80 μm, still more preferably from 3 μm to 50 μm.

The adhesive layer may be composed of one layer (single layer) or a plurality of layers of two or more layers. In the case where the adhesive layer is composed of a plurality of layers, the plurality of layers may be the same or different from each other. Here, the phrase "the plurality of layers may be the same or different from each other" means the same as the case of the aforementioned support sheet.

In the case where the adhesive layer is composed of a plurality of layers, the total thickness of each layer is preferably set so as to be the thickness of the above-mentioned preferred adhesive layer.

Examples of the adhesive include an adhesive resin such as an acrylic resin, an urethane resin, a rubber resin, a polyoxyn resin, or a vinyl ether resin, and the function of the resin is focused on. For example, an energy ray-curable resin or the like can be mentioned.

In the present specification, the term "energy line" means an energy source having electromagnetic waves or charged particle lines, and examples thereof include ultraviolet rays, electron beams, and the like. For example, a high-pressure mercury lamp, a fusion H lamp, a xenon lamp, or the like can be used as the ultraviolet light source. The electron beam can illuminate a beam generated by an electron beam accelerator or the like.

Examples of the energy ray-curable resin include those having a polymerizable group such as a (meth)acryl fluorenyl group or a vinyl group.

The adhesive resin is preferably an acrylic resin, and more preferably a (meth) acrylate copolymer containing a constituent unit derived from (meth) acrylate.

When the pressure-sensitive adhesive layer contains a component which is polymerized by irradiation of an energy ray, such as an energy ray-curable resin, it becomes an energy ray-curable adhesive layer, and the energy is removed by irradiation of an energy ray to lower the adhesion. The picking up of the semiconductor wafer with the protective film described above becomes easy. Such an adhesive layer can be formed, for example, by using various adhesive compositions containing a component polymerized by irradiation with an energy ray.

<<Adhesive composition>>

The binder composition is preferably a component which is polymerized by irradiation with an energy ray. Examples of such an adhesive composition include those containing an acrylic resin and an energy ray polymerizable compound. Hereinafter, it may be simply referred to as "adhesive composition (i)"); the above-mentioned acrylic resin having a hydroxyl group and having a polymerizable group in a side chain (for example, having a hydroxyl group) The group having a polymerizable group via a urethane bond in the side chain and the isocyanate-based crosslinking agent (hereinafter sometimes referred to simply as "adhesive composition (ii)").

<Adhesive Composition (i)>

The adhesive composition (i) contains the above-mentioned acrylic resin and an energy ray polymerizable compound as essential components.

Hereinafter, each component will be described.

[Acrylic resin]

Preferred examples of the acrylic resin in the adhesive composition (i) include a monomer other than a (meth) acrylate and, if necessary, a (meth) acrylate. A (meth) acrylate copolymer obtained by carrying out polymerization.

Examples of the (meth) acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, and (meth)acrylic acid. Amyl ester, hexyl (meth) acrylate, heptyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ( N-decyl methacrylate, isodecyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth) acrylate, lauryl (meth) acrylate ((methyl) ) lauryl acrylate), tridecyl (meth) acrylate, tetradecyl (meth) acrylate (myristyl (meth) acrylate), pentadecyl (meth) acrylate, (a) Propylene Cetyl acid ester (palmityl (meth) acrylate), heptadecyl (meth) acrylate, octadecyl (meth) acrylate (stearyl (meth) acrylate), (A) a (meth)acrylic acid alkyl ester having an alkyl group of an alkyl ester such as a chain structure of a carbon number of 1 to 18; a (meth)acrylic acid cycloalkyl ester such as isobornyl acrylate, dicyclopentyl (meth) acrylate; arylalkyl (meth) acrylate such as benzyl (meth) acrylate; (methyl) (cyclo)alkyl (meth) acrylate such as dicyclopentenyl acrylate; cycloalkenyloxyalkyl (meth) acrylate such as dicyclopentenyloxyethyl (meth)acrylate; (meth) propylene a glycidyl group-containing (meth) acrylate such as glycidyl (meth)acrylate; hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, (meth) acrylate 2-hydroxypropyl ester, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc. A hydroxyl group-containing (meth) acrylate or the like.

Examples of the monomer other than the (meth) acrylate include (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N-methylol acrylamide.

The various monomers such as the (meth) acrylate constituting the acrylic resin and the monomer other than the (meth) acrylate may be used alone or in combination of two or more.

The acrylic resin contained in the adhesive composition (i) may be used alone or in combination of two or more.

The content of the acrylic resin of the adhesive composition (i) is preferably 40% by mass to 99% by mass, more preferably 50% by mass based on the total amount of all the components other than the solvent in the adhesive composition (i). % to 91% by volume.

[Energy ray polymerizable compound]

The energy ray-polymerizable compound is a compound which is polymerized by irradiation with an energy ray, and examples thereof include an energy ray polymerizable group having an energy ray-curable double bond in the molecule.

Examples of the energy ray polymerizable compound include low molecular weight compounds (monofunctional or polyfunctional monomers and oligomers) having an energy ray polymerizable group, and more specifically, trimethylolpropane III Acrylate, tetramethylolmethane tetraacrylate, pentaerythritol triacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol Acrylate such as acrylate; acrylate containing cyclic aliphatic skeleton such as dicyclopentadiene dimethoxy diacrylate; polyethylene glycol diacrylate, oligoester acrylate, urethane acrylate An acrylate-based compound such as a polymer, an epoxy-modified acrylate, a polyether acrylate or an itaconic acid oligomer.

The molecular weight of the above energy ray polymerizable compound is preferably from 100 to 30,000, more preferably from 300 to 10,000.

The energy ray polymerizable compound contained in the adhesive composition (i) may be used alone or in combination of two or more.

The content of the energy ray polymerizable compound of the adhesive composition (i) is preferably from 1 part by mass to 125 parts by mass, more preferably from 10 parts by mass to 125 parts by mass, per 100 parts by mass of the content of the acrylic resin.

[Photopolymerization initiator]

The adhesive composition (i) may contain a photopolymerization initiator in addition to the acrylic resin and the energy ray polymerizable compound.

The photopolymerization initiator is preferably a known one, and specific examples thereof include 4-(2-hydroxyethoxy)phenyl (2-hydroxy-2-propyl) ketone and α-hydroxy-α, α. '-Dimethylacetophenone, 2-methyl-2-hydroxypropiophenone, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl) -α-keto alcohol compound such as -propenyl)-benzyl]phenyl}-2-methyl-propan-1-one; methoxyacetophenone, 2,2-dimethoxy-2-benzene Benzophenone, 2,2-diethoxyacetophenone, 2-methyl-1-[4-(methylthio)phenyl]-2-N-morpholinylpropan-1-one and the like An ketone-based compound; a benzoin ether compound such as benzoin ethyl ether, benzoin isopropyl ether, fennel aceton methyl ether; a ketal compound such as benzoin dimethyl ketal; an aromatic sulfonium such as 2-naphthalene sulfonium chloride a chlorine-based compound; a photoactive lanthanide compound such as 1-benzophenone-1,1-propanedione-2-(O-ethoxycarbonyl)anthracene; benzophenone; Benzophenone benzoic acid, benzophenone compound such as 3,3'-dimethyl-4-methoxybenzophenone; Thioxanthone (9H-thioxanthen-9-one), 2- Chloro-thioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropyl-thioxanthone, 2,4-dichloro-thioxanthone, 2,4-diethyl a thioxanthone compound such as a thioxanthone or a 2,4-diisopropyl-thioxanthone; a camphorquinone; a halogenated ketone; a mercaptophosphine oxide; a decylphosphonate.

The photopolymerization initiator contained in the adhesive composition (i) may be used alone or in combination of two or more.

In the case of using a photopolymerization initiator, the content of the photopolymerization initiator of the adhesive composition (i) is preferably from 0.1 part by mass to 10 parts by mass based on 100 parts by mass of the energy-polymerizable compound. More preferably, it is 1 part by mass to 5 parts by mass. By setting the content of the photopolymerization initiator to the above lower limit value, the effect by using a photopolymerization initiator can be sufficiently obtained. In addition, when the content of the photopolymerization initiator is less than or equal to the above upper limit, the occurrence of by-products from an excessive amount of the photopolymerization initiator is suppressed, and the curing of the pressure-sensitive adhesive layer proceeds more satisfactorily.

[crosslinking agent]

The adhesive composition (i) may contain a crosslinking agent in addition to the acrylic resin and the energy ray polymerizable compound.

Examples of the crosslinking agent include an organic polyvalent isocyanate compound and an organic polyvalent quinone imide compound.

Examples of the organic polyvalent isocyanate compound include an aromatic polyisocyanate compound, an aliphatic polyisocyanate compound, an alicyclic polyisocyanate compound, and terpolymers, isomeric cyanurates, and adducts of these compounds; A terminal isocyanate urethane prepolymer obtained by reacting the aromatic polyvalent isocyanate compound, the aliphatic polyvalent isocyanate compound or the alicyclic polyvalent isocyanate compound with a polyol compound. The above-mentioned adduct refers to the above-mentioned aromatic polyisocyanate compound, aliphatic polyisocyanate compound or alicyclic polyisocyanate compound, and low molecular weight such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane or castor oil. A reactant of a compound of active hydrogen.

As the above-mentioned organic polyvalent isocyanate compound, more specifically, for example, 2,4-toluene diisocyanate; 2,6-toluene diisocyanate; 1,3-benzenedimethyl diisocyanate; 1,4-dimethylbenzene Isocyanate; diphenylmethane-4,4'-diisocyanate; diphenylmethane-2,4'-diisocyanate; 3-methyldiphenylmethane diisocyanate; 1,6-hexamethylene diisocyanate; isophorone Diisocyanate; dicyclohexylmethane-4,4'-diisocyanate; dicyclohexylmethane-2,4'-diisocyanate; addition of toluene diisocyanate to all or a part of hydroxyl groups of a polyol such as trimethylolpropane and a compound obtained by either or both of 6-hexamethylene diisocyanate; an isocyanate diisocyanate or the like.

Examples of the organic polyvalent quinone imine compound include N,N'-diphenylmethane-4,4'-bis(1-aziridine carboxamide), and trimethylolpropane tris(β-nitrogen). Propionyl propionate), tetramethylol methane tris(β-aziridine propionate), N,N'-toluene-2,4-bis(1-aziridine carboxamide) Ethyl melamine and the like.

When an isocyanate compound is used as a crosslinking agent, it is preferable to use a hydroxyl group-containing polymer as the acrylic resin. When the crosslinking agent has an isocyanate group and the acrylic resin has a hydroxyl group, the adhesive layer can be easily introduced into the crosslinked structure by the reaction of these isocyanate groups with a hydroxyl group.

The crosslinking agent contained in the adhesive composition (i) may be used alone or in combination of two or more.

In the case of using a crosslinking agent, the content of the crosslinking agent of the adhesive composition (i) is preferably 0.01 parts by mass to 20 parts by mass, more preferably 0.1% by mass based on 100 parts by mass of the acrylic resin. Parts to 16 parts by mass.

[solvent]

It is preferable that the adhesive composition (i) further contains a solvent in addition to the acrylic resin and the energy ray polymerizable compound.

The solvent is not particularly limited, and examples thereof include hydrocarbons such as toluene and xylene; methanol, ethanol, 2-propanol, and isobutanol (2-methyl group). Alcohols such as propan-1-ol) and 1-butanol; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; dimethylformamide and N-methylpyrrolidone; An amine (a compound having a guanamine bond) or the like.

The solvent contained in the adhesive composition (i) may be one type or two or more types.

The content of the solvent in the case where the adhesive composition (i) contains a solvent is preferably from 40% by mass to 90% by mass, more preferably from 50% by mass to 80% by mass.

[Other ingredients]

The adhesive composition (i) may contain, in addition to the acrylic resin and the energy ray-polymerizable compound, other components which are not the aforementioned photopolymerization initiator, crosslinking agent and solvent, within the range which does not impair the efficacy of the present invention. .

The above-mentioned other components are preferably known, and can be arbitrarily selected according to the purpose, and are not particularly limited. Preferred examples thereof include a dye, a pigment, a deterioration preventive agent, an antistatic agent, a flame retardant, and a polyoxonium compound. , various additives such as chain transfer agents.

The other components contained in the adhesive composition (i) may be one type or two or more types.

<Adhesive Composition (ii)>

The adhesive composition (ii) contains an acrylic resin having a hydroxyl group and having a polymerizable group in a side chain (for example, having a hydroxyl group and having an amine group on the side chain) An acid ester group is used as the acid ester group, and an isocyanate type crosslinking agent is an essential component.

In the case of using the adhesive composition (ii), by using the acrylic resin to have a polymerizable group on the side chain, the energy ray polymerizable compound is used as in the case of the adhesive composition (i) and by irradiation. The peeling property from the adherend is further improved by the decrease in the adhesiveness of the adhesive layer after the polymerization reaction (curing), and the pick-up property of the semiconductor wafer with the protective film is further improved as compared with the case where the energy ray is subjected to the polymerization reaction. .

In addition, in the present specification, the description of the "acrylic resin" in the adhesive composition (ii) means "acrylic resin having a polymerizable group in a side chain" unless otherwise specified.

[Acrylic resin]

Examples of the acrylic resin having a polymerizable group in the side chain include a hydroxyl group-free (meth) acrylate having no hydroxyl group as a monomer, and a hydroxyl group-containing (meth) acrylate having a hydroxyl group. When a hydroxyl group-containing compound is copolymerized, an isocyanate group of a compound having an isocyanate group and a polymerizable group is reacted with a hydroxyl group of the obtained hydroxyl group-containing copolymer to form a urethane bond.

Examples of the hydroxyl group-free (meth) acrylate include those other than the hydroxyl group-containing (meth) acrylate in the (meth) acrylate in the adhesive composition (i).

Further, examples of the hydroxyl group-containing compound include the same as the hydroxyl group-containing (meth) acrylate in the adhesive composition (i).

The hydroxy (meth) acrylate and the hydroxyl group-containing compound constituting the acrylic resin may be used alone or in combination of two or more.

Examples of the compound having an isocyanate group and a polymerizable group include an isocyanate group-containing (meth) acrylate such as 2-methylpropenyloxyethyl isocyanate.

The compound having an isocyanate group and a polymerizable group in the acrylic resin may be one type or two or more types.

The acrylic resin contained in the adhesive composition (ii) may be used alone or in combination of two or more.

The content of the acrylic resin of the adhesive composition (ii) is preferably from 80% by mass to 99% by mass, more preferably 90% by mass based on the total of all the components other than the solvent in the adhesive composition (ii). % to 97% by mass.

[Isocyanate crosslinking agent]

The isocyanate-based crosslinking agent is, for example, the same as the above-mentioned organic polyvalent isocyanate compound as a crosslinking agent in the adhesive composition (i).

The isocyanate crosslinking agent contained in the adhesive composition (ii) may be one type or two or more types.

The number of moles of the isocyanate group of the isocyanate-based crosslinking agent in the adhesive composition (ii) is preferably 0.2 with respect to the number of moles of the hydroxyl group of the acrylic resin in the adhesive composition (ii). Up to 3 times. When the number of moles of the isocyanate group is at least the above lower limit value, the peeling property from the adherend due to the decrease in the adhesiveness of the adhesive layer after curing is improved, and the pick-up property of the semiconductor wafer with the protective film is improved. Upgrade. In addition, when the number of moles of the isocyanate group is at most the above upper limit value, generation of by-products due to reaction between the isocyanate-based crosslinking agents can be further suppressed.

The content of the isocyanate-based crosslinking agent of the adhesive composition (ii) may be appropriately adjusted so that the number of moles of the isocyanate group becomes as described above, and based on the satisfaction of the above conditions, the acrylic resin is used. The content is 100 parts by mass, preferably 0.01 parts by mass to 20 parts by mass, more preferably 0.1 parts by mass to 15 parts by mass, still more preferably 0.3 parts by mass to 12 parts by mass.

[Photopolymerization initiator]

The adhesive composition (ii) may contain a photopolymerization initiator in addition to the acrylic resin and the isocyanate crosslinking agent.

The photopolymerization initiator is, for example, the same as in the case of the adhesive composition (i).

The photopolymerization initiator contained in the adhesive composition (ii) may be used alone or in combination of two or more.

In the case of using a photopolymerization initiator, the content of the photopolymerization initiator of the adhesive composition (ii) is preferably from 0.05 part by mass to 20 parts by mass per 100 parts by mass of the acrylic resin.

When the content of the photopolymerization initiator is at least the above lower limit value, the effect by using a photopolymerization initiator can be sufficiently obtained. In addition, when the content of the photopolymerization initiator is less than or equal to the above upper limit, generation of by-products from an excessive amount of the photopolymerization initiator is suppressed, and curing of the adhesive layer proceeds more satisfactorily.

[solvent]

It is preferable that the adhesive composition (ii) further contains a solvent in addition to the acrylic resin and the isocyanate crosslinking agent.

The solvent is, for example, the same as in the case of the adhesive composition (i).

The solvent contained in the adhesive composition (ii) may be one type or two or more types.

The content of the solvent in the case where the adhesive composition (ii) contains a solvent is preferably from 40% by mass to 90% by mass, more preferably from 50% by mass to 80% by mass.

[Other ingredients]

The adhesive composition (ii) may contain, in addition to the acrylic resin and the isocyanate crosslinking agent, other components which are not the aforementioned photopolymerization initiator and solvent, within the range which does not impair the effects of the present invention.

Examples of the other components include the same as those in the case of the adhesive composition (i).

The other components contained in the adhesive composition (ii) may be one type or two or more types.

As described above, the adhesive composition containing the component polymerized by irradiation with the energy ray has been described. However, the adhesive layer may be formed by using an adhesive composition which does not contain a component which is polymerized by irradiation with an energy ray. That is, the adhesive layer may be a non-energy line curable adhesive layer which does not have energy ray curability.

Preferred examples of the non-energy-curable adhesive composition include those containing an acrylic resin and a crosslinking agent (hereinafter, simply referred to as "adhesive composition (iii)"). Any component containing a solvent and other components not belonging to the solvent.

<Adhesive Composition (iii)>

The acrylic resin, the crosslinking agent, the solvent, and other components contained in the adhesive composition (iii) are the same as those of the adhesive composition (i).

The content of the acrylic resin of the adhesive composition (iii) is preferably 40% by mass to 99% by mass, and more preferably 50% by mass based on the total amount of all the components other than the solvent in the adhesive composition (iii). % to 93% by mass.

The content of the crosslinking agent of the adhesive composition (iii) is preferably from 3 parts by mass to 30 parts by mass, more preferably from 5 parts by mass to 25 parts by mass, per 100 parts by mass of the acrylic resin.

The adhesive composition (iii) is the same as the adhesive composition (i) except for the foregoing aspects.

<<Manufacturing method of adhesive composition>>

The above-mentioned adhesive composition such as the adhesive composition (i) to (iii) is obtained by blending the above-mentioned adhesive, components other than the above-mentioned adhesive as needed, and the like to form components of the respective adhesive compositions. .

The order of addition of each component is not particularly limited, and two or more components may be simultaneously added.

The method of mixing the components at the time of preparation is not particularly limited, and is appropriately selected from known methods such as a method of mixing by stirring a stirring blade or a stirring blade, a method of mixing by using a mixer, and a method of applying ultrasonic waves for mixing. Just fine.

The temperature and time of each component to be added and mixed are not particularly limited as long as the respective components do not deteriorate, and the temperature may be appropriately adjusted, and the temperature is preferably from 15 ° C to 30 ° C.

○ film for protective film formation

The film for forming a protective film may be either thermosetting or energy ray curable. The film for forming a protective film is cured to finally become a protective film having high impact resistance. This protective film prevents, for example, the occurrence of cracking of the semiconductor wafer after the dicing step.

For the film for forming a protective film, the composition for forming a thermosetting protective film or the composition for forming an energy ray-curable protective film (hereinafter referred to as "the composition for forming a protective film" may be used. ) formed.

The film for forming a protective film may be only one layer (single layer) or a plurality of layers of two or more layers; in the case of a plurality of layers, the plurality of layers may be the same or different, and the combination of the plurality of layers is not Specially limited.

The thickness of the film for forming a protective film is not particularly limited, but is preferably from 1 μm to 100 μm, more preferably from 5 μm to 75 μm, still more preferably from 5 μm to 50 μm. When the thickness of the film for forming a protective film is at least the above lower limit value, the adhesion force to the semiconductor wafer and the semiconductor wafer as the adherend becomes larger. In addition, when the thickness of the film for forming a protective film is equal to or less than the above upper limit value, when the semiconductor wafer is picked up, the protective film as a cured product can be more easily cut by the shearing force.

‧The film for forming a thermosetting protective film

The film for forming a thermosetting protective film is preferably, for example, a polymer component (A) and a thermosetting component (B). The polymer component (A) is a component which is formed by a polymerization reaction of a polymerizable compound. Further, the thermosetting component (B) is a component which can be subjected to a curing (polymerization) reaction by using heat as a reaction initiation condition. Further, in the present invention, the polymerization reaction also includes a polycondensation reaction.

<<Composition for forming a thermosetting protective film>>

The film for forming a thermosetting protective film can be formed using a composition for forming a thermosetting protective film containing the constituent material. For example, a composition for forming a thermosetting protective film can be applied to a surface to be formed of a film for forming a thermosetting protective film, and if necessary, it can be dried to form a film for forming a thermosetting protective film on a target portion. The ratio of the content of the components which are not vaporized at normal temperature in the thermosetting protective film-forming composition is usually the same as the ratio of the components of the thermosetting protective film-forming film. Here, the "normal temperature" is as described above.

The application of the composition for forming a thermosetting protective film may be carried out by a known method, and examples thereof include an air knife coater, a knife coater, a bar coater, a gravure coater, and a roll coating. Machine, roll coater, curtain coater, die coater, knife coater, screen coater, meyer bar coater, staple coater, etc. The method of the coater.

The drying conditions of the composition for forming a thermosetting protective film are not particularly limited, and when the composition for forming a thermosetting protective film contains a solvent, it is preferably dried by heating; in this case, for example, It is preferably dried at 70 ° C to 130 ° C for 10 seconds to 5 minutes.

<Protective film forming composition (III-1)>

The composition for forming a thermosetting protective film, for example, a thermosetting protective film forming composition (III-1) containing the polymer component (A) and the thermosetting component (B) (in the present specification) It may be simply referred to as "protective film-forming composition (III-1)").

[Polymer component (A)]

The polymer component (A) is a polymer compound for imparting film-forming property or flexibility to the film for forming a thermosetting protective film.

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

Examples of the polymer component (A) include an acrylic resin (a resin having a (meth)acrylonitrile group), a polyester, and a urethane resin (a resin having a urethane bond). Acrylic urethane resin, polyoxynene resin (resin having a siloxane coupling), rubber resin (with a rubber knot) The resin of the structure, the phenoxy resin, the thermosetting polyimide, and the like are preferably an acrylic resin.

A well-known acrylic polymer is mentioned as said acrylic resin in the polymer component (A).

The weight average molecular weight (Mw) of the acrylic resin is preferably from 10,000 to 2,000,000, more preferably from 100,000 to 1,500,000. When the weight average molecular weight of the acrylic resin is at least the above lower limit value, the shape stability of the film for forming a thermosetting protective film (the stability over time during storage) is improved. In addition, when the weight average molecular weight of the acrylic resin is equal to or less than the above-described upper limit, the film for forming a thermosetting protective film can easily follow the uneven surface of the adherend, and further suppress the adherend and the thermosetting property. A case where pores or the like are formed between the films for film formation.

The glass transition temperature (Tg) of the acrylic resin is preferably from -60 ° C to 70 ° C, more preferably from -30 ° C to 50 ° C. When the Tg of the acrylic resin is at least the above lower limit value, the adhesion between the protective film and the support sheet is suppressed, and the peeling property of the support sheet is improved. In addition, when the Tg of the acrylic resin is equal to or less than the above-described upper limit, the adhesion between the film for forming a thermosetting protective film and the protective film and the adherend is improved.

Examples of the acrylic resin include a polymer of one or two or more kinds of (meth) acrylates, and a (meth)acrylic acid and itaconic acid. A copolymer of two or more kinds of monomers such as vinyl acetate, acrylonitrile, styrene, and N-methylol acrylamide.

Examples of the (meth) acrylate constituting the acrylic resin include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, and isopropyl (meth) acrylate. Ester, n-butyl (meth)acrylate, isobutyl (meth)acrylate, second butyl (meth)acrylate, tert-butyl (meth)acrylate, amyl (meth)acrylate, (A) Ethyl acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, (meth)acrylic acid Anthracene ester, isodecyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauryl (meth)acrylate) , tridecyl (meth)acrylate, tetradecyl (meth)acrylate (myristyl (meth)acrylate), pentadecyl (meth)acrylate, (meth)acrylic acid An alkyl ester (palmityl (meth) acrylate), heptadecyl (meth) acrylate, octadecyl (meth) acrylate (stearyl (meth) acrylate), etc. The alkyl group has a carbon number of 1 to 18 Chain-structured alkyl (meth)acrylate; isobornyl (meth)acrylate, cycloalkyl (meth)acrylate such as dicyclopentyl (meth)acrylate; benzyl (meth)acrylate An arylalkyl (meth)acrylate; a cycloalkylenyl (meth)acrylate such as dicyclopentenyl (meth)acrylate; a dicyclopentenyloxyethyl (meth)acrylate; a cycloalkyloxyalkyl acrylate; (meth) acrylimide; a glycidyl group-containing (meth) acrylate such as glycidyl (meth) acrylate; hydroxymethyl (meth) acrylate; 2-hydroxyethyl methacrylate, (meth) propylene 2-hydroxypropyl acid ester, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate A hydroxyl group-containing (meth) acrylate, a substituted amino group-containing (meth) acrylate such as N-methylaminoethyl (meth) acrylate, or the like. Here, the "substituted amino group" means a group in which one or two hydrogen atoms of an amine group are substituted with a group other than a hydrogen atom.

The acrylic resin may be, for example, selected from the group consisting of (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N-methylol acrylamide. One or two or more kinds of monomers are copolymerized.

The monomer constituting the acrylic resin may be one type or two or more types. When two or more types are used, the combination and ratio of these may be arbitrarily selected.

The acrylic resin may have a functional group capable of bonding with another compound such as a vinyl group, a (meth) acrylonitrile group, an amine group, a hydroxyl group, a carboxyl group or an isocyanate group. The functional group of the acrylic resin may be bonded to another compound via the crosslinking agent (F) described below, or may be directly bonded to another compound without passing through the crosslinking agent (F). When the acrylic resin is bonded to another compound by the above 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 embodiment, a thermoplastic resin (hereinafter, simply referred to as "thermoplastic resin") other than the acrylic resin may be used in combination with the acrylic resin as the polymer component (A).

By using the thermoplastic resin, the peeling property of the protective film from the support sheet is improved, or the film for forming a thermosetting protective film is likely to follow the uneven surface of the adherend, and is more inhibited from being adhered to the adherend. A case where pores or the like are formed between the films for forming a thermosetting protective film.

The weight average molecular weight of the aforementioned thermoplastic resin is preferably from 1,000 to 100,000, more preferably from 3,000 to 80,000.

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

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

The thermoplastic resin contained in the protective film-forming composition (III-1) and the film for forming a thermosetting protective film may be one type or two or more types. When two or more types are used, these are Combinations and ratios can be arbitrarily selected.

In the protective film-forming composition (III-1), the ratio of the content of the polymer component (A) to the total content of all components other than the solvent (that is, heat) The content of the polymer component (A) of the film for forming a curable protective film is preferably from 5% by mass to 50% by mass, more preferably from 10% by mass to 40% by mass, regardless of the kind of the polymer component (A). More preferably, it is 15% by mass to 35% by mass.

The polymer component (A) is sometimes also a thermosetting component (B). In the case where the protective film-forming composition (III-1) contains a component belonging to both of the polymer component (A) and the thermosetting component (B), it is considered to be used for forming a protective film. The composition (III-1) contains a polymer component (A) and a thermosetting component (B).

[Thermal curable component (B)]

The thermosetting component (B) is a component for curing a film for forming a thermosetting protective film to form a hard protective film.

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

Examples of the thermosetting component (B) include an epoxy-based thermosetting resin, a thermosetting polyimide, a polyurethane, an unsaturated polyester, a polyoxyl resin, and the like. An epoxy-based thermosetting resin.

(epoxy thermosetting resin)

The epoxy-based thermosetting resin is composed of an epoxy resin (B1) and a heat curing agent (B2).

The epoxy-based thermosetting resin contained in the protective film-forming composition (III-1) and the film for forming a thermosetting protective film may be used alone or in combination of two or more kinds; in the case of two or more types The combinations and ratios of these can be arbitrarily selected.

‧Epoxy resin (B1)

Examples of the epoxy resin (B1) include a polyfunctional epoxy resin, a biphenyl compound, a bisphenol A diglycidyl ether and a hydrogenated product thereof, an o-cresol novolac epoxy resin, and the like. A cyclopentadiene type epoxy resin, a biphenyl type epoxy resin, a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a phenylene skeleton type epoxy resin, or the like, and a bifunctional or higher epoxy compound.

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

As the epoxy resin having an unsaturated hydrocarbon group, for example, a part of the epoxy group of the polyfunctional epoxy resin is converted into an unsaturated hydrocarbon. a compound formed from the base. Such a compound is obtained, for example, by addition of an epoxy group (meth)acrylic acid or a derivative thereof.

In addition, 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 has a polymerizable unsaturated group, and specific examples thereof include a vinyl group (ethenyl, vinyl), a 2-propenyl group (allyl), a (meth)acryl fluorenyl group, and a (meth) group. The acrylamide group or the like is preferably an acrylonitrile group.

In the present specification, the term "derivative" means that one or more hydrogen atoms of the original compound are substituted with a group other than a hydrogen atom (substituent).

The number average molecular weight of the epoxy resin (B1) is not particularly limited, and is preferably from 300 to 30,000 in terms of the curability of the film for forming a thermosetting protective film and the strength and heat resistance of the protective film after curing. More preferably, it is 300 to 10,000, and particularly preferably 300 to 3,000.

The epoxy group equivalent of the epoxy resin (B1) is preferably from 100 g/eq to 1100 g/eq, more preferably from 150 g/eq to 1000 g/eq.

One type of the epoxy resin (B1) may be used alone or two or more types may be used in combination. When two or more types are used in combination, the combinations and ratios thereof may be arbitrarily selected.

‧Hot curing agent (B2)

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

The thermosetting agent (B2) is, for example, a compound having two or more functional groups capable of reacting with an epoxy group in one molecule. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amine group, a carboxyl group, and an acid group-based group; and a phenolic hydroxyl group, an amine group, or an acid group is preferably acidified. More preferably, it is a phenolic hydroxyl group or an amine group.

In the thermosetting agent (B2), examples of the phenolic curing agent having a phenolic hydroxyl group include a polyfunctional phenol resin, a biphenol, a novolak type phenol resin, a dicyclopentadiene type phenol resin, and an aralkylphenol. Resin, etc.

In the thermosetting agent (B2), examples of the amine-based curing agent having an amine group include dicyandiamide (hereinafter sometimes abbreviated as "DICY").

The heat curing agent (B2) may also be one having an unsaturated hydrocarbon group.

Examples of the thermosetting agent (B2) having an unsaturated hydrocarbon group include a compound in which a part of a hydroxyl group of a phenol resin is substituted with a group having an unsaturated hydrocarbon group, and an unsaturated hydrocarbon group is directly bonded to an aromatic ring of the phenol resin. The compound formed by the base.

The aforementioned unsaturated hydrocarbon group in the heat curing agent (B2) is the same as the unsaturated hydrocarbon group in the above epoxy resin having an unsaturated hydrocarbon group.

In the case where a phenolic curing agent is used as the heat curing agent (B2), the heat curing agent (B2) preferably has a softening point or a high glass transition temperature in terms of improving the peeling property of the protective film from the support sheet. By.

The heat curing agent (B2) is preferably solid at normal temperature and does not exhibit curing activity for the epoxy resin (B1); on the other hand, it is melted by heating, and exhibits curing activity for the epoxy resin (B1). The heat curing agent (hereinafter sometimes referred to simply as "thermal active latent epoxy resin curing agent").

The thermally active latent epoxy resin curing agent is stably dispersed in the epoxy resin (B1) in a film for forming a thermosetting protective film at room temperature, and is compatible with the epoxy resin (B1) by heating. And reacted with epoxy resin (B1). By using the aforementioned thermally active latent epoxy resin curing agent, the storage stability of the composite sheet for forming a protective film is remarkably improved. For example, the movement of the film from the protective film forming film to the adjacent support sheets is suppressed, and the decrease in the thermosetting property of the film for forming a thermosetting protective film is effectively suppressed. In addition, since the degree of thermal curing of the film for forming a thermosetting protective film is further improved, the pick-up property of the semiconductor wafer with the following protective film is further improved.

Examples of the thermally active latent epoxy resin curing agent include an onium salt, a dibasic acid dioxime, a dicyandiamide, and an amine adduct of a curing agent.

In the thermosetting agent (B2), for example, a resin component such as a polyfunctional phenol resin, a novolac type phenol resin, a dicyclopentadiene phenol resin, or an aralkyl phenol resin The number average molecular weight is preferably from 300 to 30,000, more preferably from 400 to 10,000, still more preferably from 500 to 3,000.

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

The heat curing agent (B2) may be used singly or in combination of two or more kinds. When two or more types are used in combination, the combinations and ratios thereof may be arbitrarily selected.

In the film for forming a protective film (III-1) and the film for forming a thermosetting protective film, the content of the thermosetting agent (B2) is preferably 0.1 part by mass based on 100 parts by mass of the epoxy resin (B1). The portion is preferably 500 parts by mass, more preferably 1 part by mass to 200 parts by mass. When the content of the thermosetting agent (B2) is at least the above lower limit value, curing of the film for forming a thermosetting protective film becomes easier. In addition, when the content of the thermosetting agent (B2) is at most the above-described upper limit value, the moisture absorption rate of the film for forming a thermosetting protective film is lowered, and the reliability of the package obtained by using the composite sheet for forming a protective film is further improved. Upgrade.

In the film for protective film formation (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 heat curing agent (B2) With respect to 100 parts by mass of the polymer component (A), it is preferably 1 part by mass to 100 parts by mass, more preferably 1.5 parts by mass to 85 parts by mass, still more preferably 2 parts by mass to 70 parts by mass. By making thermosetting The aforementioned content of the chemical component (B) is in such a range, the adhesion between the protective film and the support sheet is suppressed, and the peeling property of the support sheet is improved.

[Curing accelerator (C)]

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

Preferred examples of the curing accelerator (C) include triethyldiamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol. Amine; 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4,5-di(hydroxymethyl)imidazole, 2-phenyl-4-methyl An imidazole such as a 5-hydroxymethylimidazole (an imidazole in which one or more hydrogen atoms are substituted with a hydrogen atom); an organic phosphine such as tributylphosphine, diphenylphosphine or triphenylphosphine (1) More than one hydrogen atom is substituted with an organic phosphine; tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium tetraphenylborate or the like.

The curing accelerator (C) contained in the protective film-forming composition (III-1) and the film for forming a thermosetting protective film may be used alone or in combination of two or more kinds; in the case of two or more types The combinations and ratios of these can be arbitrarily selected.

When the curing accelerator (C) is used, the curing accelerator (C) is used in the protective film forming composition (III-1) and the thermosetting protective film forming film. The content is preferably from 0.01 part by mass to 10 parts by mass, more preferably from 0.1 part by mass to 5 parts by mass, per 100 parts by mass of the content of the thermosetting component (B). When the content of the curing accelerator (C) is at least the above lower limit value, the effect by using the curing accelerator (C) is more remarkable. In addition, when the content of the curing accelerator (C) is equal to or less than the above-described upper limit, for example, the curing accelerator (C) having high polarity is prevented from moving in the film for forming a thermosetting protective film under high temperature and high humidity conditions. The efficiency of the segregation to the interface side of the adherend is improved, and the reliability of the package obtained by using the composite sheet for forming a protective film is further improved.

[Filling material (D)]

The protective film forming composition (III-1) and the thermosetting protective film forming film may further contain a filler (D). When the film for forming a thermosetting protective film contains the filler (D), the film obtained by curing the film for forming a thermosetting protective film is easily adjusted in thermal expansion coefficient, and the coefficient of thermal expansion is applied to the protective film. The object is formed and optimized, and the reliability of the package obtained by using the composite sheet for forming a protective film is further improved. In addition, when the film for forming a thermosetting protective film contains the filler (D), the moisture absorption rate of the protective film can be lowered or the heat dissipation property can be improved.

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

Examples of preferred inorganic fillers include cerium oxide, aluminum oxide, talc, calcium carbonate, titanium white, iron oxide, tantalum carbide, boron nitride, and the like. a powder; a bead formed by spheroidizing these inorganic fillers; a surface modification of these inorganic fillers; a single crystal fiber of these inorganic fillers; a glass fiber or the like.

Among these, the inorganic filler is preferably cerium oxide or aluminum oxide.

The filler (D) contained in the film for forming a protective film (III-1) and the film for forming a thermosetting protective film may be one type or two or more types. When two or more types are used, The combination and ratio of these can be arbitrarily selected.

In the case of using the filler (D), in the protective film-forming composition (III-1), the ratio of the content of the filler (D) to the total content of all components other than the solvent (that is, heat curing) The content of the filler (D) of the film for forming a protective film is preferably from 5% by mass to 80% by mass, more preferably from 7% by mass to 60% by mass. By setting the content of the filler (D) to such a range, it becomes easier to adjust the aforementioned coefficient of thermal expansion.

[coupler (E)]

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

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

Preferred examples of the decane coupling agent include 3-glycidoxypropyltrimethoxydecane, 3-glycidyloxypropylmethyldiethoxydecane, and 3-glycidyloxy group. Propyltriethoxydecane, 3-glycidyloxymethyldiethoxydecane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxydecane, 3-methylpropenyloxy Propyltrimethoxydecane, 3-aminopropyltrimethoxydecane, 3-(2-aminoethylamino)propyltrimethoxydecane, 3-(2-aminoethylamino)propane Methyldiethoxydecane, 3-(phenylamino)propyltrimethoxydecane, 3-anilinopropyltrimethoxydecane, 3-ureidopropyltriethoxydecane, 3-mercapto Propyltrimethoxydecane, 3-mercaptopropylmethyldimethoxydecane, bis(3-triethoxydecylpropyl)tetrasulfide, methyltrimethoxydecane, methyltriethoxy Decane, vinyltrimethoxydecane, vinyltriethoxydecane, imidazolium, and the like.

The coupling agent (III) and the thermosetting film forming film may be used alone or in combination of two or more kinds. In the case of two or more types, The combination and ratio of these can be arbitrarily selected.

In the case of using the coupling agent (E), the content of the coupling agent (E) in the film for protective film formation (III-1) and the film for forming a thermosetting protective film The total content of the polymer component (A) and the thermosetting component (B) is preferably from 0.03 parts by mass to 20 parts by mass, more preferably from 0.05 part by mass to 10 parts by mass, even more preferably 0.1 part by mass, per 100 parts by mass. Up to 5 parts by mass. When the content of the coupling agent (E) is at least the above lower limit value, the dispersibility of the filler (D) in the resin or the film in the film for forming a thermosetting protective film is further remarkably obtained. The effect of the use of the coupling agent (E) by the improvement of the adhesion of the body and the like. Further, by setting the content of the coupling agent (E) to be equal to or less than the above upper limit value, generation of outgas is further suppressed.

[crosslinking agent (F)]

When the polymer component (A) has a functional group such as a vinyl group, a (meth) acryl fluorenyl group, an amine group, a hydroxyl group, a carboxyl group or an isocyanate group which can be bonded to another compound, such as the acrylic resin. In the case of the film for forming a protective film (III-1) and the film for forming a thermosetting protective film, a crosslinking agent (F) for bonding the functional group to another compound to be crosslinked may be contained. By crosslinking with a crosslinking agent (F), the initial adhesion force and cohesive force of the film for thermosetting protective film formation can be adjusted.

Examples of the crosslinking agent (F) include an organic polyvalent isocyanate compound, an organic polyvalent quinone imine compound, a metal chelate-based crosslinking agent (a crosslinking agent having a metal chelate structure), and an aziridine-based crosslinking. A crosslinking agent (a crosslinking agent having an aziridine group) or the like.

Examples of the organic polyvalent isocyanate compound include an aromatic polyisocyanate compound, an aliphatic polyisocyanate compound, and an alicyclic polyisocyanate compound (hereinafter, these compounds may be simply referred to as "aromatic polyisocyanate compounds"). a trimer such as the aromatic polyvalent isocyanate compound, an isocyanurate or an adduct, and a terminal isocyanate urethane pre-form obtained by reacting the aromatic polyisocyanate compound or the like with a polyol compound. Polymer, etc. The term "adduct" means the aromatic polyvalent isocyanate compound, the aliphatic polyisocyanate compound or the alicyclic polyisocyanate compound, and is low with ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane or castor oil. The reactant containing the active hydrogen compound in the molecule, and examples thereof include a benzodimethyl diisocyanate adduct of trimethylolpropane as described below. Further, the "terminal isocyanate urethane prepolymer" is as described above.

As the above-mentioned organic polyvalent isocyanate compound, more specifically, for example, 2,4-toluene diisocyanate; 2,6-toluene diisocyanate; 1,3-benzenedimethyl diisocyanate; 1,4-dimethylbenzene Isocyanate; diphenylmethane-4,4'-diisocyanate; diphenylmethane-2,4'-diisocyanate; 3-methyldiphenylmethane diisocyanate; 1,6-hexamethylene diisocyanate; isophorone Diisocyanate; dicyclohexylmethane-4,4'-diisocyanate; dicyclohexylmethane-2,4'-diisocyanate; addition of toluene diisocyanate to all or a part of hydroxyl groups of a polyol such as trimethylolpropane, ,6-hexamethylene diisocyanate And a compound of any one or two or more kinds of benzodimethyl diisocyanate; an isocyanate diisocyanate or the like.

Examples of the organic polyvalent quinone imine compound include N,N'-diphenylmethane-4,4'-bis(1-aziridine carboxamide), and trimethylolpropane tris(β-nitrogen). Propionyl propionate), tetramethylol methane tris(β-aziridine propionate), N,N'-toluene-2,4-bis(1-aziridine carboxamide) Ethyl melamine and the like.

In the case where an organic polyvalent isocyanate compound is used as the crosslinking agent (F), as the polymer component (A), a hydroxyl group-containing polymer is preferably used. When the crosslinking agent (F) has an isocyanate group and the polymer component (A) has a hydroxyl group, it can be formed by reacting the crosslinking agent (F) with the polymer component (A) to form a thermosetting protective film. The crosslinked structure is simply introduced into the film.

The crosslinking agent (F) contained in the protective film-forming composition (III-1) and the film for forming a thermosetting protective film may be used alone or in combination of two or more kinds; in the case of two or more types The combinations and ratios of these can be arbitrarily selected.

In the case of using the crosslinking agent (F), in the protective film-forming composition (III-1), the content of the crosslinking agent (F) is preferably 100 parts by mass based on the content of the polymer component (A). It is from 0.01 part by mass to 20 parts by mass, more preferably from 0.1 part by mass to 10 parts by mass, even more preferably from 0.5 part by mass to 5 parts by mass. By making the content of the crosslinking agent (F) above the lower limit value, more prominently The effect produced by the use of the crosslinking agent (F) is obtained. In addition, when the content of the crosslinking agent (F) is at most the above-described upper limit, the adhesion to the support sheet in the film for forming a thermosetting protective film and the film for forming a thermosetting protective film are suppressed. The case where the bonding force with the semiconductor wafer or the semiconductor wafer is excessively lowered.

In the present invention, the effects of the present invention are sufficiently obtained even without using the crosslinking agent (F).

[Energy Curing Resin (G)]

The protective film forming composition (III-1) may further contain an energy ray-curable resin (G). The film for forming a thermosetting protective film can be changed in characteristics by irradiating an energy ray by containing an energy ray-curable resin (G).

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

The energy ray-curable compound may, for example, be a compound having at least one polymerizable double bond in the molecule, and is preferably an acrylate-based compound having a (meth) acrylonitrile group.

Examples of the acrylate-based compound include trimethylolpropane tri(meth)acrylate, tetramethylolmethanetetra(meth)acrylate, pentaerythritol tri(meth)acrylate, and pentaerythritol tetra(a). Acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol (A (meth) acrylate containing a chain aliphatic skeleton such as acrylate; (meth) acrylate containing a cyclic aliphatic skeleton such as dicyclopentyl bis(meth)acrylate; polyethylene glycol II Polyalkylene glycol (meth) acrylate such as (meth) acrylate; oligoester (meth) acrylate; (meth) acrylate urethane oligomer; epoxy modified (methyl) An acrylate; a polyether (meth) acrylate other than the above polyalkylene glycol (meth) acrylate; an itaconic acid oligomer or the like.

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

The energy ray-curable compound to be used for the polymerization may be one type or two or more types. When two or more types are used, the combination and ratio of these may be arbitrarily selected.

The energy ray-curable resin (G) contained in the protective film-forming composition (III-1) may be one type or two or more types. When two or more types are used, the combinations and ratios thereof may be Choose arbitrarily.

In the protective film-forming composition (III-1), the content of the energy ray-curable resin (G) is preferably from 1% by mass to 95% by mass, more preferably from 2% by mass to 90% by mass, particularly preferably Mass% to 85% by mass.

[Photopolymerization initiator (H)]

When the energy ray-curable resin (G) is contained, the protective film-forming composition (III-1) may contain a photopolymerization initiator in order to efficiently carry out the polymerization reaction of the energy ray-curable resin (G). (H).

The photopolymerization initiator (H) in the composition for forming a protective film (III-1) is the same as the photopolymerization initiator in the adhesive composition (ii).

The photopolymerization initiator (H) contained in the composition for forming a protective film (III-1) may be one type or two or more types. When two or more types are used, the combination and ratio of these may be Choose arbitrarily.

In the composition (III-1) for forming a protective film, the content of the photopolymerization initiator (H) is preferably from 0.1 part by mass to 20 parts by mass based on 100 parts by mass of the content of the energy ray-curable resin (G). More preferably, it is 1 part by mass to 10 parts by mass, and particularly preferably 2 parts by mass to 5 parts by mass.

[Colorant (I)]

The protective film forming composition (III-1) and the thermosetting protective film forming film may further contain a coloring agent (I).

The coloring agent (I) is, for example, a known one such as an inorganic pigment, an organic pigment, or an organic dye.

Examples of the organic pigment and the organic dye include an ammonium dye, a cyanine dye, a merocyanine dye, a ketone oxime dye, a squalene ruthenium dye, an anthraquinone dye, and a polymethine. Base dye, naphthoquinone dye, pyranthene dye, phthalocyanine dye, naphthalocyanine dye, naphthalene amide dye, azo dye, condensed azo dye, indigo dye, fluorenone Pigment, anthraquinone dye, dioxazine dye, quinacridone dye, isoindolinone dye, quinophthalone dye, pyrrole dye, thioindigo dye, metal complex dye (metal mismatched salt dye), dithiol metal complex dye, decyl phenol dye, triallyl methane dye, anthrone dye, dioxazine dye, naphthol dye, azo A methine-based dye, a benzimidazolone-based dye, a dermoside-based dye, or a Shihlin-based dye.

Examples of the inorganic pigment include carbon black, a cobalt dye, an iron dye, a chromium dye, a titanium dye, a vanadium dye, a zirconium dye, a molybdenum dye, an anthraquinone dye, a platinum dye, and ITO. (Indium Tin Oxide; indium tin oxide) dye, ATO (Antimony Tin Oxide) pigment, and the like.

The coloring agent (I) to be contained in the protective film-forming composition (III-1) and the film for forming a thermosetting protective film may be one type or two or more types. When two or more types are used, The combination and ratio of these can be arbitrarily selected.

When the coloring agent (I) is used, the content of the coloring agent (I) of the film for forming a thermosetting protective film may be appropriately adjusted depending on the purpose. For example, the protective film may be subjected to printing by laser irradiation, and the printing can be adjusted by adjusting the content of the coloring agent (I) of the film for forming a thermosetting protective film, adjusting the light transmittance of the protective film. Visual. In addition, the design of the protective film can be improved by adjusting the content of the coloring agent (I) of the film for forming a thermosetting protective film, or the polishing marks on the back surface of the semiconductor wafer can be made difficult to see. In view of the above, in the protective film-forming 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, the film for forming a thermosetting protective film) The content of the coloring agent (I) is preferably from 0.1% by mass to 10% by mass, more preferably from 0.1% by mass to 7.5% by mass, even more preferably from 0.1% by mass to 5% by mass. By setting the content of the coloring agent (I) to be equal to or higher than the above lower limit value, the effect by the use of the coloring agent (I) can be more remarkably obtained. In addition, when the content of the coloring agent (I) is at most the above upper limit value, excessive reduction in light transmittance of the film for forming a thermosetting protective film is suppressed.

[General Additives (J)]

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

The general additive (J) is preferably a known one, and can be arbitrarily selected according to the purpose, and is not particularly limited. Preferred examples thereof include a plasticizer, an antistatic agent, an antioxidant, and a deaerator.

The protective film-forming composition (III-1) and the film for forming a thermosetting protective film may be used alone or in combination of two or more kinds. The combination and ratio of these can be arbitrarily selected.

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

[solvent]

The protective film forming composition (III-1) preferably further contains a solvent. The composition (III-1) for forming a protective film containing a solvent is excellent in handleability.

The solvent is not particularly limited, and examples thereof include hydrocarbons such as toluene and xylene; methanol, ethanol, 2-propanol, isobutanol (2-methylpropan-1-ol), and 1-butyl. Alcohols such as alcohol; esters such as ethyl acetate and butyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; decylamines such as dimethylformamide and N-methylpyrrolidone (having a guanamine bond) Compound) and the like.

The solvent contained in the protective film-forming composition (III-1) may be one type or two or more types. When two or more types are used, the combination and ratio of these may be arbitrarily selected.

The solvent contained in the protective film-forming composition (III-1) is preferably methyl ethyl ketone, in that the component contained in the protective film-forming composition (III-1) is more uniformly mixed. Wait.

<<Method for Producing Composition for Forming Thermosetting Protective Film>>

The composition for forming a thermosetting protective film such as the protective film-forming composition (III-1) is obtained by blending the components constituting the composition.

The order of addition of each component is not particularly limited, and two or more components may be simultaneously added.

When a solvent is used, the compounding component may be previously diluted by mixing the solvent with any of the components, or may be diluted without preliminarily diluting any of the components other than the solvent. It is used by mixing a solvent with these compounding ingredients.

The method of mixing the components at the time of preparation is not particularly limited, and a method of mixing by stirring a stirring bar or a stirring blade, a method of mixing using a mixer, and a method of applying ultrasonic waves for mixing are appropriately selected. Just fine.

The temperature and time of each component to be added and mixed are not particularly limited as long as the respective components do not deteriorate, and the temperature may be appropriately adjusted, and the temperature is preferably from 15 ° C to 30 ° C.

‧Energy line curable protective film forming film

The film for forming an energy ray-curable protective film contains the energy ray-curable component (a).

The energy ray curable component (a) is preferably uncured, preferably has adhesiveness, more preferably uncured and has adhesiveness. Here, the "energy line" and the "energy line curability" are as described above.

<<Energy line curable protective film forming composition>>

The film for forming an energy ray-curable protective film can be formed using a composition for forming an energy ray-curable protective film containing the constituent material. For example, a composition for forming an energy ray-curable protective film can be applied to a surface to be formed of a film for forming an energy ray-curable protective film, and if necessary, dried to form an energy ray-curable protective film at a target portion. Use a membrane. The ratio of the content of the components which are not vaporized at normal temperature in the energy ray-curable protective film-forming composition is usually the same as the ratio of the components of the energy ray-curable protective film-forming film. Here, the "normal temperature" is as described above.

The application of the energy ray-curable protective film-forming composition may be carried out by a known method, and examples thereof include an air knife coater, a knife coater, a bar coater, a gravure coater, and a roll type. Coating machine, roll coater, curtain coater, die coater, knife coater, screen coater, wire bar coater, staple coater, etc. The method of cloth machine.

The drying condition of the energy ray-curable protective film-forming composition is not particularly limited, and when the energy ray-curable protective film-forming composition contains the following solvent, it is preferably dried by heating and drying. For example, it is preferably dried at 70 ° C to 130 ° C for 10 seconds to 5 minutes.

<Protective film forming composition (IV-1)>

The energy ray-curable protective film-forming composition, for example, the energy ray-curable protective film-forming composition (IV-1) containing the energy ray-curable component (a) (in the present specification, sometimes referred to as a short name) It is "the composition (IV-1) for protective film formation").

[Energy curing component (a)]

The energy ray-curable component (a) is a component which is cured by irradiation with an energy ray, and is a component for imparting film-forming property or flexibility to the film for forming an energy ray-curable protective film.

Examples of the energy ray-curable component (a) include a polymer (a1) having an energy ray-curable group having a weight average molecular weight of 80,000 to 2,000,000, and a compound having an energy ray-curable group having a molecular weight of 100 to 80,000. (a2). The polymer (a1) may be obtained by crosslinking at least a part of the polymer with a crosslinking agent, or may be one in which crosslinking is not carried out.

(Polymer (a1) having an energy-line-curable group having a weight average molecular weight of 80,000 to 2,000,000)

The polymer (a1) having a weight average molecular weight of 80,000 to 2,000,000 having an energy ray-curable group, for example, an acrylic polymer (a11) having a functional group capable of reacting with a group of another compound, An acrylic resin (a1-1) obtained by addition reaction with an energy ray-curable compound (a12) having an energy ray-curable group such as a group reactive with the functional group and 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 carboxyl group, an amine group, and a substituted amine group (one or two hydrogen atoms of the amine group are substituted with a group other than a hydrogen atom) A base, an epoxy group, and the like. Among them, in terms of preventing corrosion of a circuit such as a semiconductor wafer or a semiconductor wafer, the functional group is preferably a group other than a carboxyl group.

Among these, the aforementioned functional group is preferably a hydroxyl group.

‧Acrylic polymer with functional group (a11)

The acrylic polymer (a11) having the functional group may, for example, be an acrylic monomer having the functional group and an acrylic monomer having no functional group, or may be In addition to these monomers, a monomer other than the acrylic monomer (non-acrylic monomer) is further copolymerized.

Further, the acrylic polymer (a11) may be a random copolymer or a block copolymer.

Examples of the acrylic monomer having the functional group include a hydroxyl group-containing monomer, a carboxyl group-containing monomer, an amine group-containing monomer, a substituted amine 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, and (meth)acrylic acid 3- Hydroxypropyl ester, 2-hydroxyl (meth)acrylate a hydroxyalkyl (meth) acrylate such as butyl acrylate, 3-hydroxybutyl (meth) acrylate or 4-hydroxybutyl (meth) acrylate; non-(meth)acrylic unsaturated such as vinyl alcohol or allyl alcohol An alcohol (an unsaturated alcohol having no (meth) acrylonitrile skeleton) or the like.

Examples of the carboxyl group-containing monomer include an ethylenically unsaturated monocarboxylic acid (such as a monocarboxylic acid having an ethylenically unsaturated bond) such as (meth)acrylic acid or crotonic acid; and fumaric acid and itaconol. An ethylenically unsaturated dicarboxylic acid (dicarboxylic acid having an ethylenically unsaturated bond) such as an acid, a maleic acid or a methyl maleic acid; an acid anhydride of the above ethylenically unsaturated dicarboxylic acid; methacrylic acid A carboxyalkyl (meth)acrylate such as 2-carboxyethyl ester.

The acrylic monomer having the above functional group is preferably a hydroxyl group-containing monomer or a carboxyl group-containing monomer, more preferably a hydroxyl group-containing monomer.

The acrylic monomer having the functional group of the acrylic polymer (a11) may be one type or two or more types. When two or more types are used, the combination and ratio may be arbitrarily selected. .

Examples of the acrylic monomer having no such functional group include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, and isopropyl (meth)acrylate. Ester, n-butyl (meth)acrylate, isobutyl (meth)acrylate, second butyl (meth)acrylate, tert-butyl (meth)acrylate, amyl (meth)acrylate, (A) Acetyl hexyl acrylate, Heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-decyl (meth)acrylate, (methyl) Isodecyl acrylate, decyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate (lauryl (meth) acrylate), (meth) acrylate Tridecyl ester, tetradecyl (meth)acrylate (myristyl (meth)acrylate), pentadecyl (meth)acrylate, cetyl (meth)acrylate ((A) Alkyl group consisting of palmitic acid acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate (stearyl (meth) acrylate), etc. A (meth)acrylic acid alkyl ester or the like having a chain structure of 18.

Further, examples of the acrylic monomer having no such functional group include methoxymethyl (meth)acrylate, methoxyethyl (meth)acrylate, and ethoxylated (meth)acrylate. (A) alkoxyalkyl group-containing (meth) acrylate such as ester or ethoxyethyl (meth) acrylate; and aromatic (meth) acrylate such as phenyl (meth) acrylate Group-based (meth) acrylate; non-crosslinkable (meth) acrylamide and its derivatives; (meth)acrylic acid N,N-dimethylaminoethyl ester, (meth)acrylic acid N A (meth) acrylate having a non-crosslinkable tertiary amino group such as N-dimethylaminopropyl ester.

The acrylic monomer constituting the acrylic polymer (a11) which does not have the functional group may be one type or two or more types. In the case of two or more types, the combination and ratio may be arbitrarily select.

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 one type or two or more types. When two or more types are used, the combination and ratio may be arbitrarily selected.

In the acrylic polymer (a11), the ratio (content) of the amount of the constituent units derived from the acrylic monomer having the functional group is preferably 0.1% by mass based on the total amount of the constituent units constituting the acrylic polymer (a11). It is 50% by mass, more preferably 1% by mass to 40% by mass, and particularly preferably 3% by mass to 30% by mass. In the acrylic resin (a1-1) obtained by copolymerization of the acrylic polymer (a11) and the energy ray-curable compound (a12), the energy ray is obtained by the copolymerization of the acrylic polymer (a11) and the energy ray-curable compound (a12). The content of the curable group becomes easy to adjust the degree of curing of the protective film to a preferable range.

The acrylic polymer (a11) constituting the acrylic resin (a1-1) may be one type or two or more types. When two or more types are used, the combinations and ratios thereof may be arbitrarily selected. .

In the protective film-forming composition (IV-1), the content of the acrylic resin (a1-1) is preferably from 1% by mass to 40% by mass, more preferably from 2% by mass to 30% by mass, particularly preferably Mass% to 20% by mass.

‧Energy line curable compound (a12)

The energy ray-curable compound (a12) preferably has one or more selected from the group consisting of an isocyanate group, an epoxy group, and a carboxyl group, and is capable of functioning with the acrylic polymer (a11). The base on which the reaction is carried out is more preferably an isocyanate group as the aforementioned base. When the energy ray-curable compound (a12) has an isocyanate group as the above-mentioned group, for example, the isocyanate group is easily reacted with the hydroxyl group of the acrylic polymer (a11) having a hydroxyl group as the functional group.

The energy ray-curable compound (a12) preferably has one to five of the energy ray-curable groups in one molecule, and more preferably has one to two.

Examples of the energy ray-curable compound (a12) include 2-methylpropenyloxyethyl isocyanate, iso-isopropenyl-α,α-dimethylbenzyl ester, and methacrylic acid. Mercaptoisocyanate, allyl isocyanate, 1,1-bis(acryloxymethyl)ethyl isocyanate; by diisocyanate compound or polyisocyanate compound, and hydroxyethyl (meth) acrylate The acrylonitrile monoisocyanate compound obtained by the reaction; the acrylonitrile monoisocyanate compound obtained by the reaction of a diisocyanate compound, a polyisocyanate compound, a polyol compound, and hydroxyethyl (meth)acrylate.

Among these, the energy ray-curable compound (a12) is preferably 2-methylpropenyloxyethyl isocyanate.

The energy ray-curable compound (a12) constituting the acrylic resin (a1-1) may be one type or two or more types. When two or more types are used, the combination and ratio may be arbitrarily select.

In the acrylic resin (a1-1), the content of the energy ray-curable group derived from the energy ray-curable compound (a12) is based on the content of the functional group derived from the acrylic polymer (a11). The ratio is preferably from 20 mol% to 120 mol%, more preferably from 35 mol% to 100 mol%, still more preferably from 50 mol% to 100 mol%. By setting the ratio of the above content to such a range, the adhesion force of the cured protective film becomes larger. In the case where the energy ray-curable compound (a12) is a monofunctional (one group having one group in one molecule) compound, the upper limit of the ratio of the content is 100 mol%, but the energy ray is cured. When the compound (a12) is a compound having a polyfunctionality (having two or more of the above-mentioned groups in one molecule), the ratio of the above content is not more than 100 mol%.

The weight average molecular weight (Mw) of the aforementioned polymer (a1) is preferably from 100,000 to 2,000,000, more preferably from 300,000 to 1,500,000.

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

In the case where the polymer (a1) is at least partially crosslinked by a crosslinking agent, the polymer (a1) may be the one not described as a constituent of the acrylic polymer (a11). Any of the bodies Further, the monomer having a group reactive with the crosslinking agent is polymerized and crosslinked at a group reactive with the crosslinking agent, and may be derived from the energy ray-curable compound (a12). The group in which the aforementioned functional group is reacted is crosslinked.

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

(Compound (a2) having an energy ray-curable group having a molecular weight of 100 to 80,000)

The energy ray-curable group of the compound (a2) having a molecular weight of 100 to 80,000 having an energy ray-curable group may, for example, be a group containing an energy ray-curable double bond, and preferably, (methyl) ) acryl oxime, vinyl, and the like.

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

The low molecular weight compound having an energy ray-curable group in the compound (a2) may, for example, be a polyfunctional monomer or oligomer, and is preferably an acrylate compound having a (meth) acrylonitrile group.

Examples of the acrylate-based compound include 2-hydroxy-3-(meth)acryloxypropyl methacrylate, polyethylene glycol di(meth)acrylate, and propoxylated ethoxylate. Bisphenol A di(meth)acrylate, 2,2-bis[4-((meth)propenyloxypolyethoxy)phenyl]propane, ethoxylated bisphenol A di(methyl) Acrylate, 2,2-bis[4-((meth)propenyloxydiethoxy)phenyl]propane, 9,9-bis[4-(2-(methyl)propenyloxy) Ethoxy)phenyl]anthracene, 2,2-bis[4-((meth)propenyloxypolypropoxy)phenyl]propane, tricyclodecane dimethanol di(meth)acrylate, 1,10-nonanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, dipropylene glycol di(a) Acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylic acid Ester, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, 2,2-bis[4-((meth)acryloxyethoxy)phenyl] Propane, new Difunctional (meth)acrylic acid such as diol di(meth)acrylate, ethoxylated polypropylene glycol di(meth)acrylate, 2-hydroxy-1,3-bis(methyl)propenyloxypropane Ester; tris(2-(methyl)propenyloxyethyl)isophthalocyanate, ε-caprolactone modified tris(2-(methyl)propenyloxyethyl) Ester, ethoxylated glycerol tri(meth) acrylate, pentaerythritol tri(meth) acrylate, trimethylolpropane tri(meth) acrylate, bis(trimethylolpropane) tetra (methyl) Acrylate, ethoxylated pentaerythritol tetra(meth) acrylate, penta Polyfunctional (meth) acrylate such as tetraol tetra(meth) acrylate, dipentaerythritol poly(meth) acrylate, dipentaerythritol hexa (meth) acrylate; (meth) acrylate urethane oligo A polyfunctional (meth) acrylate oligomer such as a polymer.

The epoxy resin having an energy ray-curable group and the phenol resin having an energy ray-curable group in the compound (a2) can be, for example, described in paragraph 0043 of "Japanese Patent Laid-Open Publication No. 2013-194102". By. Such a resin is also a resin constituting the thermosetting component described below, but is considered as the above compound (a2) in the present invention.

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

The compound (a2) to be contained in the film for forming a protective film (IV-1) and the film for forming an energy ray-curable protective film may be one type or two or more types. When two or more types are used, The combinations and ratios of these can be arbitrarily selected.

[Polymer without energy ray-curable group (b)]

When the film for forming a protective film (IV-1) and the film for forming an energy ray-curable protective film contain the compound (a2) as the energy ray-curable component (a), it is preferable to further contain Energy ray-curable group polymer (b).

The polymer (b) may be formed by crosslinking at least a part thereof with a crosslinking agent or may be not 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 urethane urethane resin. Wait.

Among these, the polymer (b) is preferably an acrylic polymer (hereinafter, simply referred to as "acrylic polymer (b-1)").

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

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

Examples of the alkyl (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, and isopropyl (meth)acrylate. N-butyl acrylate, (meth) acrylate Butyl ester, second butyl (meth)acrylate, tert-butyl (meth)acrylate, amyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, (methyl) ) 2-ethylhexyl acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, (meth)acrylic acid Anthracene ester, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauryl (meth)acrylate), tridecyl (meth)acrylate, (meth)acrylic acid Myristyl ester (myristyl (meth)acrylate), pentadecyl (meth)acrylate, cetyl (meth)acrylate (palmityl (meth)acrylate), (methyl) The alkyl group constituting the alkyl ester such as cetyl acrylate or octadecyl (meth) acrylate (stearyl (meth) acrylate) is a chain structure having a carbon number of 1 to 18 (methyl) Alkyl acrylate and the like.

Examples of the (meth) acrylate having a cyclic skeleton include, for example, isobornyl (meth)acrylate and cycloalkyl (meth)acrylate such as dicyclopentyl (meth)acrylate; (alkyl) methacrylate such as benzyl acrylate; cycloalkyl alkenyl (meth) acrylate such as dicyclopentenyl (meth)acrylate; dicyclopenteneoxy (meth) acrylate A cyclomethallyl alkyl (meth)acrylate or the like.

Examples of the glycidyl group-containing (meth) acrylate include glycidyl (meth)acrylate and the like.

Examples of the hydroxyl group-containing (meth) acrylate include hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and (methyl). ) 3-hydroxypropyl acrylate, (meth) propyl 2-hydroxybutyl acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and the like.

Examples of the (meth) acrylate containing a substituted amino group include N-methylaminoethyl (meth) acrylate and the like.

The non-acrylic monomer constituting the acrylic polymer (b-1) may, for example, be an olefin such as ethylene or norbornene; vinyl acetate; styrene or the like.

The polymer (b) having no energy ray-curable group which is obtained by crosslinking at least a part of a crosslinking agent, for example, may be a reaction of a reactive functional group in the polymer (b) with a crosslinking agent. Made.

The reactive functional group is not particularly limited as long as it is appropriately selected depending on the type of the crosslinking agent and the like. For example, when the crosslinking agent is a polyisocyanate compound, the reactive functional group may, for example, be a hydroxyl group, a carboxyl group or an amine group, and among these, a hydroxyl group having high reactivity with an isocyanate group is preferred. In the case where the crosslinking agent is an epoxy compound, the reactive functional group may, for example, be a carboxyl group, an amine group or a guanamine group, and among these, a carboxyl group having high reactivity with an epoxy group is preferred. . Among them, in terms of preventing corrosion of a circuit of a semiconductor wafer or a semiconductor wafer, the reactive functional group is preferably a group other than a carboxyl group.

As the polymer (b) having the aforementioned reactive functional group and having no energy ray-curable group, for example, at least the aforementioned reactive officer is mentioned The monomer of the energy base is obtained by polymerization. In the case of the acrylic polymer (b-1), any one of the acrylic monomer and the non-acrylic monomer exemplified as the monomer constituting the monomer having the reactive functional group or Both. For example, the polymer (b) having a hydroxyl group as a reactive functional group may be obtained by polymerizing a hydroxyl group-containing (meth) acrylate, and the above-mentioned acrylic acid may be mentioned. A monomer obtained by substituting one or more hydrogen atoms of the monomer or non-acrylic monomer with the reactive functional group is polymerized.

In the above polymer (b) having a reactive functional group, the ratio (content) of the amount of the constituent unit derived from the monomer having a reactive functional group is preferably relative to the total amount of constituent units constituting the functional group. 1% by mass to 20% by mass, more preferably 2% by mass to 10% by mass. By making the aforementioned ratio into such a range, the degree of crosslinking in the above 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 10,000 to 10,000 in terms of the film forming property of the protective film-forming composition (IV-1). 2000000, more preferably 100000 to 1.500000. Here, the "weight average molecular weight" is as described above.

The polymer (b) having no energy ray-curable group contained in the film for protective film formation (IV-1) and the film for forming an energy ray-curable protective film may be used only In the case of two or more kinds, the combination and ratio of these may be arbitrarily selected.

The composition (IV-1) for forming a protective film may be a composition containing either or both of the polymer (a1) and the compound (a2). Further, when the protective film-forming composition (IV-1) contains the compound (a2), it is preferred to further contain the polymer (b) having no energy ray-curable group, and in this case, It is preferable to further contain the aforementioned (a1). In addition, the protective film-forming composition (IV-1) may not contain the compound (a2), and may contain the polymer (a1) and the polymer (b) having no energy ray-curable group.

When the protective film-forming composition (IV-1) contains the polymer (a1), the compound (a2), and the polymer (b) having no energy ray-curable group, the composition for forming a protective film In the above (IV-1), the content of the compound (a2) is preferably 10 parts by mass based on 100 parts by mass of the total of the polymer (a1) and the polymer (b) having no energy ray-curable group. 400 parts by mass, more preferably 30 parts by mass to 350 parts by mass.

In the composition (IV-1) for forming a protective film, the total content of the energy ray-curable component (a) and the polymer (b) having no energy ray-curable group (b) in terms of the total content of components other than the solvent The ratio (that is, the total content of the energy ray-curable component (a) and the polymer (b) having no energy ray-curable group in the film for forming an energy ray-curable protective film) is preferably 5 The amount is from 90% by mass, more preferably from 10% by mass to 80% by mass, even more preferably from 20% by mass to 70% by mass. When the ratio of the content of the energy ray-curable component is in such a range, the energy ray curability of the film for forming an energy ray-curable protective film is further improved.

The protective film-forming composition (IV-1) may contain, in addition to the energy ray-curable component, a thermosetting component, a photopolymerization initiator, a filler, a coupling agent, a crosslinking agent, and a coloring agent, depending on the purpose. One or two or more of the group consisting of a general agent and a general-purpose additive. For example, the film for forming an energy ray-curable protective film formed by using the protective film-forming composition (IV-1) containing the energy ray-curable component and the thermosetting component is heated by heating. The strength of the protective film formed by the film for forming an energy ray-curable protective film is also improved by increasing the adhesion to the adherend.

The thermosetting component, the photopolymerization initiator, the filler, the coupling agent, the crosslinking agent, the coloring agent, and the general-purpose additive in the composition for forming a protective film (IV-1) are each used for forming a protective film. Thermosetting component (B), photopolymerization initiator (H), filler (D), coupling agent (E), crosslinking agent (F), coloring agent (I) in composition (III-1) And the general additive (J) is the same.

In the protective film-forming composition (IV-1), the thermosetting component, the photopolymerization initiator, the filler, the coupling agent, the crosslinking agent, the coloring agent, and the general-purpose additive may be used singly or in combination. Use two or more types together, When two or more types are used in combination, the combination and ratio of these can be arbitrarily selected.

The content of the thermosetting component, the photopolymerization initiator, the filler, the coupling agent, the crosslinking agent, the coloring agent, and the general-purpose additive in the protective film-forming composition (IV-1) is appropriately adjusted according to the purpose. There is no special limit.

The protective film-forming composition (IV-1) is preferably further contained in a solvent because it is improved in workability by dilution.

The solvent contained in the protective film-forming composition (IV-1) is, for example, the same as the solvent in the protective film-forming composition (III-1).

The solvent contained in the protective film-forming composition (IV-1) may be one type or two or more types.

<<Method for Producing Composition for Energy-Line Curable Protective Film Formation>>

The energy ray curable protective film forming composition such as the protective film forming composition (IV-1) is obtained by blending the components constituting the composition.

The order of addition of each component is not particularly limited, and two or more components may be simultaneously added.

When a solvent is used, the solvent may be mixed with any of the components other than the solvent, and the formulation may be diluted beforehand, or the solvent may be mixed with any of the components other than the solvent. Mix and use.

The method of mixing the components at the time of preparation is not particularly limited, and a method of mixing by stirring a stirring bar or a stirring blade, a method of mixing using a mixer, and a method of applying ultrasonic waves for mixing are appropriately selected. Just fine.

The temperature and time of each component to be added and mixed are not particularly limited as long as the respective components do not deteriorate, and the temperature may be appropriately adjusted, and the temperature is preferably from 15 ° C to 30 ° C.

○ coating layer

As the coating layer, for example, a cured product obtained by curing by irradiation with an energy ray is preferably used, and it is preferred to cure the coating composition containing an energy ray polymerizable compound polymerized by irradiation with an energy ray. And the winner. Further, the energy ray polymerizable compound is preferably (meth)acrylic acid or a derivative thereof.

The composite sheet for forming a protective film can be made not only to have a function of forming a protective film for protecting the back surface of the semiconductor wafer obtained by dicing, but also as a function of a dicing sheet for cutting a semiconductor wafer. Further, when the semiconductor wafer is diced, the semiconductor wafer to which the composite sheet for forming a protective film is attached may be stretched. In this case, the composite sheet for forming a protective film is required to have appropriate flexibility. In order to impart appropriate flexibility to the composite sheet for forming a protective film, for example, a soft resin such as polypropylene may be selected as the material constituting the support sheet. On the other hand, such a soft resin or the like may be deformed by heating or wrinkles may occur. Therefore, think of painting The cloth layer is desirably formed by curing the composition of the raw material by irradiation of energy rays instead of heat curing.

The thickness of the coating layer is not particularly limited, and is preferably from 0.1 μm to 20 μm, more preferably from 0.4 μm to 15 μm, still more preferably from 0.8 μm to 10 μm. When the thickness of the coating layer is at least the above lower limit value, the surface roughness Ra of the surface on the side opposite to the side contacting the support sheet in the coating layer is more easily lowered, and the formation of the protective film is suppressed. The adhesion of the composite sheet becomes more effective. In addition, when the thickness of the coating layer is equal to or less than the above-described upper limit, it is possible to obtain a state in which the semiconductor wafer to which the protective film forming composite sheet is attached is inspected by an infrared camera or the like via the sheet. Clear inspection images and, in addition, easier cutting of semiconductor wafers with extensions.

Further, the coating layer covers the uneven surface of the support sheet as described above, and the contact surface with the support sheet becomes an uneven surface, and the thickness of the coating layer includes the convex portion on the uneven surface of the coating layer. The position may be calculated by using the tip end of the convex portion as a starting point.

The surface roughness Ra of the surface of the coating layer opposite to the side contacting the support sheet is preferably 0.5 μm or less, more preferably 0.4 μm or less, further preferably 0.3 μm or less, and particularly preferably 0.2 μm or less. . By setting the surface roughness Ra of the coating layer to be equal to or less than the above upper limit value, it is possible to perform laser printing more clearly on the protective film.

In addition, the lower limit of the surface roughness Ra of the surface on the side opposite to the side contacting the support sheet in the coating layer is not particularly limited, and may be, for example, 0.005 μm or the like.

The surface roughness Ra of the coating layer can be, for example, the surface roughness Ra of the surface of the support sheet on the side having the coating layer, the thickness of the coating layer, and the following coating composition for forming the coating layer. Adjustment is performed by a coating method or the like.

With respect to the coating layer, the value of [the thickness of the coating layer (μm)] / [the surface roughness Ra (μm) of the surface of the support sheet having the coating layer side) is preferably from 0.1 to 30, more preferably From 0.3 to 20, particularly preferably from 0.5 to 10. By setting the value to be equal to or higher than the lower limit value, the surface roughness Ra of the surface on the side opposite to the side contacting the support sheet in the coating layer becomes smaller, and the laser film can be more clearly performed on the protective film. In addition, the effect of suppressing the adhesion of the above-mentioned composite sheet for forming a protective film becomes higher. Further, by setting the value to be equal to or less than the above upper limit value, the thickness of the coating layer is prevented from becoming excessive.

The gloss value of the surface of the coating layer opposite to the side contacting the side of the support sheet (the side of the support sheet) is preferably from 32 to 95, more preferably from 40 to 90, still more preferably from 45 to 85. By setting the aforementioned glossiness of the coating layer to such a range, it is possible to perform laser printing more clearly on the protective film.

In addition, when the glossiness of the coating layer is equal to or greater than the lower limit value, the state of the semiconductor wafer to which the protective film forming composite sheet is attached is inspected by an infrared camera or the like through the sheet, Get more clear Clearly check the image. In addition, when the glossiness of the coating layer is equal to or less than the above upper limit value, when the state of the semiconductor wafer is inspected in the same manner, the phenomenon that the coating layer is brightened is suppressed, and it is easier to visually use an infrared camera or the like. The inspection image taken.

Further, the glossiness is a value obtained by measuring the 20° specular gloss of the surface of the coating layer from the side opposite to the side of the support sheet in the coating layer in accordance with JIS K 7105.

The measured value of the haze from the side of the coating layer in the composite sheet for forming a protective film is 47% or less, preferably 1% to 47%, more preferably 2% to 40%, still more preferably 3% to 30%. When the haze of the composite sheet for forming a protective film is equal to or less than the above upper limit value, scattering of light is suppressed, and laser printing can be performed more clearly on the protective film. In addition, when the state of the semiconductor wafer to which the protective film forming composite sheet is attached is inspected by an infrared camera or the like through the sheet, a clearer inspection image can be obtained.

Various characteristics such as the glossiness of the coating layer can be adjusted, for example, by the thickness of the coating layer, the component of the coating composition to be formed into a coating layer, and the like.

The measured value of the haze from the side of the coating layer in the composite sheet for forming a protective film can be, for example, the thickness of each layer of the composite sheet for forming a protective film by a coating layer or a support sheet, etc., for forming these layers. The composition (for example, the coating composition described below) contains components and the like to be adjusted.

<<Coating composition>>

The coating composition is preferably one or both of the cerium oxide sol and the cerium oxide microparticles bonded with the organic compound containing a radical polymerizable unsaturated group (α) (hereinafter) One or more (β) selected from the group consisting of a polyfunctional acrylate monomer and an acrylate prepolymer (hereinafter sometimes referred to simply as "component (α)") "Component (β)").

[ingredient (α)]

In the above-mentioned component (α), the refractive index of the coating layer is lowered, and the cured shrinkage property and the thermal wet shrinkability of the composite sheet for forming a protective film are lowered, and the composite sheet for forming a protective film due to the shrinkage is suppressed from occurring. The situation of curling.

Examples of the cerium oxide sol of the component (α) include colloidal cerium oxide in which a cerium oxide fine particle is suspended in an organic solvent such as an ether derived from ethylene glycol (cellosolve) in a colloidal state, and the suspension is as described above. The average particle diameter of the cerium oxide microparticles is preferably from 0.001 μm to 1 μm, more preferably from 0.03 μm to 0.05 μm.

The cerium oxide microparticles in which the component (α) is bonded to the organic compound containing a radical polymerizable unsaturated group is crosslinked and cured by irradiation of an energy ray.

Examples of the cerium oxide fine particles to which the radical polymerizable unsaturated group-containing organic compound is bonded include a sterol group in which the surface of the cerium oxide microparticles is present, and a radical polymerizable unsaturated group. The functional group in the organic compound is reacted, and the average particle diameter of the cerium oxide fine particles is preferably from 0.005 μm to 1 μm. The functional group in the radical polymerizable unsaturated group-containing organic compound is not particularly limited as long as it can react with the sterol group in the cerium oxide microparticles.

Examples of the organic compound containing a radical polymerizable unsaturated group having the above functional group include a compound represented by the following formula (1).

In the formula, R ¹ is a hydrogen atom or a methyl group; and R ² is a halogen atom or a group represented by any one of the following formulas (2a) to (2f).

Examples of the halogen atom of R ² include a chlorine element, a bromine atom, and an iodine atom.

Preferred examples of the radical polymerizable unsaturated group-containing organic compound include (meth)acrylic acid, (meth)acrylonitrile chloride, and 2-isocyanatoethyl (meth)acrylate. Glycidyl (meth)acrylate, 2,3-iminopropyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, (3-(methyl)acryloxypropyl) trimethyl Oxydecane, etc.

In the present invention, the above-mentioned organic compound containing a radically polymerizable unsaturated group may be used singly or in combination of two or more kinds.

In the component (α), the cerium oxide sol and the cerium oxide fine particles to which the organic compound containing a radical polymerizable unsaturated group are bonded may be used alone or in combination of two or more.

As the component (α), only the cerium oxide sol may be used, or only the cerium oxide microparticles to which the organic compound containing a radical polymerizable unsaturated group is bonded may be used, or the cerium oxide sol and the aforementioned bond may be used. The cerium oxide microparticles having an organic compound containing a radical polymerizable unsaturated group are used in combination.

The content of the component (α) of the coating composition is preferably selected according to the refractive index of the support sheet, and it is generally preferred that the content of the cerium oxide derived from the component (α) of the coating layer is 20 mass. % to 60% by mass. When the content of the cerium oxide is at least the above lower limit value, the effect of lowering the refractive index of the coating layer and the effect of suppressing curling of the composite sheet for forming a protective film become higher. In addition, when the content of the cerium oxide is at most the above upper limit value, the formation of the coating layer becomes easier, and the effect of suppressing the decrease in the hardness of the coating layer becomes higher.

The refractive index of the coating layer, the ease of formation and the hardness, and the suppression of occurrence of curl of the composite sheet for forming a protective film become better, and the coating layer is derived from the component (α) of cerium oxide. The content is more preferably from 20% by mass to 45% by mass.

[ingredient (β)]

The component (β) forms a main photocurable component of the coating layer.

The polyfunctional acrylate monomer of the component (β) is not particularly limited as long as it is a (meth)acrylic acid derivative having two or more (meth)acrylonyl groups in one molecule.

Preferred examples of the polyfunctional acrylate monomer include 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, and neopenta-2. Alcohol di(meth)acrylate, polyethylene glycol di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, di(a) Dicyclopentyl acrylate, caprolactone modified dicyclopentenyl di(meth) acrylate, ethylene oxide modified di(meth) acrylate, allylated cyclohexyl bis ( Methyl) acrylate, di(meth) acrylate, trimethylolpropane tri(meth) acrylate, dipentaerythritol tri(meth) acrylate, propionic acid modified dipentaerythritol III ( Methyl) acrylate, pentaerythritol tri(meth) acrylate, propylene oxide modified trimethylolpropane tri(meth) acrylate, isomeric isocyanuric acid tris(propylene oxy oxyethyl) ester, two Pentaerythritol penta (meth) acrylate, propionic acid modified dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, caprolactone modified dipentaerythritol hexa (meth) acrylate, and the like.

The acrylate-based prepolymer in the component (β) is not particularly limited as long as it is a photocurable polymer or oligomer due to (meth) acrylate.

Preferred examples of the acrylate-based prepolymer include a polyester acrylate prepolymer, an epoxy acrylate prepolymer, an urethane acrylate prepolymer, and a polyol acrylate prepolymer. Polymer, etc.

The polyester acrylate-based prepolymer is, for example, a hydroxyl group of a polyester oligomer having a hydroxyl group at both terminals of a molecule obtained by a condensation reaction of a polyvalent carboxylic acid and a polyhydric alcohol, using (meth)acrylic acid. The esterification is obtained by esterification of a terminal hydroxyl group of an oligomer obtained by an addition reaction of an alkylene oxide and a polyvalent carboxylic acid with (meth)acrylic acid.

The epoxy acrylate-based prepolymer is, for example, reacted with (meth)acrylic acid and a relatively low molecular weight bisphenol epoxy resin or a novolak epoxy resin oxirane ring. Esterification to obtain.

As the urethane-based prepolymer, for example, a polyurethane oligomer obtained by a reaction of a polyether polyol or a polyester polyol with a polyisocyanate can be used. Acrylic acid obtained by esterification.

The polyol acrylate-based prepolymer is obtained, for example, by esterification of a hydroxyl group of a polyether polyol with (meth)acrylic acid.

In the component (β), the polyfunctional acrylate monomer and the acrylate prepolymer may be used alone or in combination of two or more.

As the component (β), only the above-mentioned polyfunctional acrylate monomer may be used, or only the acrylate prepolymer may be used, or the polyfunctional acrylate monomer and acrylate prepolymer may be used. And use it.

[solvent]

The coating composition preferably further contains a solvent in addition to the component (α) and the component (β). By coating the coating composition with a solvent, the coating composition can be applied and dried as follows to easily form a coating film for forming a coating layer.

These solvents may be used alone or in combination of two or more.

Examples of the solvent include aliphatic hydrocarbons such as hexane, heptane, and cyclohexane; aromatic hydrocarbons such as toluene and xylene; halogenated hydrocarbons such as dichloromethane and dichloroethane; and methanol, ethanol, and propanol. An alcohol such as butanol or 1-methoxy-2-propanol; a ketone such as acetone, methyl ethyl ketone, 2-pentanone, isophorone or cyclohexanone; an ester of ethyl acetate or butyl acetate; - cellosolve such as ethoxyethanol (ethyl cellosolve).

[arbitrary ingredients]

The coating composition may contain, in addition to the component (α) and the component (β), a monofunctional acrylate monomer, a photopolymerization initiator, a photosensitizer, a polymerization inhibitor, insofar as the efficacy of the present invention is not impaired. Various components such as a crosslinking agent, an antioxidant, an ultraviolet absorber, a light stabilizer, a leveling agent, and an antifoaming agent.

The above-mentioned arbitrary components may be used alone or in combination of two or more.

(monofunctional acrylate monomer)

The monofunctional acrylate-based monomer which is an optional component is a photocurable component, and is not particularly limited as long as it is a (meth)acrylic acid derivative having only one (meth)acryl fluorenyl group in one molecule.

Preferred examples of the monofunctional acrylate-based monomer include cyclohexyl (meth)acrylate and 2-ethylhexyl (meth)acrylate. Base) lauryl acrylate (lauryl (meth) acrylate), octadecyl (meth) acrylate (stearyl (meth) acrylate), isobornyl (meth) acrylate, and the like.

(photopolymerization initiator)

The photopolymerization initiator which is an optional component is a well-known one which is used for radical polymerization.

Preferred examples of the photopolymerization initiator include an acetophenone-based compound, a benzophenone-based compound, an alkylaminobenzophenone-based compound, a benzoin-based compound, a benzoin-based compound, and a benzoin ether. An aryl ketone photopolymerization initiator such as a compound, a benzoin dimethyl acetal compound, a benzamidine benzoate compound or an α-mercapto oxime ester compound; a thioether compound; A sulfur-containing photopolymerization initiator such as a ketone compound; a mercaptophosphine oxide compound such as a mercapto diarylphosphine oxide; an anthrone compound.

Further, in the case where the aforementioned coating composition is cured by irradiation of an electron beam, a photopolymerization initiator is not required.

In the coating composition, the content of the photopolymerization initiator is preferably from 0.2 part by mass to 10 parts by mass, more preferably from 0.5 part by mass to 7 parts by mass, per 100 parts by mass of the total amount of the photocurable component.

(photosensitizer)

Examples of the photosensitizer include tertiary amines, p-dimethylaminobenzoic acid esters, and thiol-based sensitizers.

In the coating composition, the content of the photosensitizer is preferably from 1 part by mass to 20 parts by mass, more preferably from 2 parts by mass to 10 parts by mass, per 100 parts by mass of the total amount of the photocurable component.

(antioxidant, UV absorber, light stabilizer)

The antioxidant, the ultraviolet absorber, and the light stabilizer are preferably those known in the art, and are preferably a reactive antioxidant such as a (meth) acrylonitrile group in the molecule, an ultraviolet absorber, and a light stabilizer. Since these antioxidants, ultraviolet absorbers, and light stabilizers are bonded to a polymer chain formed by irradiation of energy rays, the function of these components is exhibited for a long period of time by suppressing escape of the self-cured layer over time.

The coating composition preferably contains a cerium oxide sol as a component (α), more preferably a cerium oxide sol having an average particle diameter of 0.03 μm to 0.05 μm containing cerium oxide microparticles suspended in a colloidal state. .

When the coating layer contains such a cerium oxide sol, the effect of suppressing the adhesion of the composite sheet for forming a protective film becomes higher. Further, in the coating layer, such a cerium oxide sol is more distributed than the other regions on the surface on the side opposite to the support sheet side and the vicinity thereof, and the distribution is uneven, and the composite sheet for forming a protective film is suppressed. The effect of adhesion is further increased. In order to unevenly distribute the components contained in the cerium oxide sol or the like in the coating layer, the coating conditions of the coating composition may be adjusted.

<<Manufacturing method of coating composition>>

The coating composition is obtained, for example, by blending an energy ray-polymerizable compound such as a component (α) and a component (β) with a component other than the component to form a coating composition. The coating composition is obtained, for example, by the same method as in the case of the above-described adhesive composition except that the formulation components are different.

When a solvent is used, it may be prepared by mixing a solvent and a solvent other than the solvent, and the compounding component may be diluted beforehand, or may be diluted without any solvent other than the solvent. The solvent is mixed with these compounding ingredients and used.

The components other than the solvent in the coating composition may be dissolved or may be dispersed without being dissolved. Further, the concentration and viscosity of each component of the coating composition are not particularly limited as long as the coating composition can be applied.

◎Manufacturing method of composite sheet for forming protective film

The composite sheet for forming a protective film of the present embodiment can be produced by forming a film for forming a protective film by using the composition for forming a protective film, forming a coating layer using the coating composition, and sequentially coating the film. The film layer, the support sheet, and the film for forming a protective film are laminated.

In the case where the support sheet contains a plurality of layers, these plural layers may be laminated to form a support sheet. For example, when the support sheet is formed by laminating a substrate and an adhesive, the adhesive composition may be used to form an adhesive layer.

The order of formation of each layer (coating layer, support sheet, and film for forming a protective film) constituting the composite sheet for forming a protective film is not particularly limited. Further, in the formation of the respective layers from the composition, the state in which the composite sheet for film formation can be protected is directly performed on the surface of the adjacent layer, and a release film (release sheet) may be additionally used on the surface, and the formation may be performed. The layer is bonded to the surface of the adjacent layer in the state of the composite sheet for forming a protective film. In the case where the surface (back surface) on the side opposite to the surface (surface) of the film for forming a protective film is a concave-convex surface, it is suppressed between the coating layer and the uneven surface (back surface) of the support sheet. In the case where the void portion is formed, it is preferred that the coating layer be formed by directly applying a coating composition to the uneven surface of the support sheet.

Hereinafter, an example of a preferred method for producing a composite sheet for forming a protective film will be described.

Preferably, the coating layer is coated with a coating composition by the uneven surface of the support sheet (the back surface 10b of the support sheet 10, that is, the back surface 11b of the substrate 11 in FIGS. 1 and 2), and dried. It is formed by curing a coating film formed as needed.

The coating of the coating composition on the surface of the object can be carried out by a known method, and examples thereof include an air knife coater, a knife coater, a bar coater, a gravure coater, and a roll coating. Machines, roll coaters, curtain coaters, die coaters, knife coaters, screen coaters, wire bar coaters, staple coaters, etc. The method.

In the case where the coating composition is applied to the uneven surface of the support sheet, it is preferable to suppress the occurrence of voids between the coating layer and the uneven surface of the support sheet. By suppressing the occurrence of the void portion, the diffuse reflection of light at the boundary between the coating layer and the uneven surface of the support sheet is suppressed, so that the laser printing can be performed more clearly on the surface of the protective film.

In order to suppress the occurrence of the aforementioned void portion, for example, a coating composition having a small viscosity is preferably used. Further, the coating composition containing the energy ray polymerizable compound is generally suitable for suppressing the generation of the aforementioned void portion.

The drying conditions of the coating composition are not particularly limited, and it is preferred to heat-dry the coating composition. In this case, for example, it is preferably dried at 70 ° C to 130 ° C for 0.5 minutes to 5 minutes. .

The curing conditions of the coating film formed from the coating composition are not particularly limited, and may be carried out by a known method.

In the case of curing by irradiation with an energy ray, for example, when ultraviolet ray is irradiated, a high pressure mercury lamp, a fused H lamp, a xenon lamp or the like is used as the ultraviolet ray source, and the irradiation amount is preferably 100 mJ/cm ^{2 .} It is sufficient to irradiate at 500 mJ/cm ² . On the other hand, in the case of irradiating an electron beam, an electron beam is generated by an electron beam accelerator or the like, and the irradiation amount is preferably 150 kV to 350 kV. Among them, the formation of the coating layer is preferably carried out by irradiation of ultraviolet rays.

In the case where the support sheet is formed by laminating a substrate and an adhesive, the adhesive layer may be directly on the surface of the substrate having the coating layer (the surface 11a of the substrate 11 in FIGS. 1 and 2). It is formed by applying an adhesive composition. However, it is generally preferred to employ a method in which an adhesive layer is additionally formed and adhered to the surface of the substrate, for example, the adhesive composition is applied to the release-treated surface of the release sheet and dried, whereby the adhesive is formed. The agent layer is attached to the surface of the substrate, and the release sheet or the like is removed.

The adhesive composition can be applied to the surface of the object by the same method as in the case of coating the composition.

The applied adhesive composition can be crosslinked by heating, and the crosslinking by heating can also serve as drying. The heating conditions can be, for example, 100 ° C to 130 ° C for 1 minute to 5 minutes, but are not limited thereto.

When the support sheet is a case where only one layer (single layer) is included in the substrate alone, and for example, when the substrate and the adhesive layer are laminated, the plurality of layers may be included. The surface of the support sheet of the coating layer (the surface 10a of the support sheet 10, that is, the surface 12a of the adhesive layer 12 in FIGS. 1 and 2) is directly coated with a composition for forming a protective film to form a protective film. Use a membrane. However, it is generally preferred to use a method of separately forming a film for forming a protective film and attaching it to the surface of the support sheet in the same manner as in the case of the above-mentioned adhesive layer, for example, by applying a protective coating on the release-treated surface of the release sheet. a film forming composition, which is dried to form a protective film The film for formation is bonded to the surface of the support sheet, and the release sheet or the like is removed as needed.

The composition for forming a protective film can be applied to the surface of the object by the same method as in the case of coating the composition.

The drying conditions of the composition for forming a protective film are not particularly limited, and it can be dried by the same method as in the case of coating the composition.

In the case where the support sheet is formed by laminating a substrate and an adhesive, the composite sheet for forming a protective film of the present invention can also be produced by a method other than the above. For example, the pressure-sensitive adhesive layer may be formed by using the pressure-sensitive adhesive composition, and the film for forming a protective film may be formed by using the protective film-forming composition, and then the pressure-sensitive adhesive layer and the film for forming a protective film may be laminated. The surface of the base material having the coating layer is bonded to the surface of the pressure-sensitive adhesive layer (the surface of the pressure-sensitive adhesive layer on which the film for forming a protective film is not provided) (in FIGS. 1 and 2, A surface 11a) of the substrate 11 is used to produce a composite sheet for forming a protective film.

In this case, the conditions for forming the adhesive layer and the film for forming a protective film are the same as those of the above method.

In the case where the surface (back surface) on the side opposite to the surface (surface) of the film for forming a protective film is not a concave-convex surface and is a smooth surface, the composite sheet for forming a protective film of the present embodiment may be used as described above. Manufactured by methods other than the method. For example, the coating can also be formed by using the aforementioned coating composition. The film layer is bonded to the smooth surface of the support sheet to form a laminate. On the other hand, the film for forming a protective film is formed by using the composition for forming a protective film in advance, and the film for forming a protective film is bonded to the film. The exposed surface of the support sheet of the laminate (the surface of the support sheet on which the coating layer is not provided) is used to produce a composite sheet for forming a protective film. The order of bonding the formed coating layer and the film for forming a protective film on the support sheet may be reversed as described above, and the film for forming a protective film may be attached to one surface of the support sheet on the other surface of the support sheet. (The surface of the support sheet on which the film for forming a protective film is not provided) The coating layer is bonded to each other to produce a composite sheet for forming a protective film.

In addition, the protective film forming film may be formed by using the protective film forming composition in advance on one surface of the support sheet, and the coating layer may be formed using the coating composition, and the coating layer may be formed. The composite sheet for forming a protective film is produced by being bonded to the exposed surface of the support sheet (the surface of the support sheet on which the film for forming a protective film is not provided).

The conditions for forming the coating layer and the film for forming a protective film in these cases are the same as those in the case of the above method.

For example, when manufacturing a composite sheet for forming a protective film, when the surface of the film for forming a protective film is smaller than the surface area of the adhesive layer, the composite film for forming a protective film is formed in the above-described manufacturing method, as shown in FIG. It is sufficient to provide a film for forming a protective film which has been previously cut into a predetermined size and shape on the adhesive layer.

◎How to use the composite film for forming a protective film

The method of using the composite sheet for forming a protective film of the present embodiment is as follows, for example.

First, a method of using the composite sheet for forming a protective film in the case where the film for forming a protective film is thermosetting will be described.

In this case, the back surface of the semiconductor wafer is attached to the film for forming a protective film of the composite sheet for forming a protective film, and the composite sheet for forming a protective film is fixed to the dicing apparatus.

Next, the film for forming a protective film is cured by heating to form a protective film. When the back surface polishing tape is attached to the surface (electrode forming surface) of the semiconductor wafer, the back surface polishing tape is usually removed from the semiconductor wafer to form a protective film.

Next, the semiconductor wafer is diced to form a semiconductor wafer. During the period from the formation of the protective film to the dicing, the protective film may be irradiated with laser light from the side of the coating layer of the composite sheet for forming a protective film, and printed on the surface of the protective film. In this case, as described above, by making the measured value of the haze from the side of the coating layer in the composite sheet for forming a protective film into a specific range as described above, the protective film can be clearly polished. Shooting prints.

In addition, the semiconductor wafer obtained by cutting or the semiconductor wafer obtained by dicing may be inspected by an infrared camera or the like from the side of the back surface (the surface on which the composite sheet for forming a protective film is attached). Its status. For example, in the case of a semiconductor wafer, it is sometimes checked for damage such as defects or cracks.

On the other hand, in the semiconductor wafer with a protective film of the present invention, the measured value of the haze on the side from the coating layer as described above is within the specific range as described above, and further, in the coating layer and the support sheet. The generation of the void portion between the back surfaces is suppressed. Therefore, when the semiconductor wafer or the semiconductor wafer is observed by the infrared camera or the like through the composite sheet for forming the protective film from the side of the coating layer, the inspection image can be obtained with high precision, so that the inspection can be performed with high precision.

Next, the semiconductor wafer is peeled off and picked up by a self-supporting sheet together with a protective film attached to the back surface thereof to obtain a semiconductor wafer with a protective film. For example, when the support sheet is formed by laminating a substrate and an adhesive layer and the adhesive layer is an energy ray-curable adhesive layer, the adhesive layer is cured by irradiating the energy ray, and the adhesive layer is cured after the curing. The agent layer picks up the semiconductor wafer together with the protective film attached to the back surface thereof, and more easily obtains the semiconductor wafer with the protective film.

For example, when the composite sheet 1 for forming a protective film shown in FIG. 1 is used, the back surface of the semiconductor wafer is attached to the film 13 for forming a protective film of the composite sheet 1 for forming a protective film, and the exposed support sheet 10 is attached. (Adhesive layer 12) is attached to a cutting jig (not shown) such as a ring frame, and the composite sheet 1 for forming a protective film is fixed to a cutting device. Next, after the protective film forming film 13 is cured to form a protective film, the protective film is subjected to laser printing, followed by dicing, and the adhesive layer 12 is attached to the above treatment by irradiating the energy ray as necessary. Protective film will be attached after curing in areas other than the part The semiconductor wafer can be picked up. When the adhesive sheet 12 is used as the energy ray-curable composite film 1 for forming a protective film, it is necessary to prevent the adhesive layer from being peeled off from the jig, and the adhesive layer 12 is not caused. The specific area is cured in such a way that it is cured. On the other hand, in the case of using the composite sheet 1 for forming a protective film, it is not necessary to separately provide a configuration for attaching the same to the jig.

On the other hand, when the composite sheet 2 for forming a protective film shown in FIG. 2 is used, the back surface of the semiconductor wafer is attached to the film 23 for forming a protective film of the composite sheet 2 for forming a protective film, and the jig is attached. The adhesive layer 16 is attached to a cutting jig (not shown) such as an annular frame, and the protective film forming composite sheet 2 is fixed to the cutting device. Then, after the protective film forming film 23 is cured to form a protective film, the protective film is subjected to laser printing, followed by dicing, and if necessary, the adhesive layer 12 is cured by irradiation of the energy ray, and the protective layer is additionally protected. The semiconductor wafer of the film can be picked up. When the adhesive sheet 12 is used as the energy ray-curable composite film 2 for forming a protective film, unlike the case of using the composite sheet 1 for forming a protective film, it is not necessary to prevent the specific region of the adhesive layer 12 from being formed. The way of curing is adjusted. On the other hand, the composite sheet 2 for forming a protective film is different from the composite sheet 1 for forming a protective film, and it is necessary to provide the adhesive layer 16 for a jig. By providing the adhesive layer 16 for a jig, a wide range of compositions can be selected for the adhesive layer 12 depending on the purpose.

Next, a method of using the composite sheet for forming a protective film in the case where the film for forming a protective film is energy ray curable is described.

In this case, the protective film forming film of the composite film for forming a protective film is attached to the back surface of the semiconductor wafer, and the protective film is formed, in the same manner as in the case where the film for forming a protective film is thermosetting. The composite sheet is fixed to the cutting device.

Next, the film for forming a protective film is cured by irradiation of an energy ray to form a protective film. When the back surface polishing tape is attached to the surface (electrode forming surface) of the semiconductor wafer, the back surface polishing tape is usually removed from the semiconductor wafer to form a protective film.

Next, the semiconductor wafer is diced to form a semiconductor wafer. During the period from the formation of the protective film to the dicing, the protective film may be irradiated with laser light from the side of the coating layer of the composite sheet for forming a protective film, and printed on the surface of the protective film. In the same manner as in the case where the film for forming a protective film is thermally curable, the protective film can be clearly subjected to laser printing in the same manner as in the case of the printing, and an infrared camera or the like can be used. The inspection is performed with high precision.

Next, the semiconductor wafer and the protective film attached to the back surface thereof are peeled off by a self-supporting sheet and picked up to obtain a semiconductor wafer with a protective film.

The method is particularly suitable for, for example, layering a substrate and an adhesive layer using a support sheet, and the aforementioned adhesive layer is a non-energy curing adhesive. The layer is used as a composite sheet for forming a protective film. In the case where the film for forming a protective film is cured by irradiation of an energy ray, the semiconductor wafer is diced, and a semiconductor wafer with a protective film is picked up, but the above-mentioned adhesive layer is non-energy curing. In the case of the property, the curing of the film for forming a protective film by irradiation of the energy ray can be performed at any stage until the semiconductor wafer is picked up.

For example, in the case of using a support sheet to laminate a substrate and an adhesive layer, and the above-mentioned adhesive layer is an energy ray-curable composite film for forming a protective film, the method described below is preferred.

In other words, the back surface of the semiconductor wafer is attached to the film for forming a protective film of the composite sheet for forming a protective film, and the composite sheet for forming a protective film is fixed to the dicing apparatus.

Next, the protective film is irradiated with laser light from the side of the coating layer of the composite sheet for forming a protective film, and is printed on the surface of the protective film, and the semiconductor wafer is diced to form a semiconductor wafer. In the same manner as in the case where the film for forming a protective film is thermally curable, the protective film can be clearly subjected to laser printing in the same manner as in the case of the printing, and an infrared camera or the like can be used. The inspection is performed with high precision.

Next, a film for forming a protective film is cured by irradiation of an energy ray to form a protective film, and the adhesive layer is cured, and the semiconductor wafer and the protective film attached to the back surface thereof are bonded together from the cured adhesive layer. Picking up, thereby obtaining a semiconductor wafer with a protective film.

On the other hand, when a long laminated film for forming a protective film is wound up, a release film is usually laminated on the exposed surface of the film for forming a protective film (the release film 15 in FIGS. 1 and 2). a composite sheet for forming a protective film. In addition, the composite sheet for forming a protective film of the present invention has any configuration (for example, any of the composite sheet for forming a protective film shown in FIG. 1 and the composite sheet 2 for forming a protective film shown in FIG. 2). In the case where the composite sheet for forming a protective film is wound into a roll shape, the layers of the coating layer, the support sheet, the film for forming a protective film, and the release film are sequentially laminated in the diameter direction of the roll. . As a result, the surface of the peeling film of one build unit (the side opposite to the side where the film for forming a protective film is provided) and the other laminated unit are laminated between the laminated units which are in contact with each other in the diameter direction of the roll. The back surface of the coating layer (the surface opposite to the side contacting the substrate) is brought into contact with each other, and is pressed, and the roll of the composite sheet for forming a protective film is stored in this state. However, since the coating layer is provided, the adhesion between the release film and the coating layer is suppressed between the laminate units. Therefore, the composite sheet for forming a protective film of the present embodiment suppresses adhesion.

The composite sheet for forming a protective film having a release film formed on the film for forming a protective film, and the peeling force of the release film measured by the following method is preferably 10 mN/50 mm or less, more preferably 7.5 mN. /50mm or less, especially preferably 5mN/50mm or less.

(Method for measuring peeling force of peeling film)

The composite sheet for forming a protective film of the present invention having a width of 50 mm and a length of 100 mm in a state in which a film is provided on the film for forming a protective film has a coating layer oriented in the same direction and a total thickness of the coating layer of 10 μm to 60 μm. In the manner of laminating a plurality of sheets, the first outermost layer is a coating layer and the second outermost layer is a laminate of a release film, and the laminate is applied with 980.665 mN in the lamination direction of the composite sheet for forming a protective film (also In the state of the force (external force) of 100 gf), the film was allowed to stand at 40 ° C for 3 days, and then the release film which was closest to the coating layer of the first outermost layer in the laminating direction was measured at a peeling speed of 300 mm/min and peeled off. The peeling force at the angle of 180° from the peeling of the adjacent coating layer (the coating layer closest to the coating layer of the first outermost layer in the stacking direction).

In addition, the composite sheet for forming a protective film formed by laminating a plurality of sheets here has the same constitution. Further, the number of sheets of the composite sheet for forming a protective film to be laminated is preferably 10 sheets. According to the peeling force of the release film, the degree of adhesion inhibition (blocking resistance) of the composite sheet for forming a protective film of the present embodiment can be confirmed.

[Examples]

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

<Manufacture of composite sheet for forming a protective film>

[Example 1]

A composite sheet for forming a protective film having the structure shown in Fig. 1 was produced. A plan view of the composite sheet for forming a protective film is shown in Fig. 3 . More specifically, it is as follows.

[Manufacture of the first laminate]

(Preparation of a composition for forming a thermosetting protective film)

The following components were blended in the following amounts (solid content), and methyl ethyl ketone was blended to obtain a protective film-forming composition (III-1) having a solid concentration of 51% by mass.

(polymer component (A))

(A)-1: an acrylic resin obtained by copolymerizing 10 parts by mass of n-butyl acrylate, 70 parts by mass of methyl acrylate, 5 parts by mass of glycidyl methacrylate, and 15 parts by mass of 2-hydroxyethyl acrylate ( The weight average molecular weight was 400,000, and the glass transition temperature was -1 ° C) of 150 parts by mass.

(thermosetting component (B))

‧Epoxy resin (B1)

(B1)-1: bisphenol A type epoxy resin ("JER828" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent: 183 g/eq to 194 g/eq, molecular weight: 370) 60 parts by mass.

(B1)-2: bisphenol A type epoxy resin ("JER1055" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent: 800 g/eq to 900 g/eq, molecular weight 1600) 10 parts by mass.

(B1)-3: 30 parts by mass of a dicyclopentadiene type epoxy resin ("Epiclon HP-7200HH" manufactured by DIC Corporation, epoxy equivalent: 274 g/eq to 286 g/eq).

‧Hot curing agent (B2)

(B2)-1: 2 parts by mass of dicyandiamide (solid dispersion-type latent curing agent, "Adeka Hardener EH-3636AS" manufactured by ADEKA Co., Ltd., active hydrogen amount 21 g/eq).

(curing accelerator (C))

(C)-1: 2 parts by mass of 2-phenyl-4,5-dihydroxymethylimidazole ("Curezol 2PHZ" manufactured by Shikoku Kasei Kogyo Co., Ltd.).

(filler (D))

(D)-1: 320 parts by mass of a cerium oxide filler ("SC2050MA" of Admatechs Co., Ltd., surface-modified with an epoxy-based compound, average particle diameter: 0.5 μm).

(coupler (E))

(E)-1: γ-glycidoxypropyltrimethoxydecane (a decane coupling agent, "KBM403" manufactured by Shin-Etsu Chemical Co., Ltd., a methoxy equivalent of 12.7 mmol/g, a molecular weight of 236.3) 0.4 parts by mass.

(colorant (I))

(I)-1: 1.2 parts by mass of carbon black (pigment, "MA600B" manufactured by Mitsubishi Chemical Corporation, average particle diameter: 28 nm).

(Formation of film for forming a protective film, production of a first layered body)

The protective film-forming composition (III-1) obtained by applying the above-mentioned peeling-treated film of the first release film ("SP-P502010*" manufactured by Lintec Co., Ltd., thickness: 50 μm) on the peeling-treated surface using a knife coater The film was dried at 120 ° C for 2 minutes to form a film for forming a protective film (thickness: 25 μm).

Then, the peeling-treated surface of the second release film ("SP-PET381031C" manufactured by Lintec Co., Ltd., thickness: 38 μm) was bonded to the surface of the film for forming a protective film on the side opposite to the surface on which the first release film was provided. In the meantime, a laminate in which a first release film, a film for forming a protective film, and a second release film are laminated in this order is obtained. Then, the laminated body is formed into a take-up roll, and the laminated body is cut into 300 mm along the width direction thereof (the width direction indicated by the symbol w1 of the protective film forming composite sheet 1 shown in Fig. 3). The size.

Then, the layered body of the cut is formed in the center portion in the width direction from the second release film side together with the second release film and the film for forming a protective film to draw a circular shape having a diameter of 220 mm in plan view. A half cut of the slit is formed. In addition, in this specification, the "top view" of a laminated body means that the laminated body is observed from top to bottom in the lamination direction. In addition, the second release film and the film for forming a protective film are removed from the laminated body by the circular portion formed by the half-cut, and the film is sequentially formed on the release-treated surface of the first release film. The first laminate having a circular protective film forming film and a second release film in a plan view is laminated. The circular protective film forming film in the first laminate is opposite to the protective film shown in FIG. A film 13 for forming a protective film having a diameter d1 of 220 mm in the composite sheet 1 was formed.

(Preparation of coating composition)

A dispersion obtained by dispersing a cerium oxide sol in 2-ethoxyethanol (ethyl cellosolve) (OSCAL1632, manufactured by Catalyst Chemical Industries, Inc., cerium oxide sol having a particle diameter of 30 nm to 50 nm, A hard coating agent composed of an urethane urethane and a polyfunctional acrylate monomer (Beamset 575CB manufactured by Arakawa Chemical Industries Co., Ltd.) having a solid content concentration of 100 mass is prepared in a solid content of 30% by mass. 100 parts by mass of the photopolymerization initiator was added to obtain a coating composition (solid content concentration: 30% by mass).

(formation of coating layer)

Then, the unevenness of the polypropylene base material (thickness: 100 μm, melting point: 140 ° C to 160 ° C) having a surface roughness Ra of 0.4 μm on the surface of the uneven surface and a surface roughness Ra of 0.02 μm on the surface opposite to the uneven surface The coating composition obtained by the above coating was applied by a bar coater, and after drying at 80 ° C for 1 minute, ultraviolet rays were irradiated with a light amount of about 230 mJ/cm ^{2 to} cure the dried coating film to form a film. Coating layer (thickness 3 μm).

(Preparation of adhesive composition)

100 parts by mass of an alkyl (meth) acrylate copolymer and an aromatic polyisocyanate compound (crosslinking agent, manufactured by Mitsui Chemicals Co., Ltd.) "Takenate D110N") 10 parts by mass (solid content), and methyl ethyl ketone was blended to obtain an adhesive composition (iii) having a solid concentration of 30% by mass.

The alkyl (meth)acrylate copolymer is a weight average molecular weight obtained by copolymerizing 40 parts by mass of n-butyl acrylate, 55 parts by mass of 2-ethylhexyl acrylate, and 5 parts by mass of 2-hydroxyethyl acrylate. 600000 acrylic resin.

(Formation of adhesive layer (support sheet), manufacture of second laminate)

A third release film (P-PET381031C manufactured by Lintec Co., Ltd.) comprising a polyethylene terephthalate film having a thickness of 38 μm formed by a release treatment of a polyfluorene-based release agent layer. On the peeling treatment surface, the adhesive composition (iii) obtained above was applied by a knife coater and dried to form an adhesive layer (thickness: 5 μm).

Next, after corona-treating the surface on the side opposite to the uneven surface of the substrate on which the coating layer is formed, the adhesive layer is bonded to the corona-treated surface to obtain a sequential laminated coating. A second layered body comprising a strip of a support sheet formed of a cloth layer, a substrate, an adhesive layer, and a third release film.

Then, the second laminated body is formed into a winding roll, and the second laminated body is oriented in the width direction (the width direction indicated by the symbol w1 of the composite sheet 1 for protective film formation shown in FIG. 3). ) Cut to a size of 300mm.

(Manufacture of composite sheet for forming a protective film)

The first laminate obtained as described above is removed from the second release film to expose the circular protective film formation film. Further, the second laminate film obtained from the above-described second laminate is removed to expose the pressure-sensitive adhesive layer. Then, the exposed surface of the film for forming a protective film is bonded to the exposed surface of the adhesive layer to obtain a coating layer, a substrate, an adhesive layer, a film for forming a protective film, and the first layer. The third laminated body corresponding to the composite sheet for forming a protective film is formed by peeling off the film.

In the third layered body obtained as described above, the entire layer of the coating layer, the substrate, and the adhesive layer was formed on the side of the coating layer so as to form a circular shape having a diameter of 270 mm in plan view. In the half cut, a slit having a diameter of 270 mm in plan view and a circle having a diameter of 220 mm formed by the film for forming a protective film is formed concentrically, and the entire coating layer, the base material, and the adhesive layer are formed.

Then, in the plan view, the 270 mm-diameter circle is drawn in the width direction of the third layered body at a position spaced apart from the outer side in the diameter direction of the circle by 20 mm (the composite sheet for forming a protective film shown in FIG. 3). In the width direction indicated by the symbol w1), a pair of arcs are formed on the side of the coating layer from the side of the coating layer, and all of the coating layer, the substrate, and the adhesive layer are cut.

The slit corresponding to the pair of circular arcs forms a curved peripheral portion of the adhesive layer indicated by reference numeral 121 in the composite sheet 1 for forming a protective film shown in Fig. 3 . And the distance between the circle of 270 mm in diameter and the aforementioned arc (20 mm) corresponds to the symbol w2 in the composite sheet 1 for forming a protective film shown in Fig. 3 .

In the longitudinal direction of the third layered body (the direction orthogonal to the width direction in the direction indicated by the symbol w1 of the composite sheet for forming a protective film shown in FIG. 3), two concentric circles are drawn. The first half of the arc of the pair is cut, and two straight lines connecting the arcs in the longitudinal direction between the adjacent portions in plan view are drawn, and the coating is performed from the side of the coating layer. The cloth layer, the substrate, and the adhesive layer all form a half cut of the slit. The slit corresponding to the two straight lines forms a planar peripheral portion of the adhesive layer indicated by reference numeral 122 in the composite sheet 1 for forming a protective film shown in Fig. 3 .

Then, a coating layer, a substrate, and an adhesive layer which are sandwiched between a circle having a diameter of 270 mm and a pair of arcs in a plan view, and a line connecting the arcs to each other in a straight line The composite sheet for forming a protective film shown in Figs. 1 and 3 was obtained by removal. The circular adhesive layer (support sheet) in the composite sheet for forming a protective film corresponds to a circular adhesive layer 12 (support sheet 10) having a diameter d2 of 270 mm in Fig. 3 . Further, the first release film in the composite sheet for forming a protective film corresponds to the release film 15 in Fig. 3 .

[Embodiment 2]

As shown in Table 1, a composite sheet for forming a protective film was obtained by the same method as in Example 1 except that the surface roughness Ra of the uneven surface was not 0.4 μm and the substrate was 1 μm.

[Example 3]

As shown in Table 1, the same method as in Example 1 was used except that the surface roughness Ra of the uneven surface was not 0.4 μm and was 1 μm, and the thickness of the coating layer was changed from 3 μm to 1 μm. A composite sheet for forming a protective film was obtained.

[Example 4]

As shown in Table 1, a composite sheet for forming a protective film was obtained by the same method as in Example 1 except that the thickness of the coating layer was changed from 3 μm to 1 μm.

[Example 5]

As shown in Table 1, the same method as in Example 1 was used except that the surface roughness Ra of the uneven surface was not 0.4 μm and was 1 μm, and the thickness of the coating layer was changed from 3 μm to 6 μm. A composite sheet for forming a protective film was obtained.

[Embodiment 6]

As shown in Table 1, the surface roughness Ra of the uneven surface was not 0.4 μm and was 3 μm, and the thickness of the coating layer was changed from 3 μm to 3 μm. A composite sheet for forming a protective film was obtained by the same method as in Example 1 except that the film was obtained in the same manner as in Example 1.

[Comparative Example 1]

As shown in Table 1, a protective film was formed by the same method as in Example 1 except that the surface roughness Ra of the uneven surface was not 0.4 μm and the substrate was 1 μm, and the coating layer was not formed. Composite sheet.

[Comparative Example 2]

As shown in Table 1, the base material was placed so that the uneven surface faced the opposite side, that is, the side (inside) of the adhesive layer, and the coating layer was not formed (that is, the conventional structure shown in Fig. 5) A composite sheet for forming a protective film was obtained by the same method as in Example 1 except the above.

[Comparative Example 3]

As shown in Table 1, the base material having the surface roughness Ra of the uneven surface is not 0.4 μm and is 1 μm, and the base material is disposed such that the uneven surface faces the opposite side, that is, the side (inside) of the adhesive layer. A composite sheet for forming a protective film was obtained by the same method as in Example 1 except that the coating layer was formed (that is, the conventional configuration shown in Fig. 5).

[Comparative Example 4]

Using the same amount of spherical cerium oxide surface-modified with an epoxy group as a solid component (Admatechs Co., Ltd.) A coating composition was prepared in the same manner as in Example 1 except that "SC2050MA" and an average particle diameter of 0.5 μm were used instead of the dispersion obtained by dispersing the cerium oxide sol in 2-ethoxyethanol. .

Further, a composite sheet for forming a protective film was obtained by the same method as in Example 1 except that the coating composition was used.

With respect to the obtained composite sheet for forming a protective film, the surface roughness Ra of the outermost surface of the substrate side was 0.8 μm as shown in Table 1.

<Evaluation of composite sheet for forming a protective film>

[Laser printability]

In the composite sheet for forming a protective film of each of the examples and the comparative examples obtained above, the first release film was removed, and an adhesive layer ("RAD-2700F/12" manufactured by Lintec Co., Ltd.) was attached, and the adhesive layer was attached thereto. A film made of a stainless steel was attached to the back surface of a silicon wafer (outer diameter 8 Å, thickness 100 μm) heated to 70 ° C.

Then, the film for forming a protective film was heat-treated at 130 ° C for 2 hours to thermally cure the film for forming a protective film to form a protective film.

Then, using a printing device ("VK9700" manufactured by KEYENCE Co., Ltd.), the protective film was irradiated with laser light having a wavelength of 532 nm from the substrate side under the conditions of output of 0.6 W, frequency of 40 kHz, and scanning speed of 100 mm/sec. The two patterns (pattern 1, pattern 2) are laser printed on the protective film.

(pattern)

Pattern 1: The character size is 0.4 mm × 0.5 mm, the character interval is 0.3 mm, and the number of characters is 20.

Pattern 2: The character size is 0.2 mm × 0.5 mm, the character interval is 0.3 mm, and the number of characters is 20.

Next, the visual form (laser printability) from the substrate side was evaluated based on the following basis for the character formed on the protective film by the above-described laser printing. The results are shown in Table 1.

(evaluation basis)

A: All the characters of patterns 1 and 2 are clear, and the characters of patterns 1 and 2 can be read without problems.

B: At least a part of the characters in the pattern 2 are not clear, but all the characters in the pattern 1 are clear, and the characters of the pattern 1 can be read without any problem.

C: At least some of the characters in patterns 1 and 2 are not clear.

[Adhesion resistance (1)]

The composite sheet for forming a protective film of each of the examples and the comparative examples obtained above was wound up to a length of 10 m to an ABS (Acrylonitrile-Butadiene-Styrene; acrylonitrile-butadiene-styrene) resin having a diameter of 3 Å. The core was placed in this state and allowed to stand at room temperature for 3 days.

Next, in the composite sheet for forming a protective film of Examples 1 to 5, 10 layers of the coating layer, the substrate, the adhesive layer, the film for forming a protective film, and the first release film were sequentially laminated. The composite sheet for protective film formation of Comparative Examples 1 to 3 was extracted, since there was no coating. In the case of the layer, the 10 layers of the substrate, the adhesive layer, the film for forming a protective film, and the first release film are sequentially taken out, and the protective film is contacted with each other at the time of winding according to the following basis. The degree of attachment of the contact portions of the formed composite sheet with or without attachment to each other was evaluated. The results are shown in Table 1.

(evaluation basis)

A: The attachment of the aforementioned contact portions to each other was not observed at all.

B: When the contact portions are slightly attached to each other, the composite sheet for forming a protective film can be taken out without any problem.

C: The contact portions are completely attached to each other in a part, and when the composite sheet for forming a protective film is taken out, the first release film is peeled off from the adhesive layer.

[blocking resistance (2)]

The composite sheet for forming a protective film of each of the examples and the comparative examples obtained above was cut into a belt having a width of 50 mm and a length of 100 mm. Further, the length direction of the tape is made to coincide with the application direction of the adhesive composition at the time of cutting.

Ten strips thus obtained were prepared, and these strips were laminated to prepare test pieces. At this time, in the case of 1 to 5, the belts were laminated with the coating layer facing upward. Further, in the case of Comparative Example 1 to Comparative Example 3, since the coating layer was not present, the tape was laminated with the substrate facing upward. Next, the test piece was sandwiched between two glass plates (width: 75 mm, length: 15 mm, thickness: 5 mm), and the laminate of the glass plate and the test piece was carried as a lowermost layer with a glass plate as a lower layer. The test piece was placed under a predetermined position, and a weight was placed on the other uppermost glass plate to pressurize the test piece. The force applied to the test piece in the lamination direction of the belt at this time was 980.665 mN (i.e., 100 gf). In this state, the laminate of the glass plate and the test piece was stored in a damp heat promoter (manufactured by ESPEC Co., Ltd.) at 40 ° C for 3 days, and the test piece was subjected to a heat and pressure promotion test.

Then, the test piece is taken out from the moist heat promoter, and the first release film (the first release film in contact with the lowermost glass plate) of the lowermost layer and the film for forming a protective film adjacent thereto are removed, and the exposed adhesive layer is exposed. By adhering to the support plate via the double-sided adhesive tape, the test piece after the heating and pressurization promotion test is removed from the lowermost first release film and the film for forming a protective film adjacent thereto. The aforementioned support plate.

Next, in the case of the first embodiment to the fifth embodiment, the laminate of the coating layer, the substrate, the adhesive layer, and the film for forming a protective film which are the furthest from the support plate among the above-mentioned holders is removed. Using the tensile tester, the exposed first release film was peeled off from the adjacent coating layer under the conditions of a peeling speed of 300 mm/min and a peeling angle of 180°, and the peeling force at this time was measured. In the case of Comparative Example 1 to Comparative Example 3, the laminate of the substrate, the adhesive layer, and the film for forming a protective film which are the furthest from the support plate among the above-mentioned holders is removed, and a tensile tester is used. The exposed first peeling film was peeled off from the adjacent base material under the conditions of a peeling speed of 300 mm/min and a peeling angle of 180°, and the peeling force at this time was measured. Will be like this The measured value of the peeling force of the obtained first release film is an index of the blocking resistance of the composite sheet for forming a protective film.

Further, when the peeling force of the first release film to be measured is sufficiently small, the first release film (the lowermost layer of the glass plate) as described above and the lowermost layer are removed from the test piece taken out from the moist heat promoter. When the film for forming a protective film is adjacent to the first release film to be contacted, the first release film to be subjected to the measurement of the peeling force may be first applied from the layer adjacent thereto (in the case of Embodiments 1 to 5) The cloth layer was peeled off in the case of Comparative Example 1 to Comparative Example 3 as a substrate. In this case, after removing the first release film of the lowermost layer from the test piece taken out from the moist heat promoter, the film for forming a protective film is not removed by removing the film for forming a protective film adjacent thereto. The surface adhesive tape is bonded to the support plate, and the first release film from which the lowermost layer is removed from the test piece is fixed to the support plate, and the first release is measured in the same manner as described above. Peeling force of the film.

The results are shown in Table 1.

[Surface roughness Ra of the outermost surface of the substrate side]

In the composite sheet for forming a protective film of each of the examples and the comparative examples obtained above, a contact surface roughness meter ("SURFTEST SV-3000" manufactured by Mitutoyo Co., Ltd.) was used, and the cutoff value λc was set to 0.8 mm, and evaluation was performed. The length Ln was set to 4 mm, and the surface roughness Ra of the outermost surface of the substrate side, that is, the surface on the side opposite to the substrate side in the coating layer was measured in accordance with JIS B0601:2001. The results are shown in Table 1. In Table 1, the composite sheet for forming a protective film of Comparative Example 1 to Comparative Example 3 was used as the outermost surface of the substrate side. The surface roughness Ra describes the surface roughness Ra of the surface on the side opposite to the side of the adhesive layer in the above-mentioned base material.

[Gloss of the surface of the coating layer]

With respect to the composite sheet for forming a protective film of each of the examples and the comparative examples obtained above, a gloss meter (gloss meter "VG 2000" manufactured by Nippon Denshoku Co., Ltd.) was used, and a base layer from the coating layer was used in accordance with JIS K 7105. The 20° specular gloss of the surface of the coating layer was measured on the opposite side of the material side, and the measured value was taken as the glossiness of the surface of the coating layer. The results are shown in Table 1.

[Measurement value of haze from the side of the coating layer]

The composite sheet for forming a protective film of each of the examples and the comparative examples obtained above was measured from the side of the coating layer in accordance with JIS K 7136 using a haze meter ("NDH-2000" manufactured by Nippon Denshoku Industries Co., Ltd.). Haze. The results are shown in Table 1.

The composite sheet for forming a protective film of Examples 1 to 6 has a coating layer on the outermost layer on the substrate side, and the measurement value of the haze on the side of the self-coating layer is small, and the laser printing property and Good adhesion resistance.

In particular, the composite printing sheets for forming protective films of the first embodiment, the second embodiment, the fourth embodiment, and the fifth embodiment are superior in laser printing performance to the composite film for forming a protective film of the third embodiment and the sixth embodiment, and the reason is presumed. In the composite sheets for forming a protective film of Example 1, Example 2, Example 4, and Example 5, the haze is further small and is more suitable.

Further, the composite sheets for forming a protective film of Examples 1 to 4 have better adhesion resistance than the composite sheets for forming a protective film of Examples 5 and 6, and it is presumed that the reason is that Examples 1 to 4 The thickness of the coating layer of the composite sheet for forming a protective film is thinner.

Further, in the composite sheet for forming a protective film of Examples 1 to 6, no void portion was observed between the substrate and the adhesive layer.

On the other hand, in the same manner as in the case shown in FIG. 4, the composite sheet for forming a protective film of Comparative Example 1 has a surface (back surface) on the opposite side to the surface (surface) on the side where the pressure-sensitive adhesive layer is provided. The uneven surface does not have a coating layer, and although excellent in blocking resistance, the laser printing property is poor.

In the composite sheet for forming a protective film of Comparative Example 2, as in the case shown in Fig. 5, the surface (back surface) on the side opposite to the surface (surface) on the side where the adhesive layer is provided is a smooth surface and is not provided. Although the coating layer has good laser printability, it has poor adhesion resistance. The composite sheet for forming a protective film of Comparative Example 3 although Although it has the same structure as the composite sheet for forming a protective film of Comparative Example 2, it has poor adhesion resistance and poor laser printability. The reason for this is that the surface (surface) on the side where the pressure-sensitive adhesive layer is provided on the substrate is an uneven surface, and the surface roughness Ra thereof is larger than that of the composite film for forming a protective film of Comparative Example 2. According to the comparative example 3, since the surface roughness Ra of the uneven surface is large, the shape of the uneven surface is also reflected on the surface of the protective film, and the degree of unevenness on the surface of the protective film becomes larger than that of the comparative example 2, resulting in The diffuse reflection of light becomes larger, and the laser printability is worse. Further, it is estimated that the composite sheet for forming a protective film of Comparative Examples 2 and 3 has a void portion between the uneven surface of the substrate and the adhesive layer, but the surface roughness Ra of the uneven surface of Comparative Example 3 is larger than that of Comparative Example 2. Therefore, the void portion becomes larger, and therefore the diffuse reflection of light of Comparative Example 3 is larger than that of Comparative Example 2, and the laser printability is worse.

In the composite sheet for forming a protective film of Comparative Example 4, the surface (back surface) on the side opposite to the surface (surface) on the side where the pressure-sensitive adhesive layer is provided is the unevenness in the same manner as the composite sheet for forming a protective film of Example 1. The surface also has a coating layer, and although excellent in blocking resistance, the laser printing property is poor. The reason for this is that the measured value of the haze from the side of the coating layer in the composite sheet for forming a protective film of Comparative Example 4 is large.

(industry availability)

The present invention can be applied to the manufacture of a semiconductor wafer or the like which is protected by a protective film on the back surface.

1‧‧‧Composite film for protective film formation

10‧‧‧Support film

10a‧‧‧Surface of the support piece

10b‧‧‧Back of the support piece

11‧‧‧Substrate

11a‧‧‧ Surface of the substrate

11b‧‧‧The back of the substrate

12‧‧‧Adhesive layer

12a‧‧‧ Surface of the adhesive layer

13‧‧‧film for protective film formation

13a‧‧‧Surface of film for protective film formation

14‧‧‧ Coating layer

14a‧‧‧Surface of the coating layer

14b‧‧‧Back of the coating layer

15‧‧‧Release film

15a‧‧‧ peeling film surface

Claims (5)

A composite sheet for forming a protective film, comprising a film for forming a protective film on one surface of the support sheet, and a coating layer on a surface of the support sheet opposite to the side including the film for forming a protective film; The measured value of the haze from the side of the coating layer in the composite sheet for forming a protective film was 47% or less. The composite sheet for forming a protective film according to the first aspect of the invention, wherein the protective film forming composite sheet further comprising a release film on the film for forming a protective film is used, and the release film is measured by the following method. The peeling force is 10 mN/50 mm or less, and the peeling force of the peeling film is measured by the above-mentioned coating film for forming a protective film having a peeling film and having a width of 50 mm and a length of 100 mm. The laminated body is formed by laminating a plurality of sheets in such a manner that the layers are oriented in the same direction and the total thickness of the coating layer is from 10 μm to 60 μm, and the first outermost layer is a coating layer and the second outermost layer is a release film. A release film which is closest to the coating layer of the first outermost layer in the laminating direction after the surface of the composite sheet for forming a protective film is applied with a force of 980.665 mN at 40 ° C for 3 days. Peeling was performed from the adjacent coating layer under the conditions of a peeling speed of 300 mm/min and a peeling angle of 180°, and the peeling force at this time was measured. The composite sheet for forming a protective film according to claim 1, wherein the support sheet is formed by laminating a substrate and an adhesive; The composite sheet for forming a protective film is formed by sequentially laminating the coating layer, the substrate, the adhesive layer, and the film for forming a protective film. The composite sheet for forming a protective film according to claim 3, wherein the adhesive layer is an energy ray-curable or non-energy-curable adhesive layer. The composite sheet for forming a protective film according to any one of claims 1 to 4, wherein the film for forming a protective film is a film for forming a protective film which is thermosetting or energy ray curable.