TW201732002A - Composite film for forming a protective film - Google Patents

Abstract

The composite sheet for forming a protective film of the present invention comprises a support sheet, and a film for forming a protective film is provided on one surface of the support sheet, and is on a surface opposite to the side of the support sheet having the film for forming a protective film. A coating layer is provided; a surface roughness Ra of a surface on the opposite side to the side in contact with the support sheet in the coating layer is smaller than a surface roughness Ra of a surface of the support sheet on the side having the coating layer.

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. 2016-042689, filed on Jan.

In recent years, the industry has manufactured semiconductor devices using a mounting method called a so-called face down method. In the flip chip method, a semiconductor wafer having electrodes such as bumps on a circuit surface is used, and the electrodes are bonded to the substrate. Therefore, sometimes the back surface of the wafer opposite to the circuit surface is exposed.

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

When such a protective film is formed, it is used to form a protective film on the support sheet. A composite sheet for forming a protective film of a film. As the support sheet, for example, a resin substrate or a laminate structure such as a substrate or an adhesive layer may be used, and the surface layer of the film for forming a protective film or the adhesive layer of the substrate may be subjected to surface treatment. In the composite sheet for forming a protective film, the film for forming a protective film has a function of forming a protective film, and the support sheet can function as a dicing sheet, and the film for forming a protective film is integrally formed with the dicing sheet. A composite sheet for forming a protective film.

Generally, the one or both sides of the aforementioned substrate before the processing for supporting the sheet have a concavo-convex shape. The reason is that if such a concavo-convex shape is not obtained, when the substrate is wound into a roll, the contact faces of the substrates adhere to each other to cause blocking, which is difficult to use. When at least one of the contact faces of the substrates has an uneven shape, the area of the contact faces becomes small, and thus the adhesion is suppressed.

The conventional composite sheet for forming a protective film using such a substrate having an uneven surface has a configuration as shown in Fig. 4 . Fig. 4 is a cross-sectional view showing an example of a conventional composite sheet for forming a protective film. In the drawings used in the following description, for example, in order to facilitate the understanding of the characteristics of the composite sheet for forming a protective film, it is convenient to show a part which is a main part, and is not limited to the size of each constituent element. The ratio and the like are the same as the actual ones.

The conventional protective film forming composite sheet 9 shown here is a support sheet. 90 is provided with a film 13 for forming a protective film, and the support sheet 90 is composed of a laminated structure of the substrate 91 and the adhesive layer 12, and a film 13 for forming a protective film is provided on the adhesive layer 12. The film 13 for forming a protective film is cured to form a protective film. The protective film forming composite sheet 9 further includes a release film 15 on the protective film forming film 13 and removes the release film 15 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 of the support sheet 90 opposite to the surface (surface) 90a including the film for forming a protective film, that is, the adhesive layer is provided in the substrate 91. The surface (back surface) 91b on the opposite side (surface) 91a of 12 is an uneven surface. The composite sheet 9 for forming a protective film has the back surface 91b of the substrate 91 as an uneven surface as described above, and the adhesion is suppressed when the roll is wound into a roll. In other words, the adhesion of the laminated protective film forming composite sheets 9 to each other is suppressed, and more specifically, the adhesion of the back surface 91b of the substrate 91 to the exposed surface (surface) 15a of the release film 15 is suppressed.

On the other hand, in the composite sheet for forming a protective film, the surface of the protective sheet formed of the protective film forming film may be printed by irradiating laser light (hereinafter, referred to as "laser printing"). ). In the case of laser printing, the support sheet is irradiated on the opposite side to the side on which the protective film is formed. In this case, for example, in the case of the composite sheet 9 for forming a protective film, the protective film is irradiated with the laser light from the back surface 91b side of the substrate 91 through the support sheet 90. However, since the back surface 91b of the substrate 91 is an uneven surface, The diffuse surface will be diffusely reflected, and there is a problem that the laser printing is not clear.

As a composite sheet for forming a protective film which can prevent such a light from being diffused and reflected, a composite sheet 8 for forming a protective film having a structure as shown in Fig. 5 is known (for example, see Patent Document 1). Fig. 5 is a cross-sectional view showing another example of a conventional composite sheet for forming a protective film.

In the conventional composite sheet for forming a protective film 8 as shown here, a protective film forming film 13 is provided 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 composed of a base material 81 and an adhesive layer 12. The laminated structure is configured to include a film 13 for forming a protective film on the adhesive layer 12. However, 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 having the adhesive layer 12 in the base material 81 is an uneven surface, and the surface (back surface) 81b of the base material 81 opposite to the surface 81a is formed. Smooth surface. The base material 81, the protective film formation film 13, and the release film 15 in the support sheet 80 are the same as the base material 91, the protective film formation 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, that is, the surface (back surface) 80b of the support sheet 80 opposite to the surface (surface) 80a having the adhesive layer 12 is smoothed. When the composite sheet 8 for forming a protective film is wound into 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. When the adhesion occurs, wrinkles are formed in the composite sheet 8 for forming a protective film, and when the composite sheet 8 for forming a protective film is wound up from a roll, the release film 15 is formed from a protective film. The film 13 is peeled off. Further, in order to eliminate the uneven shape, the adhesive layer 12 must have a sufficient thickness on the surface 81a of the substrate 81. When the thickness of the adhesive layer 12 is insufficient, the surface (back surface) 13b on the side of the support sheet 80 of the film 13 for forming a protective film is formed to have an uneven shape, and the protective film is formed. The laser printed on the side of the support sheet on which the protective film formed by the film 13 is formed is unclear.

As described above, in the past, there has been no composite film for forming a protective film which can achieve both laser adhesion suppression and adhesion to a protective film.

[Previous Technical Literature] [Patent Literature]

Patent Document 1: Japanese Patent No. 5432853.

An object of the present invention is to provide a composite sheet for forming a protective film for forming a protective film on the back surface of a semiconductor wafer, and the composite sheet for forming a protective film can suppress adhesion, and can perform laser printing on the protective film clearly.

The present invention provides a composite sheet for forming a protective film, comprising a support sheet, and a film for forming a protective film on one surface of the support sheet, and a side opposite to a side of the support sheet having the film for forming a protective film. a coating on the surface; in the foregoing coating, in contact with the aforementioned support sheet The surface roughness Ra of the surface on the opposite side is smaller than the surface roughness Ra of the surface of the support sheet on the side having the coating.

In the composite sheet for forming a protective film of the present invention, the composite sheet for forming a protective film further comprising a release film on the film for forming a protective film is used, and the peeling force of the release film measured by the following method may be 10 mN/50 mm. the following.

(Method for measuring peeling force of peeling film)

In the film for forming a protective film, the composite film for forming a protective film having a width of the peeling film of 50 mm and a length of 100 mm is provided, and the plurality of sheets are stacked such that the entire coating layer faces in the same direction and the total thickness of the coating layer is 10 μm to 60 μm. In this way, the outermost layer of one of the coating layers is formed, and the other outermost layer is a laminate of the release film, and the laminated body is applied with a force of 980.665 mN in the lamination direction of the composite sheet for forming a protective film. After standing at 40 ° C for 3 days, the release film closest to the coating of the outermost layer in the laminating direction was peeled off from the adjacent coating at a peeling speed of 300 mm/min and a peeling angle of 180°. The peeling force at this time.

In the composite sheet for forming a protective film of the present invention, the support sheet may be formed by laminating a substrate and an adhesive, and the composite sheet for forming a protective film may be formed of the coating layer, the substrate, the adhesive layer and the protective film. The film is formed by sequential lamination.

In the composite sheet for forming a protective film of the present invention, the pressure-sensitive adhesive layer may be an energy ray-curable layer or a non-energetic layer.

In the composite sheet for forming a protective film of the present invention, the film for forming a protective film may be a layer of thermosetting or an energy ray-curable layer.

The composite sheet for forming a protective film of the present invention is used for forming a protective film on the back surface of a semiconductor wafer, and by using the composite sheet for forming a protective film, adhesion of the composite sheet for forming a protective film can be suppressed, and the protective film can be clearly defined. Laser printing is carried out.

1, 2, 8, 9 ‧ ‧ composite film for protective film formation

10, 80, 90‧‧‧ Support tablets

10a, 80a, 90a‧‧‧ support sheet surface

10b, 80b, 90b‧‧‧ back of the support piece

11, 81, 91‧‧‧ substrate

11a, 81a, 91a‧‧‧ surface of the substrate

11b, 81b, 91b‧‧‧ 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

13b‧‧‧Back of the film for protective film formation

14‧‧‧ Coating

14a‧‧‧Coated surface

14b‧‧‧The back of the coating

15‧‧‧Release film

15a‧‧‧ peeling film surface

16‧‧‧Layer layer for fixtures

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

121‧‧‧The curved peripheral portion of the adhesive layer

122‧‧‧The planar peripheral portion of the adhesive layer

d ₁ , d ₂ ‧‧‧ diameter

w ₁ , w ₂ ‧‧‧width

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

Fig. 2 is a cross-sectional view showing another embodiment of the composite sheet for forming a protective film 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 showing an example of a conventional composite sheet for forming a protective film.

Fig. 5 is a cross-sectional view 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 invention comprises a support sheet, and the aforementioned support a film for forming a protective film is provided on the surface of one of the holding sheets, and a coating layer is provided on a surface of the support sheet opposite to the side including the film for forming a protective film; and the support sheet in the coating layer The surface roughness Ra of the surface on the opposite side of the contact side is smaller than the surface roughness Ra of the surface of the support sheet on the side having the coating layer.

In the composite sheet for forming a protective film, the surface roughness Ra of the surface on the side opposite to the side in contact with the support sheet in the coating layer is smaller than the surface roughness of the surface on the side of the support sheet having the coating layer. Ra. That is, the surface on the opposite side to the side in contact with the support sheet in the coating layer is a smooth surface or a surface on which the degree of unevenness is suppressed. Therefore, when the laser light is irradiated, it is possible to suppress the diffuse reflection of the laser light on the aforementioned surface having a small surface roughness Ra of the coating layer. Therefore, when the protective film which cured the film for forming a protective film is irradiated with the laser light from the coating side through the support sheet, the protective film can be clearly subjected to laser printing.

Further, the coating layer in the above-mentioned composite sheet for forming a protective film is apt to slide moderately with respect to the contact with the coating layer, and has antistatic properties. Therefore, when the composite sheet for forming a protective film is taken up into a roll, adhesion of the laminated protective film forming composite sheets, that is, adhesion, can be suppressed.

In the above-mentioned composite sheet for forming a protective film, the film for forming a protective film is cured to a protective film by heating or irradiating an energy ray, and the laminated structure of the support sheet and the protective film can be maintained. ,then It is called "composite sheet for forming a protective film". Further, in the case of the composite sheet for forming a protective film, in the case where the support sheet is a laminated structure of a substrate and an adhesive layer, the sheet obtained by curing the adhesive layer is also required to maintain the substrate and the adhesive layer. The laminated structure of the cured film and the film for forming a protective film or the protective film is referred to as a "composite sheet for forming a protective film".

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

The composite sheet 1 for forming a protective film shown here is provided with a support sheet 10, and a film 13 for forming a protective film is provided on one surface 10a of the support sheet 10, and is provided on the other surface (back surface) 10b of the support sheet 10. Coating 14. Further, the support sheet 10 is formed by laminating the base material 11 and the adhesive layer 12, and the adhesive layer 12 is provided on one surface 11a of the base material 11, and is provided on the other surface (back surface) 11b of the base material 11. The coating 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 protective film forming film 13 is laminated on a part of the surface 12a of the adhesive layer 12. Further, on the surface 12a of the adhesive layer 12, the exposed surface of the protective film forming film 13 and the surface 13a (in other words, the upper surface and the side surface) of the protective film forming film 13 are peeled off. Release film 15.

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 protective film formation or the vicinity of the film 13 for protective film formation 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 surface (back surface) 10b of the support sheet 10 opposite to the surface (surface) 10a including the film for forming a protective film 10 is an uneven surface, in other words, the substrate 11 is adhered. The surface (back surface) 11b on the surface (surface) 11a of the agent layer 12 is an uneven surface. Further, the coating layer 14 is provided to cover the uneven surface. The surface roughness Ra of the surface (back surface) 14b of the coating layer 14 which is opposite to the surface (surface) 14a which is in contact with the support sheet 10 (substrate 11) is smaller than the aforementioned back surface 10b of the support sheet 10 (in other words, the substrate) The surface roughness Ra of the aforementioned back surface 11b) of 11. 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, as described above, the surface roughness Ra of the aforementioned back surface 14b of the coating layer 14 is small, whereby the diffuse reflection of the laser light on the coating layer 14 can be suppressed. Therefore, the protective film can be clearly subjected to laser printing.

In the present specification, the term "surface roughness Ra" means a so-called arithmetic mean roughness defined in JIS B0601:2001 unless otherwise specified.

In addition, when the composite sheet 1 for forming a protective film is provided with the coating layer 14, even when the roll is wound into a roll, it is possible to suppress adhesion of the laminated protective film forming composite sheets 1, that is, adhesion. More specifically, adhesion of the aforementioned back surface 11b of the substrate 11 to the exposed surface (surface) 15a of the release film 15 can be suppressed.

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. However, as will be described later, it is easier to suppress the occurrence of voids between the substrate 11 and the adhesive layer 12, and it is preferable that the composite sheet 1 for forming a protective film has a preferable property. The surface 11a is a smooth surface.

When the composite sheet 1 for protective film formation shown in FIG. 1 is used, the release film 15 is removed, and the back surface of the semiconductor wafer (not shown) is attached to the surface 13a of the film 13 for protective film formation. In addition, the exposed surface of the film 12 for the protective film formation in the surface 12a of the adhesive layer 12 is attached to a jig such as a ring frame.

Fig. 2 is a cross-sectional view showing another embodiment of the composite sheet for forming a protective film of the present invention. In FIG. 2, the same components as those in FIG. 1 are denoted by the same reference numerals as those in FIG. 1, and detailed description of the components will be omitted. The same is true in the figures of Fig. 2 and later.

Here, in the composite sheet 2 for forming a protective film, in the adhesive layer The protective film forming film 23 is formed over the entire area of the surface 12a of the surface 12a, and the adhesive layer 16 for the jig is laminated on a part of the surface 23a of the protective film forming film 23. In the composite sheet 2 for forming a protective film, the exposed surface of the adhesive layer 16 for the fixture and the surface 16a of the adhesive layer 16 for the jig are not laminated on the surface 23a of the film 23 for forming a protective film (in other words, A release film 15 is laminated on the upper surface and the side surface. In addition to these points, the composite sheet 2 for forming a protective film is the same as the composite sheet 1 for forming a protective film shown in Fig. 1 .

Further, a void portion may be present between the peeling film 15 and the surface 23a of the protective film forming film 23 or the surface 16a of the adhesive adhesive layer 16. For example, the side surface of the adhesive agent layer 16 and the vicinity of the adhesive layer 16 in the surface 23a of the protective film forming film 23 are 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 back surface 10b of the support sheet 10 (the back surface 11b of the base material 11) is an uneven surface, and the coating layer 14 covers the uneven surface. And set. Therefore, the surface roughness Ra of the aforementioned back surface 14b of the coating layer 14 is smaller than the surface roughness Ra of the aforementioned back surface 10b of the support sheet 10. Therefore, the protective film formed of the film 23 for protective film formation can be clearly subjected to laser printing.

In addition, when the composite sheet 2 for forming a protective film is provided with the coating layer 14, it is possible to suppress adhesion of the laminated composite sheet 2 for forming a protective film, that is, adhesion, even when it is wound into a roll.

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

The composite sheet for forming a protective film of the present invention is not limited to the composite sheet for forming a protective film shown in FIGS. 1 to 2, and the protection shown in FIGS. 1 to 2 can be also prevented without departing from the effects of the present invention. A part of the composite sheet for film formation is changed or deleted, or a composite sheet for forming a protective film described above is further added to the other structure.

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

○Support film

The support sheet is not particularly limited as long as it can provide the film for forming a protective film. Examples of the support sheet include a release sheet for preventing dust from adhering to the surface of the film for forming a protective film, and a surface for protecting the surface of the film for forming a protective film in a dicing step or the like, and functioning as a dicing sheet. Support piece.

As a preferred support sheet, a support sheet made of only a base material and a support sheet obtained by laminating a base material and an adhesive, which are generally used in the field of processing sheets for semiconductor wafers, may be mentioned.

The support sheet may be composed of one layer (single layer) or multiple 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, and 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 the plural layers is not particularly limited. Here, the plural layers are different from each other, meaning 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 the protective film can be more clearly laser-printed, and the flexible film can be provided with sufficient flexibility for adhesion to the semiconductor wafer. In a good aspect, it is preferably from 10 μm to 500 μm, more preferably from 20 μm to 350 μm, still more preferably from 30 μm to 200 μm, and for example, may be any of 40 μm to 175 μm and 50 μm to 150 μm.

Here, the term "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 substrate and an adhesive layer are laminated, meaning the thickness of the substrate and the adhesive. The total value of the thickness of the layer.

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

‧Substrate

The material of the substrate is preferably various resins.

Specific examples of the resin include polyethylene (LDPE; Low-density Polyethylene, Linear Low-density Polyethylene, High Density Polyethylene, HDPE; High). -density Polyethylene, etc.)), polypropylene, ethylene-propylene copolymer, polybutene, polybutadiene, polymethylpentene, polyvinyl chloride, vinyl chloride copolymer, polyethylene terephthalate, poly Ethylene naphthalate, polybutylene terephthalate, polyurethane, polyacrylamide, polyimine, ethylene-vinyl acetate copolymer, ionic polymer resin, ethylene - (meth)acrylic acid copolymer, ethylene-(meth)acrylate copolymer, polystyrene, polycarbonate, fluororesin, and hydride, modification, cross-linking or copolymerization of any of these resins Things and so on.

Further, in the present specification, the concept of "(meth)acrylic acid" includes both "acrylic acid" and "methacrylic acid".

In the case where the support sheet is formed by 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, for example, 30 μm to 175 μm. Any of 40 μm to 150 μm and 50 μm to 125 μm. When the thickness of the substrate is in such a range, 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 may be composed of 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 mutually The same can be different. Here, the phrase "the plural layers may be the same or different from each other" means the same meaning as in the case of the above-mentioned support sheet.

In the case where the substrate is composed of a plurality of layers, the total thickness of each layer may be the thickness of the above preferred substrate.

The surface roughness Ra of the surface (surface) having the adhesive layer in the substrate 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 the surface roughness Ra of the surface of the substrate being 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 the molding conditions of the substrate, the surface treatment conditions of the substrate, and the like.

Further, as a method of singulating a semiconductor wafer into a semiconductor wafer by dicing, for example, a method of dicing using a blade cut into a semiconductor wafer and cutting a semiconductor wafer by laser irradiation may be cited. Shot cutting, or water cutting by cutting a semiconductor wafer by blowing water containing an abrasive.

On the other hand, as a method of singulating a semiconductor wafer into a semiconductor wafer, in addition to the method of using the dicing, a method of illuminating the infrared region by focusing on a focus set inside the semiconductor wafer may be mentioned. The laser beam is formed into a modified layer inside the semiconductor wafer, and then a force is applied to the semiconductor wafer to divide and singulate the semiconductor wafer at a portion where the modified layer is formed.

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 preferably forms a modified layer and a semiconductor crystal inside the semiconductor wafer. Used when the circle is singulated.

On the other hand, the surface roughness Ra of the surface (back surface) on the opposite side to the surface (surface) having the adhesive layer in the substrate, in other words, the surface (surface) of the support sheet and the film for forming a protective film is The surface roughness Ra of the face (back surface) on the opposite side is preferably from 0.001 μm to 4 μm, more preferably from 0.005 μm to 3.7 μm, still more preferably from 0.01 μm to 3.4 μm, still more preferably from 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 opposite side to the side in contact with the support sheet in the coating layer can be more easily reduced, thereby making it easier to The protective film is clearly laser printed.

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

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

Further, the base material using the resin as a constituent material may be formed by extrusion of a thermoplastic resin, or may be stretched, and may be formed by thinning and hardening of a curable resin by a known means.

Alternatively, the substrate can be colored or printed.

Excellent in heat resistance and extended by moderate flexibility The substrate preferably contains polypropylene in terms of suitability and good pickability.

The base material containing polypropylene may be, for example, a single layer or a plurality of layers made of polypropylene, or a plurality of layers (two or more layers) in which a polypropylene layer and a resin other than polypropylene are laminated. Substrate.

When the film for forming a protective film is thermosetting, the substrate has heat resistance, and deterioration of the substrate due to heat can be suppressed, and it is possible to effectively suppress the occurrence of defects in the manufacturing process of the semiconductor device.

In order to improve the adhesion between the substrate and the adhesive layer or the film for forming a protective film provided on the substrate, the surface of the substrate may be subjected to embossing treatment such as blasting or solvent treatment; corona discharge treatment, electrons Oxidation treatment such as beam irradiation treatment, plasma treatment, ozone/ultraviolet irradiation treatment, flame treatment, chromic acid treatment, hot air treatment, and the like. Alternatively, the substrate surface may be subjected to a primer treatment.

‧Adhesive layer

A well-known adhesive layer can be suitably used for the said adhesive layer.

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

The thickness of the adhesive layer may be appropriately selected depending on the purpose, preferably from 1 μm to 100 μm, more preferably from 2 μm to 80 μm, still more preferably from 3 μm to 50 μm, and for example, any of 3 μm to 35 μm, 3 μm to 20 μm, and 3 μm to 10 μm. .

The adhesive layer may be composed of one layer (single layer) or multiple 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 plural layers may be the same or different from each other" means the same meaning as in the case of the above-mentioned support sheet.

In the case where the adhesive layer is composed of a plurality of layers, the total thickness of each layer may be the thickness of the above preferred adhesive layer.

Examples of the pressure-sensitive adhesive include an adhesive resin such as an acrylic resin, a urethane resin, a rubber resin, a polyoxymethylene resin, or a vinyl ether resin. In addition, when the adhesive is classified as a function of the function of the adhesive, for example, an energy ray-curable resin or the like can be mentioned.

In the present specification, the term "energy line" means an electromagnetic wave or a charged particle beam having an energy quantum, and examples of the energy line include ultraviolet rays, radiation, electron beams, and the like. Ultraviolet rays can be irradiated, for example, by using a high-pressure mercury lamp, a Fusion H-type lamp, a xenon lamp, a black light, or an LED (Light Emitting Diode) lamp. Shoot. The electron beam can illuminate an electron beam generated by an electron beam accelerator or the like.

In the present specification, the term "energy ray hardenability" means a property of being hardened by irradiation with an energy ray. The term "non-energy ray curability" means a property that does not harden even when irradiated with an energy ray.

The energy ray-curable resin may, for example, be a resin having a polymerizable group such as a (meth) acrylonitrile group or a vinyl group.

The adhesive resin is preferably an acrylic resin, and more preferably a (meth) acrylate copolymer containing a structural 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 is energy ray-curable, and the adhesion of the pressure-sensitive adhesive layer is lowered by irradiation of an energy ray. A semiconductor wafer with a protective film described later is picked up. Such an adhesive layer can be formed, for example, by using various adhesive compositions containing a component polymerized by irradiation of an energy ray.

<<Adhesive composition>>

As the preferable adhesive composition, an adhesive composition containing a component polymerized by irradiation with an energy ray is exemplified. Examples of such an adhesive composition include a composition containing an acrylic resin and an energy ray polymerizable compound (hereinafter sometimes referred to simply as "adhesive composition (i)"), and having a hydroxyl group and having a side chain. The composition of the acrylic resin and the isocyanate crosslinking agent of the polymerizable group (hereinafter, simply referred to as "adhesion" Agent composition (ii)") and the like. The acrylic resin having a hydroxyl group and a side chain having a polymerizable group is, for example, an acrylic resin having a hydroxyl group and having a polymerizable group in a side chain via a urethane bond.

<Adhesive Composition (i)>

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

Hereinafter, each component will be described.

[Acrylic resin]

The acrylic resin which is preferable as the adhesive composition (i) is, for example, a monomer obtained by using a (meth) acrylate and, if necessary, a (meth) acrylate other than a monomer, as a monomer. The obtained (meth) acrylate copolymer.

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, ( Methyl) propylene Cetyl acid ester (palmityl (meth) acrylate), heptadecyl (meth) acrylate, octadecyl (meth) acrylate (stearyl (meth) acrylate), (A) An alkyl (meth)acrylate having an alkyl group of an alkyl ester such as isodecyl acrylate (isostearyl (meth) acrylate) and having a chain structure of from 1 to 18; (meth)acrylic acid cycloalkyl ester such as isobornyl methyl methacrylate or 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) acrylonitrile An imine; a glycidyl group-containing (meth) acrylate such as glycidyl (meth)acrylate; hydroxymethyl (meth)acrylate; 2-hydroxyethyl (meth)acrylate; (meth)acrylic acid 2 -hydroxypropyl ester, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc. Hydroxy (meth) acrylate and 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 monomer (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 only 1 The species may be two or more.

The content of the acrylic resin in the adhesive composition (i) 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 (i). Mass% to 91% by mass.

[Energy ray polymerizable compound]

The energy ray-polymerizable compound is a compound which is hardened by polymerization by irradiation with an energy ray. Examples of the compound include a compound having an energy ray-polymerizable group such as 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.

More specifically, the energy ray polymerizable compound may, for example, be trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, pentaerythritol triacrylate, dipentaerythritol monohydroxypentaacrylate or dipentaerythritol. Acrylate such as hexaacrylate, 1,4-butanediol diacrylate or 1,6-hexanediol diacrylate; acrylic acid containing a cyclic aliphatic skeleton such as dicyclopentadiene dimethoxy diacrylate Ester; acrylate-based compound such as polyethylene glycol diacrylate, oligoester acrylate, urethane acrylate oligomer, epoxy-modified acrylate, polyether acrylate, itaconic acid oligomer, and the like.

The molecular weight of the 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 one type or two or more types.

The content of the energy ray polymerizable compound in 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 aforementioned photopolymerization initiator may be a known photopolymerization initiator.

Specific examples of the photopolymerization initiator include 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl) ketone, α-hydroxy-α, α'-di Methylacetophenone, 2-methyl-2-hydroxypropiophenone, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionate) Α-keto alcohol compounds such as benzyl-benzyl]phenyl}-2-methyl-propan-1-one; methoxyacetophenone, 2,2-dimethoxy-2-phenylphenethyl Acetone, 2,2-diethoxyacetophenone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinepropan-1-one a 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 chloride such as 2-naphthalene sulfonium chloride Compound; 1-benzophenone-1,1- Photoactive lanthanide compounds such as propylenedione-2-(o-ethoxycarbonyl)anthracene; benzophenone, benzamidine benzoic acid, 3,3'-dimethyl-4-methoxybenzophenone a benzophenone compound; thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2, a thioxanthone compound such as 4-dichlorothioxanthone, 2,4-diethylthioxanthone or 2,4-diisopropylthioxanthone; camphorquinone; halogenated ketone; fluorenylphosphine oxide; Phosphonic acid esters and the like.

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 in 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. When the content of the photopolymerization initiator is at least the above lower limit value, sufficient effects by using a photopolymerization initiator can be obtained. In addition, when the content of the photopolymerization initiator is less than or equal to the above upper limit, it is possible to suppress generation of by-products from an excessive amount of the photopolymerization initiator, thereby more effectively curing the pressure-sensitive adhesive layer.

[crosslinking agent]

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

As the crosslinking agent, for example, organic polyisocyanate can be mentioned. Compound, organic polyimine compound, and the like.

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

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; 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 polyhydric alcohols such as trimethylolpropane A compound of either or both of hexamethylene diisocyanate; an isocyanate diisocyanate or the like.

The organic polyimine compound may, for example, be N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide) or trimethylolpropane-tri-beta-nitrogen. Propidyl propionate, tetramethylolmethane-tri-β-aziridine propionate, N,N'-toluene-2,4-bis(1-aziridinecarbamamine) Based on 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 crosslinking structure can be easily introduced into the pressure-sensitive adhesive layer by the reaction of the isocyanate group with the hydroxyl group.

The amount of the crosslinking agent contained in the adhesive composition (i) may be one type or two or more types.

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

[solvent]

The adhesive composition (i) preferably further contains a solvent in addition to the acrylic resin and the energy ray polymerizable compound.

The solvent is not particularly limited.

Preferred examples of the solvent include hydrocarbons such as toluene and xylene; alcohols such as methanol, ethanol, 2-propanol, isobutanol (2-methylpropan-1-ol) and 1-butanol; and acetic acid; Ester such as ethyl ester; ketone such as acetone or methyl ethyl ketone; ether such as tetrahydrofuran; decylamine (compound having a guanamine bond) such as dimethylformamide or N-methylpyrrolidone.

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

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

[Other ingredients]

In addition to the acrylic resin and the energy ray polymerizable compound, the adhesive composition (i) may contain a photopolymerization initiator, a crosslinking agent, and a solvent, which are not in the range of the efficacy of the present invention. Other ingredients.

The other components described above may be known components, and may be arbitrarily selected according to the purpose, and are not particularly limited. Preferred examples of the other components include various additives such as a dye, a pigment, an anti-deterioration agent, an antistatic agent, a flame retardant, a polyoxyxene compound, and a chain transfer agent.

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 and an isocyanate crosslinking agent as essential components, and the acrylic resin has a hydroxyl group and a polymerizable group in a side chain. Here, as the acrylic resin, for example, an acrylic resin having a hydroxyl group and having a polymerizable group in a side chain via a urethane bond may be mentioned.

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

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 an acrylic resin obtained as follows: a (meth) acrylate having no hydroxyl group as a monomer (in the present specification, sometimes referred to as It is a hydroxyl group-free (meth) acrylate, and a hydroxyl group-containing (meth) acrylate (in this specification, sometimes referred to as "hydroxyl-containing (meth) acrylate)) The compound is copolymerized to obtain a hydroxyl group-containing copolymer, and the hydroxyl group of the obtained hydroxyl group-containing copolymer is reacted with an isocyanate group of a compound having an isocyanate group and a polymerizable group to form a urethane. The key is obtained to obtain an acrylic resin.

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

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

The hydroxyl group-free (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 one type or two or more types.

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

[Isocyanate crosslinking agent]

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

The isocyanate-based 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 adhesiveness of the adhesive layer after curing is lowered, and the peeling property from the adherend is improved, and the pick-up property of the semiconductor wafer with the protective film is improved. In addition, when the number of moles of the isocyanate group is at most the above upper limit, it is possible to further suppress generation of by-products due to reaction between the isocyanate-based crosslinking agents.

The content of the isocyanate crosslinking agent in the adhesive composition (ii) is preferably adjusted so that the number of moles of the isocyanate group is within the above range.

Further, the content of the isocyanate crosslinking agent in the adhesive composition (ii) satisfies the condition of the number of moles of the isocyanate group, and is preferably 0.01 part by mass based on 100 parts by mass of the acrylic resin. 20 parts by mass, more preferably 0.1 parts by mass to 15 parts by mass, even more preferably 0.3 parts by mass to 12 parts by mass.

[Photopolymerization initiator]

In the adhesive composition (ii), a photopolymerization initiator may be contained in addition to the acrylic resin and the isocyanate crosslinking agent.

The photopolymerization initiator is the same as the photopolymerization initiator 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 in the adhesive composition (ii) is preferably from 0.05 part by mass to 20 parts by mass based on 100 parts by mass of the acrylic resin. When the content of the photopolymerization initiator is at least the above lower limit value, sufficient effects by using a photopolymerization initiator can be obtained. In addition, when the content of the photopolymerization initiator is less than or equal to the above upper limit, it is possible to suppress generation of by-products from an excessive amount of the photopolymerization initiator, thereby more effectively curing the pressure-sensitive adhesive layer.

[solvent]

The adhesive composition (ii) preferably further contains a solvent in addition to the acrylic resin and the isocyanate crosslinking agent.

As the solvent, for example, the same solvent as in the case of the adhesive composition (i) can be mentioned.

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

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

[Other ingredients]

In the adhesive composition (ii), in addition to the acrylic resin and the isocyanate crosslinking agent, other components which do not conform to the photopolymerization initiator and the solvent may be contained within the range which does not impair the efficacy of the present invention.

As the other components, for example, the same components as in the case of the adhesive composition (i) can be mentioned.

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

Heretofore, the adhesive composition containing the component polymerized by the irradiation of the energy ray has been described. However, when the adhesive layer is formed, an adhesive composition containing no component polymerized by irradiation with the energy ray may be used. That is, the adhesive layer may be non-energy line hardenability without energy ray hardening.

For example, a composition containing an acrylic resin and a crosslinking agent (hereinafter, simply referred to as "adhesive composition (iii)") or the like is exemplified as the composition of the non-energy-curable adhesive. The adhesive composition (iii) may contain any components such as a solvent and other components that do not conform 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 the acrylic resin, the crosslinking agent, the solvent, and other components in the adhesive composition (i).

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

The content of the crosslinking agent in 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 above.

<<Manufacturing method of adhesive composition>>

The above-described adhesive composition such as the adhesive composition (i) to the adhesive composition (iii) can be obtained by using the above-mentioned adhesive, optionally, components other than the above-mentioned adhesive, etc. The components of the adhesive composition are formulated.

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

The method of mixing the components at the time of preparation is not particularly limited, and may be appropriately selected from the following known methods: the stirring of the stirring blade or the stirring blade is performed. a method of mixing; a method of mixing using a mixer; a method of applying ultrasonic waves for mixing, and the like.

The temperature and time when the components are added and mixed are not particularly limited as long as the respective components are not deteriorated, and 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 finally becomes a protective film having high impact resistance by curing. The protective film prevents, for example, cracking in the semiconductor wafer after the dicing step.

The film for forming a protective film can be formed by using a thermosetting protective film forming composition or an energy ray-curable protective film forming composition (hereinafter, collectively referred to as "protective film forming composition"). .

The film for forming a protective film may be only one layer (single layer), or may be 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 from each other, and the combination of the plurality of layers is There is no special limit.

The thickness of the film for forming a protective film is not particularly limited, but is preferably 1 μm to 100 μm, more preferably 5 μm to 75 μm, still more preferably 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, the thickness of the film for forming a protective film is the aforementioned upper limit value Hereinafter, 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

As a film for forming a thermosetting protective film, a film containing a polymer component (A) and a thermosetting component (B) is mentioned, for example. The polymer component (A) is considered to be a component 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 trigger of the reaction. Further, in the present invention, a polycondensation reaction is also included in the polymerization reaction.

<<Composition for forming a thermosetting protective film>>

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

The composition for forming a thermosetting protective film may be applied by a known method, and examples thereof include a method using the following various coaters: air knife coating Machine, knife coater, bar coater, gravure coater, roll coater, roll coater, curtain coater, die coater, knife coater, wire mesh A coater, a meyer bar coater, a contact coater, or the like.

The drying conditions of the thermosetting protective film-forming composition are not particularly limited. When the thermosetting protective film-forming composition contains a solvent to be described later, it is preferably heated and dried. The thermosetting protective film-forming composition containing a solvent is preferably dried at 70 ° C to 130 ° C for 10 seconds to 5 minutes, for example.

<Construction 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, The time is simply referred to as "the composition for forming a protective film (III-1)").

[Polymer component (A)]

The polymer component (A) is a polymer compound for imparting film forming properties 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, and when two or more types are used, The combinations and ratios of these may be arbitrarily selected.

As the polymer component (A), for example, an acrylic resin (with (meth)acrylonitrile-based resin), polyester, urethane-based resin (resin having urethane bond), urethane acrylate resin, polyoxynoxy resin (with hydrazine) The resin of the oxyalkylene bond, the rubber resin (resin having a rubber 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 (chronological stability during storage) of the film for forming a thermosetting protective film is improved. In addition, when the weight average molecular weight of the acrylic resin is 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 can be further suppressed from the adherend and the thermosetting protective film. A void or the like is formed between the films for 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 can be suppressed, and the peeling property of the support sheet can be improved. In addition, when the Tg of the acrylic resin is not more than the above 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 more kinds of (meth) acrylates; and a (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N- A copolymer of two or more kinds of monomers such as methylol acrylamide or the like.

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) acrylate A hexadecyl ester (palmityl (meth) acrylate), heptadecyl (meth) acrylate, octadecyl (meth) acrylate (stearyl (meth) acrylate), etc. The alkyl group has a carbon number of 1 18-chain (meth)acrylic acid alkyl ester; (meth)acrylic acid isobornyl ester, (meth)acrylic acid dicyclopentyl ester and the like (meth)acrylic acid cycloalkyl ester; (meth)acrylic acid benzyl ester An arylalkyl (meth)acrylate such as an ester; a cycloalkenyl (meth)acrylate such as dicyclopentenyl (meth)acrylate; a dicyclopentenyloxyethyl (meth)acrylate; a cycloalkyloxyalkyl acrylate; (meth) acrylimide; (methyl) a glycidyl group-containing (meth) acrylate such as glycidyl acrylate; hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, (A) Hydroxy-containing (meth)acrylic acid such as 3-hydroxypropyl acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate An ester; a (meth) acrylate containing a substituted amine group such as N-methylaminoethyl (meth)acrylate. 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 selected from (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N-methylol acrylamide, etc., in addition to the above (meth) acrylate. A resin obtained by copolymerizing one or more monomers.

The number of the monomers constituting the acrylic resin may be one or two or more. When two or more types are used, the combinations and ratios may be arbitrarily selected.

The acrylic resin may have a functional group which may be bonded to 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 in the acrylic resin may be bonded to another compound via a crosslinking agent (F) to be described later, or may be directly bonded to another compound without passing through the crosslinking agent (F). The acrylic resin is bonded to another compound via the functional group, and the package obtained by using the composite sheet for forming a protective film can be used. The tendency to improve.

In the present invention, 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 may be improved, or the film for forming a thermosetting protective film may easily follow the uneven surface of the adherend, thereby further suppressing adhesion to the adherend and heat hardening. Pores and the like are formed between the films for forming a 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 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, these may be used. The combination and ratio can be arbitrarily selected.

In the protective film forming composition (III-1), regardless of the polymer component (A) The content of the polymer component (A) (that is, the content of the polymer component (A) in the film for forming a thermosetting protective film) is preferably a ratio of the total content of all components other than the solvent. It is 5 mass% to 50 mass%, more preferably 10 mass% to 40 mass%, and particularly preferably 15 mass% to 35 mass%.

The polymer component (A) sometimes also conforms to the thermosetting component (B). In the present invention, when the protective film-forming composition (III-1) contains such a component that conforms to both the polymer component (A) and the thermosetting component (B), the protective film-forming composition ( III-1) can be regarded as containing a polymer component (A) and a thermosetting component (B).

[thermosetting 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 the above may be arbitrarily selected.

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

(epoxy thermosetting resin)

The epoxy thermosetting resin is composed of an epoxy resin (B1) and a thermosetting 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 one type or two or more types, and two or more types may be used. The combinations and ratios of the above may be arbitrarily selected.

‧Epoxy resin (B1)

Examples of the epoxy resin (B1) include known epoxy resins, and examples thereof include polyfunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ether and hydrogenated products thereof, and o-cresol novolac epoxy. Two or more epoxy resins such as resin, dicyclopentadiene type epoxy resin, biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, and phenyl skeleton type epoxy resin Compound.

As the epoxy resin (B1), an epoxy resin having an unsaturated hydrocarbon group can also be used. The epoxy resin having an unsaturated hydrocarbon group has higher compatibility with the acrylic resin than the 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 changed to have an unsaturated hydrocarbon group. The compound formed by the base. Such a compound is obtained, for example, by subjecting (meth)acrylic acid or a derivative thereof to an addition reaction with an epoxy group.

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

The unsaturated hydrocarbon group is a polymerizable unsaturated group, and specific examples of the unsaturated hydrocarbon group include a secondary ethyl group (vinyl group), a 2-propenyl group (allyl group), and a (meth)acryl fluorenyl group. The (meth) acrylamide group or the like is preferably an acrylonitrile group.

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

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 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 may be arbitrarily selected.

‧Hot hardener (B2)

The heat hardener (B2) functions as a hardener for the epoxy resin (B1).

The thermosetting agent (B2) is, for example, a compound having two or more functional groups reactive 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 a group in which an acid group is anhydride-formed. Preferably, the phenolic hydroxyl group, the amine group, or the acid group is anhydride-treated. 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 hardener (B2) may also have an unsaturated hydrocarbon group.

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

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

When using a phenolic hardener as a heat hardener (B2), it is guaranteed. The heat curing agent (B2) is preferably a phenolic curing agent having a softening point or a high glass transition temperature in terms of improving the peeling property of the film from the support sheet.

The heat hardener (B2) is preferably solid at normal temperature, and does not exhibit hardening activity for the epoxy resin (B1), on the other hand, dissolves by heating, and exhibits hardening activity to the epoxy resin (B1). A heat hardener (hereinafter may be simply referred to as "thermal active latent epoxy resin hardener").

The thermally active latent epoxy resin hardener is stably dispersed in the epoxy resin (B1) in a film for forming a thermosetting protective film at normal temperature, but is compatible with the epoxy resin (B1) by heating, and Reacts with epoxy resin (B1). By using the above-described thermally active latent epoxy resin hardener, the storage stability of the composite sheet for forming a protective film is remarkably improved. For example, it is possible to suppress the transfer of the curing agent from the film for forming a protective film to the adjacent support sheet, and it is possible to effectively suppress the decrease in the thermosetting property of the film for forming a thermosetting protective film. Further, since the film for forming a thermosetting protective film is heated to have a higher degree of thermal hardening, the pick-up property of the semiconductor wafer with a protective film described later is further improved.

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

In the thermal curing agent (B2), for example, the resin component such as a polyfunctional phenol resin, a novolak type phenol resin, a dicyclopentadiene type phenol resin, or an aralkyl phenol resin preferably has a number average molecular weight of 300 to 30,000, more preferably It is 400 to 10,000, and particularly preferably 500 to 3,000.

In the thermal curing 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 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). It is preferably 500 parts by mass, more preferably 1 part by mass to 200 parts by mass. When the content of the thermal curing agent (B2) is at least the above lower limit value, the film for forming a thermosetting protective film is more easily cured. In addition, when the content of the thermosetting agent (B2) is not more than the above-described upper limit, 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. .

The content of the thermosetting component (B) (for example, the total content of the epoxy resin (B1) and the thermosetting agent (B2) in the film for forming a protective film (III-1) and the film for forming a thermosetting protective film. 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. When the content of the thermosetting 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.

[hardening accelerator (C)]

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

Examples of preferred curing accelerators (C) include tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol; 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5- An imidazole such as hydroxymethylimidazole (an imidazole in which one or more hydrogen atoms are substituted by a group other than a hydrogen atom); an organic phosphine such as tributylphosphine, diphenylphosphine or triphenylphosphine (one or more) a phosphine in which a hydrogen atom is substituted with an organic group; a tetraphenylborate such as tetraphenylphosphonium tetraphenylborate or triphenylphosphine tetraphenylborate; and the like.

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

In the case of using the curing accelerator (C), the protective film-forming composition (III-1) and the thermosetting protective film-forming film have a curing accelerator (C) content relative to the thermosetting component (B). The content is 100 parts by mass, preferably 0.01 parts by mass to 10 parts by mass, more preferably 0.1 parts by mass to 5 parts by mass. When the content of the curing accelerator (C) is at least the above lower limit value, remarkable effects by the use of the curing accelerator (C) can be obtained. another In addition, when the content of the hardening accelerator (C) is equal to or less than the above-described upper limit, for example, the high-hardness curing accelerator (C) is inhibited from being formed in the film for forming a thermosetting protective film under high-temperature and high-humidity conditions. The effect of the segregation of the adhesive on the interface side and the segregation becomes high, 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). The film for forming a thermosetting protective film contains the filler (D), and the film obtained by curing the film for forming a thermosetting protective film is easily adjusted in thermal expansion coefficient. In addition, the thermal expansion coefficient is most suitable for the object to be formed of the protective film, and the reliability of the package obtained by using the composite sheet for forming a protective film is further improved. In addition, the film for forming a thermosetting protective film contains the filler (D), and 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, preferably an inorganic filler.

Examples of preferred inorganic fillers include powders of cerium oxide, aluminum oxide, talc, calcium carbonate, titanium white, iron oxide, tantalum carbide, and boron nitride; and the inorganic fillers are spheroidized. Beads; surface modifiers of such inorganic fillers; single crystal fibers of such inorganic fillers; glass fibers, and the like.

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

The filler (D) 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 combinations and ratios can be arbitrarily selected.

In the case of using the filler (D), the content of the filler (D) in the protective film-forming composition (III-1) (that is, the filler (D) in the film for forming a thermosetting protective film. The ratio of the content of the total content of all components other than the solvent is preferably from 5% by mass to 80% by mass, more preferably from 7% by mass to 60% by mass. By the content of the filler (D) being such a range, it is easier to adjust the above 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 compound having a functional group reactive 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) does not impair the heat resistance and the water resistance is improved.

The coupling agent (E) is preferably a compound having a functional group reactive with a functional group of 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-condensed sugar. Oloxypropyltrimethoxydecane, 3-glycidoxypropylmethyldiethoxydecane, 3-glycidoxypropyltriethoxydecane, 3-glycidoxymethyldiethyl Oxydecane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxydecane, 3-methylpropenyloxypropyltrimethoxydecane, 3-aminopropyltrimethoxydecane, 3 -(2-Aminoethylamino)propyltrimethoxydecane, 3-(2-aminoethylamino)propylmethyldiethoxydecane, 3-(phenylamino)propyl Trimethoxydecane, 3-anilinopropyltrimethoxydecane, 3-ureidopropyltriethoxydecane, 3-mercaptopropyltrimethoxydecane, 3-mercaptopropylmethyldimethoxydecane , bis(3-triethoxydecylpropyl)tetrasulfide, methyltrimethoxydecane, methyltriethoxydecane, vinyltrimethoxydecane, vinyltriethoxydecane,imidazole Decane and so on.

When the protective film-forming composition (III-1) and the film for forming a thermosetting protective film are contained in the film, the coupling agent (E) may be used alone or in combination of two or more kinds. The combinations and ratios can be arbitrarily selected.

In the case of using the coupling agent (E), the composition for forming a protective film (III-1) and the film for forming a thermosetting protective film, the content of the coupling agent (E) relative to the polymer component (A) and heat The total content of the curable component (B) is 100 parts by mass, preferably 0.03 part by mass to 20 parts by mass, more preferably 0.05 part by mass to 10 parts by mass, still more preferably 0.1 part by mass to 5 parts by mass. When the content of the coupling agent (E) is at least the above lower limit value, a more remarkable effect by using the coupling agent (E) can be obtained: the dispersibility of the filler (D) in the resin is improved, or Film for forming a thermosetting protective film and an adherend Then improve and so on. Further, when the content of the coupling agent (E) is at most the above upper limit value, generation of outgas can be further suppressed.

[crosslinking agent (F)]

The use of the above-mentioned acrylic resin having a functional group bondable with another compound, such as a vinyl group, a (meth) acryl fluorenyl group, an amine group, a hydroxyl group, a carboxyl group, an isocyanate group or the like as the polymer component (A) In the case of the protective film-forming composition (III-1) and the thermosetting protective film-forming film, the crosslinking agent (F) may be contained. The crosslinking agent (F) is a component for crosslinking the above-mentioned functional group in the polymer component (A) by bonding with another compound, and by crosslinking in this way, the film for forming a thermosetting protective film can be adjusted. The initial strength and cohesion.

Examples of the crosslinking agent (F) include an organic polyvalent isocyanate compound, an organic polyimine compound, a metal chelate crosslinking agent (a crosslinking agent having a metal chelate structure), and an aziridine crosslinking. A reagent (a cross-linking 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 collectively referred to simply as "aromatic polyisocyanate compounds"). a trimer, an isocyanurate body, and an adduct of the above aromatic polyvalent isocyanate compound; and the aromatic polyisocyanate compound and the like and a polyol compound A terminal isocyanate urethane prepolymer obtained by the reaction or the like. The term "adduct" means the aforementioned aromatic polyisocyanate compound, aliphatic polyisocyanate compound or alicyclic polyisocyanate compound, and is contained in ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane or castor oil. A reactant of a low molecular weight active hydrogen compound. Examples of the adducts include a benzodimethyl diisocyanate adduct of trimethylolpropane described later. 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; 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 polyhydric alcohols such as trimethylolpropane A compound obtained by using one or more of hexamethylene diisocyanate and benzodimethyl diisocyanate; an isocyanuric acid diisocyanate or the like.

The organic polyimine compound may, for example, be N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide) or trimethylolpropane-tri-beta-nitrogen. Propidyl propionate, tetramethylolmethane-tri-β-aziridine propionate, N,N'-toluene-2,4-bis(1-aziridinecarbamamine) Melamine Wait.

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, the crosslinking structure can be easily introduced by reacting the crosslinking agent (F) with the polymer component (A). In the film for forming a thermosetting protective film.

The crosslinking agent (F) 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 when two or more types are used, The combinations and ratios of these may be arbitrarily selected.

In the case of using the crosslinking agent (F), the content of the crosslinking agent (F) in the protective film-forming composition (III-1) is preferably 100 parts by mass based on the content of the polymer component (A). 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. When the content of the crosslinking agent (F) is at least the above lower limit value, a more remarkable effect by the use of the crosslinking agent (F) can be obtained. In addition, when the content of the crosslinking agent (F) is at most the above-mentioned upper limit, the adhesion between the film for forming a thermosetting protective film and the support sheet, or the film for forming a thermosetting protective film and the semiconductor wafer or The adhesion of the semiconductor wafer is excessively reduced.

In the present invention, the effects of the present invention can be sufficiently obtained 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 contains an energy ray-curable resin (G), and the characteristics can be changed by irradiating the energy ray.

The energy ray-curable resin (G) is obtained by polymerizing (hardening) 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 (meth) acrylate containing a chain aliphatic skeleton such as (meth) acrylate; (meth) acrylate containing a cyclic aliphatic skeleton such as dicyclopentanyl (meth) acrylate; polyethylene glycol Poly(alkyl) diol (meth) acrylate such as di(meth) acrylate; oligoester (meth) acrylate; (meth) acrylate urethane oligomer; epoxy modification (A) a acrylate; a polyether (meth) acrylate other than the above-mentioned polyalkylene glycol (meth) acrylate; an itaconic acid oligomer or the like.

The weight average molecular weight of the aforementioned 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 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 used. Can be chosen at will.

When the energy ray-curable resin (G) is used, the content of the energy ray-curable resin (G) in the protective film-forming composition (III-1) is preferably from 1% by mass to 95% by mass, more preferably It is 2% by mass to 90% by mass, and particularly preferably 3% by mass to 85% by mass.

[Photopolymerization initiator (H)]

When the energy ray-curable resin (G) is contained in the protective film-forming composition (III-1), the photo-curable resin (G) may be contained in a highly efficient polymerization reaction. (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 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 used. Can be chosen at will.

In the case of using the photopolymerization initiator (H), the content of the photopolymerization initiator (H) in the protective film-forming composition (III-1) is 100% with respect to the energy ray-curable resin (G). The parts by mass are preferably from 0.1 part by mass to 20 parts by mass, more preferably from 1 part by mass to 10 parts by mass, even more preferably from 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 coloring agent 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 croconium dye, a squalilium dye, and an anthraquinone. Pigment, polymethine dye, naphthoquinone dye, pyranthene dye, phthalocyanine dye, naphthalocyanine dye, naphthalene amide dye, azo dye, condensed azo dye, indigo pigment , perinone pigment, anthraquinone dye, dioxane dye, quinacridone dye, isoindolinone color Quinophthalone pigment, pyrrole dye, thioindigo dye, metal complex dye (metal stray salt dye), dithiol metal complex dye, phenol pigment, A triallyl methane-based dye, an anthraquinone-based dye, a naphthol-based dye, a methine-azo dye, a benzimidazolone dye, a dermoside-based dye, and a threne-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 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 combinations and ratios can be arbitrarily selected.

In the case of using the coloring agent (I), the content of the coloring agent (I) in the film for forming a thermosetting protective film may be appropriately adjusted depending on the purpose. For example, the protective film may be printed by laser irradiation, and the content of the coloring agent (I) in the film for forming a thermosetting protective film may be adjusted to adjust the light transmittance of the protective film, thereby improving the print visibility. In addition, by adjusting the content of the coloring agent (I) in the film for forming a thermosetting protective film, the design property of the protective film can be improved, and the polishing trace on the back surface of the semiconductor wafer can be made difficult. In consideration of this aspect, the content of the coloring agent (I) in the protective film forming composition (III-1) (also In other words, the ratio of the content of the coloring agent (I) in the film for forming a thermosetting protective film to the total content of all the components other than the solvent is preferably from 0.1% by mass to 10% by mass, more preferably from 0.1% by mass to 7.5 mass%, particularly preferably from 0.1% by mass to 5% by mass, for example, may be from 0.1% by mass to 3% by mass and from 0.1% by mass to 1% by mass. When the content of the coloring agent (I) is at least the above lower limit value, a more remarkable effect by the use of the coloring agent (I) can be obtained. In addition, when the content of the coloring agent (I) is at most the above upper limit value, the light transmittance of the film for forming a thermosetting protective film can be suppressed from being excessively lowered.

[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 the range in which the effects of the present invention are not impaired.

The general-purpose additive (J) may be a known additive, and may be arbitrarily selected according to the purpose, and is not particularly limited. Examples of preferred general-purpose additives (J) include a plasticizer, an antistatic agent, an antioxidant, and a getter. (gettering agent) and so on.

The general-purpose additive (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 combinations and ratios can be arbitrarily selected.

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

Preferred examples of the solvent include hydrocarbons such as toluene and xylene; alcohols such as methanol, ethanol, 2-propanol, isobutanol (2-methylpropan-1-ol) and 1-butanol; and acetic acid; Ester such as ethyl ester or butyl acetate; ketone such as acetone or methyl ethyl ketone; ether such as tetrahydrofuran; decylamine (compound having a guanamine bond) such as dimethylformamide or N-methylpyrrolidone.

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 combinations and ratios can 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 added at the same time.

In the case of using a solvent, it can be used by, ie, The solvent may be mixed with any of the formulation components other than the solvent to preliminarily dilute the formulation component, or may be used by mixing the solvent with the formulation component without preliminarily diluting any of the formulation components other than the solvent.

The method of mixing the components at the time of preparation is not particularly limited, and may be appropriately selected from the following known methods: a method of mixing by stirring a stirring blade or a stirring blade, a method of mixing using a mixer, and applying ultrasonic waves for mixing. Method and so on.

The temperature and time when the components are added and mixed are not particularly limited as long as the respective components are not deteriorated, and it is preferably 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 an energy ray-curable component (a).

The energy ray-curable component (a) is preferably uncured, preferably adhesive, more preferably uncured and adhesive. Here, the "energy line" and the "energy line hardenability" 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 a constituent material of the film. For example, a composition for forming an energy ray-curable protective film is applied to a surface to be formed of a film for forming an energy ray-curable protective film, and if necessary, it is dried, whereby an energy ray-curable protective film can be formed at a target portion. membrane. Energy line The content ratio of the components which are not vaporized at normal temperature in the composition for forming a curable protective film is usually the same as the content ratio of the components in the film for forming an energy ray-curable protective film. Here, the "normal temperature" is as described above.

The energy ray-curable protective film-forming composition may be applied by a known method, and examples thereof include the following various coaters: air knife coater, knife coater, bar coater, and gravure coat. Cloth machine, roll coater, roll coater, curtain coater, die coater, knife coater, screen coater, wire bar coater, contact coating Cloth machine, etc.

The drying condition of the energy ray-curable protective film-forming composition is not particularly limited. When the energy ray-curable protective film-forming composition contains a solvent to be described later, it is preferably heated and dried. The composition for forming an energy ray-curable protective film containing a solvent is preferably dried at 70 ° C to 130 ° C for 10 seconds to 5 minutes, for example.

<Construction film forming composition (IV-1)>

For example, the energy ray-curable protective film-forming composition (IV-1) containing the energy ray-curable component (a) may be used. It is "the composition (IV-1) for protective film formation").

[Energy line hardening component (a)]

The energy ray-curable component (a) is a component which is formed by irradiation of an energy ray, and is used 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 and having a weight average molecular weight of 80,000 to 2,000,000, and a compound having an energy ray-curable group and having a molecular weight of 100 to 80,000. (a2). The polymer (a1) may be crosslinked by at least a part of the polymer by a crosslinking agent or may not be crosslinked.

(Polymer (a1) having an energy ray-hardening group and having a weight average molecular weight of 80,000 to 2,000,000)

The polymer (a1) having an energy ray-curable group and having a weight average molecular weight of 80,000 to 2,000,000 includes, for example, an acrylic resin (a1-1) which is an acrylic polymer ( A11) is an addition reaction with an energy ray-curable compound (a12) having a functional group reactive with a group of another compound, and the energy ray-curable compound (a12) has An energy ray-curable group such as a group reactive with the aforementioned functional group and an energy ray-curable double bond.

Examples of the functional group which can react 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 by a group other than a hydrogen atom) Base), epoxy group, and the like. However, 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 above functional group is preferably a hydroxyl group.

‧Acrylic polymer with functional group (a11)

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

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

Examples of the acrylic monomer having a 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-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc.; hydroxyalkyl (meth)acrylate; vinyl alcohol, A non-(meth)acrylic unsaturated alcohol such as allyl alcohol (an unsaturated alcohol having no (meth) acrylonitrile skeleton) or the like.

Examples of the carboxyl group-containing monomer include (meth) propylene. An ethylenically unsaturated monocarboxylic acid such as an acid or a crotonic acid (a monocarboxylic acid having an ethylenically unsaturated bond); an ethylenically unsaturated dicarboxylic acid such as fumaric acid, itaconic acid, maleic acid or citraconic acid ( a dicarboxylic acid having an ethylenically unsaturated bond; an anhydride of the ethylenically unsaturated dicarboxylic acid; a carboxyalkyl (meth)acrylate such as 2-carboxyethyl methacrylate;

The acrylic monomer having a 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 constituting the acrylic polymer (a11) may be one type or two or more types. When two or more types are used, the combinations and ratios may be arbitrarily selected. .

Examples of the acrylic monomer having no functional group include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, and isopropyl (meth)acrylate. N-butyl (meth)acrylate, isobutyl (meth)acrylate, second butyl (meth)acrylate, tert-butyl (meth)acrylate, amyl (meth)acrylate, (methyl) Hexyl acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-decyl (meth)acrylate , isodecyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth) acrylate, lauryl (meth) acrylate (lauryl (meth) acrylate), ( Tridecyl methyl methacrylate, tetradecyl (meth) acrylate (myristyl (meth) acrylate), pentadecyl (meth) acrylate, (meth) propylene Cetyl ester (palmityl (meth)acrylate), heptadecyl (meth)acrylate, octadecyl (meth)acrylate (stearyl (meth)acrylate), etc. The alkyl group of the base ester is an alkyl (meth)acrylate or the like having a chain structure of 1 to 18 carbon atoms.

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

The acrylic monomer having no functional group in the acrylic polymer (a11) may be one type or two or more types. When two or more types are used, the combinations and ratios may be any. 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 of the amount of the structural unit derived from the functional group-containing acrylic monomer to the total amount of the structural unit constituting the acrylic polymer (a11) is preferably It is from 0.1% by mass to 50% by mass, more preferably from 1% by mass to 40% by mass, even more preferably from 3% by mass to 30% by mass. When the ratio is in such a range, the energy ray-curable group in the acrylic resin (a1-1) obtained by copolymerization of the acrylic polymer (a11) and the energy ray-curable compound (a12) can be used. The content is easily adjusted to a range in which the degree of hardening of the protective film is better.

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 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 3% by mass. % to 20% by mass.

‧Energy line hardening 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 compatible with the acrylic polymer (a11). The group of the functional group reaction is more preferably an isocyanate group as the above group. The energy ray-curable compound (a12) has, for example, an isocyanate group as the aforementioned group In this case, the isocyanate group is easily reacted with the hydroxyl group of the acrylic polymer (a11) having a hydroxyl group as a 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, m-isopropenyl-α, α-dimethylbenzyl isocyanate, and methacryl Isocyanate, allyl isocyanate, 1,1-(bispropenyloxymethyl)ethyl isocyanate; by reaction of a diisocyanate compound or a polyisocyanate compound with hydroxyethyl (meth)acrylate The obtained acrylonitrile-based monoisocyanate compound; an acrylonitrile-based monoisocyanate compound obtained by a reaction of a diisocyanate compound or a polyisocyanate compound, a polyol compound, and a 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 combinations and ratios may be arbitrary. select.

The acrylic resin (a1-1) is derived from the aforementioned energy ray curability The ratio of the content of the energy ray-curable group of the compound (a12) to the content of the aforementioned functional group derived from the acrylic polymer (a11) is preferably from 20 mol% to 120 mol%, more preferably 35 mol. Ears are from 100% to 100% by mole, particularly preferably from 50% to 100% by mole. By the ratio of the above content being such a range, the adhesion force of the cured protective film is further increased. In the case where the energy ray-curable compound (a12) is a monofunctional compound (having one of the above-mentioned groups in one molecule), the upper limit of the ratio of the content is 100 mol%, but the energy is When the linear curable compound (a12) is a polyfunctional (having two or more of the above-mentioned groups in one molecule), the upper limit of the ratio of the above content may exceed 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.

When at least a part of the polymer (a1) is crosslinked by a crosslinking agent, the polymer (a1) may be any one of the monomers constituting the acrylic polymer (a11) which does not conform to the above description and The monomer having a group reactive with the crosslinking agent is polymerized, crosslinked in the group reactive with the crosslinking agent, or may be reacted with the aforementioned functional group derived from the energy ray-curable compound (a12). Crosslinking in the middle.

The polymer (a1) 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 types. The above combinations and ratios can be arbitrarily selected in the case of two or more types.

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

Examples of the energy ray-curable group in the compound (a2) having an energy ray-curable group and having a molecular weight of from 100 to 80,000 include a group containing an energy ray-curable double bond, and preferred examples of the group include (A) Base) acrylonitrile, vinyl, and the like.

When the compound (a2) satisfies the above conditions, it is not particularly limited, 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. Wait.

In the compound (a2), the low molecular weight compound having an energy ray-curable group may, for example, be a polyfunctional monomer or oligomer, and is preferably an acrylate-based 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) Ethoxylated benzene 茀, 2,2-bis[4-((meth)acryloxypolypropoxy)phenyl]propane, tricyclodecane dimethanol di(meth) acrylate, 1,10-癸2 Alcohol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, dipropylene glycol di(meth)acrylate, three Propylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polybutylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(methyl) Acrylate, triethylene glycol di(meth)acrylate, 2,2-bis[4-((meth)propenyloxyethoxy)phenyl]propane, neopentyl glycol di(methyl) a bifunctional (meth) acrylate such as acrylate, ethoxylated polypropylene glycol di(meth) acrylate or 2-hydroxy-1,3-di(methyl) propylene decyloxypropane; isocyanuric acid Tris(2-(meth)acryloxyethyl)ester, ε-caprolactone modified tris-(2-(methyl)propenyloxyethyl) isocyanurate, ethoxylation Tris(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, di-trimethylolpropane Tetrakis (meth) acrylate, ethoxylated pentaerythritol tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol poly (meth) acrylate, dipentaerythritol hexa (meth) acrylate, etc. A polyfunctional (meth) acrylate oligomer such as a polyfunctional (meth) acrylate or a (meth) acrylate urethane oligomer.

In the above-mentioned compound (a2), as the epoxy resin having an energy ray-curable group or a phenol resin having an energy ray-curable group, for example, paragraph 0043 in "Japanese Patent Laid-Open Publication No. 2013-194102" can be used. Resin. Such a resin also conforms to a resin constituting a thermosetting component to be described later, but in the present invention, it is regarded as the above compound (a2).

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 may be arbitrarily selected.

[Polymer without energy line hardening group (b)]

In the case where 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 no Energy ray-hardening group polymer (b).

The polymer (b) may be crosslinked by at least a part of a crosslinking agent or may not be crosslinked.

Examples of the polymer (b) having no energy ray-curable group include an acrylic polymer, a phenoxy resin, a urethane resin, a polyester, a rubber resin, and an urethane urethane resin. Wait.

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

The acrylic polymer (b-1) may be a known polymer, and may be, for example, 1 The homopolymer of the acrylic monomer may be a copolymer of two or more kinds of acrylic monomers, or one or two or more kinds of acrylic monomers and one or more kinds of acrylic monomers. a copolymer of a monomer (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 methacrylate, isobutyl (meth)acrylate, second butyl (meth)acrylate, tert-butyl (meth)acrylate, amyl (meth)acrylate, (meth)acrylic acid Hexyl ester, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-decyl (meth)acrylate, Isodecyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauryl (meth)acrylate), (A) Tridecyl acrylate, tetradecyl (meth) acrylate (myristyl (meth) acrylate), pentadecyl (meth) acrylate, cetyl (meth) acrylate An ester (palmityl (meth)acrylate), heptadecyl (meth)acrylate, octadecyl (meth)acrylate (stearyl (meth)acrylate), etc. The alkyl group is an alkyl (meth)acrylate having a chain structure of 1 to 18 carbon atoms or the like.

Examples of the (meth) acrylate having a cyclic skeleton include (meth)acrylic acid cycloalkyl esters such as isobornyl (meth)acrylate and dicyclopentanyl (meth)acrylate; Arylalkyl (meth)acrylate such as benzyl acrylate; cycloalkenyl (meth) acrylate such as dicyclopentenyl (meth)acrylate; dicyclopentenyloxyethyl (meth)acrylate (meth)acrylic cycloalkenyloxyalkyl ester and 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, 2-hydroxybutyl (meth) 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.

As the polymer (b) which is at least partially crosslinked by a crosslinking agent and does not have the aforementioned energy ray-curable group, for example, polymerization of a reactive functional group in the polymer (b) and a crosslinking agent may be mentioned. Things.

The reactive functional group is appropriately selected depending on the type of the crosslinking agent and the like, and is not particularly limited. 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, examples of the reactive functional group include a carboxyl group, an amine group, a guanamine group, etc., among which, it is preferred to have high reactivity with an epoxy group. Carboxyl group. However, 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.

The polymer (b) having the reactive functional group and having no energy ray-curable group may, for example, be a polymer obtained by polymerizing at least a monomer having the reactive functional group. In the case of the acrylic polymer (b-1), either or both of the acrylic monomer and the non-acrylic monomer exemplified as the monomer constituting the acrylic polymer (b-1) A monomer having the aforementioned reactive functional group may be used. The polymer (b) having a hydroxyl group as a reactive functional group may, for example, be a polymer obtained by polymerizing a hydroxyl group-containing (meth) acrylate, and may be exemplified above. A polymer obtained by polymerizing a monomer in which one or two or more hydrogen atoms of the acrylic monomer or non-acrylic monomer are substituted with the reactive functional group.

In the aforementioned polymer (b) having a reactive functional group, the ratio of the amount of the structural unit derived from the monomer having a reactive functional group to the total amount of the structural unit constituting the polymer (b) is higher It is preferably from 1% by mass to 20% by mass, more preferably from 2% by mass to 10% by mass. By the above ratio being such a range, in the polymer (b), the degree of crosslinking is in a more preferable range.

The weight average molecular weight (Mw) of the polymer (b) having no energy ray-curable group is preferably from 10,000 to 2,000,000, in terms of the film forming property of the protective film-forming composition (IV-1) being more excellent. More preferably, it is 100,000 to 1,500,000. Here, the "weight average molecular weight" is as described above.

The polymer (b) having no energy ray-curable group contained in the film for forming a protective film (IV-1) and the film for forming an energy ray-curable protective film may be used alone or in combination of two or more kinds. When two or more types are used, the combinations and ratios can be arbitrarily selected.

The composition (IV-1) for forming a protective film includes 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, Jia further contains the aforementioned (a1). Further, the protective film-forming composition (IV-1) may not contain the compound (a2), and may contain the polymer (a1) together and no energy ray-curable group. Polymer (b).

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 protective film-forming composition ( In the above IV-1), the content of the compound (a2) is preferably from 10 parts by mass to 100 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. The parts by mass are more preferably from 30 parts by mass to 350 parts by mass.

In the protective film-forming composition (IV-1), the total content of the energy ray-curable component (a) and the polymer (b) having no energy ray-curable group (that is, the energy ray-curable protective film formation) The ratio of the total content of the energy ray-curable component (a) and the polymer (b) having no energy ray-curable group in the film to the total content of components other than the solvent is preferably 5% by mass to 90%. The mass% is more preferably from 10% by mass to 80% by mass, particularly 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 hardenability 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, and a crosslinking agent, depending on the purpose. One or two or more of the group consisting of a coloring agent and a general-purpose additive. For example, by using a protective film containing the aforementioned energy ray hardening component and thermosetting component The film for forming the composition (IV-1), the film for forming an energy ray-curable protective film formed by the film is formed by a coating film for forming an energy ray-curable protective film by heating. The strength is also improved.

The thermosetting component, the photopolymerization initiator, the filler, the coupling agent, the crosslinking agent, the colorant, and the general-purpose additive in the composition for forming a protective film (IV-1) may be respectively formed into a protective film. The thermosetting component (B), the photopolymerization initiator (H), the filler (D), the coupling agent (E), the crosslinking agent (F), and the coloring agent (I) in the composition (III-1) ) and the same compound as the general additive (J).

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. When two or more types are used in combination, the combinations and ratios can be arbitrarily selected.

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

In order to improve the workability of the composition by dilution, the protective film-forming composition (IV-1) preferably further contains a solvent.

The solvent contained in the protective film-forming composition (IV-1) is, for example, the same solvent 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) can be 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 added at the same time.

When a solvent is used, it may be used by mixing a solvent with any of the formulation components other than the solvent to preliminarily dilute the formulation component; or by using the solvent in the following manner, that is, not using the solvent Any of the other ingredients to be mixed is previously diluted to mix the solvent with the ingredients.

The method of mixing the components at the time of preparation is not particularly limited, and may be appropriately selected from the following known methods: a method of mixing by stirring a stirring blade or a stirring blade, a method of mixing using a mixer, and applying ultrasonic waves for mixing. Method and so on.

The temperature and time when the components are added and mixed are not particularly limited as long as the respective components are not deteriorated, and it is preferably adjusted, and the temperature is preferably from 15 ° C to 30 ° C.

○ coating

Regarding the foregoing coating layer, as long as the surface roughness Ra of the surface on the opposite side to the side in contact with the support sheet in the coating layer is smaller than that in the support sheet The surface roughness Ra of the surface on the side of the layer is not particularly limited.

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

The composite sheet for forming a protective film has not only a function of forming a back surface of a semiconductor wafer for protecting a dicing film, but also a function as a dicing sheet for dicing 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 extended. 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, it is preferable that the coating layer is formed so that the composition which is a raw material is hardened by irradiation with an energy ray, and is not thermally hardened.

The thickness of the aforementioned 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 opposite side to the side in contact with the support sheet in the coating layer is more easily lowered, and the composite sheet for forming a protective film is further suppressed. The effect of the adhesion becomes higher. In addition, since the thickness of the coating layer is equal to or less than the aforementioned upper limit value, When the state of the semiconductor wafer to which the composite sheet for protective film formation is attached is detected by an infrared camera or the like through the above-described sheet, a clearer detection image can be obtained, and the semiconductor wafer can be more easily extended and diced.

Further, since the coating layer covers the uneven surface of the support sheet as described above, the contact surface with the support sheet can be an uneven surface, and in the portion including the convex portion in the uneven surface of the coating layer, the thickness of the coating layer can be The tip of the convex portion was calculated as a point together.

The surface roughness Ra of the surface on the opposite side to the side in contact with the support sheet in the coating layer 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. the following. By the surface roughness Ra of the coating layer being 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 opposite side to the side in contact with the support sheet in the coating layer is not particularly limited, and may be, for example, 0.005 μm or the like.

That is, the surface roughness Ra may be, for example, preferably from 0.005 μm to 0.5 μm, more preferably from 0.005 μm to 0.4 μm, still more preferably from 0.005 μm to 0.3 μm, still more preferably from 0.005 μm to 0.2 μm.

The surface roughness Ra of the coating layer can be, for example, the surface roughness Ra of the surface of the support sheet in the support sheet, the thickness of the coating layer, the coating method for forming the coating layer described later, and the like. Make adjustments.

With respect to the foregoing coating layer, the value of [thickness (μm) of the coating layer / [surface roughness Ra (μm) of the surface of the side of the support sheet in the support sheet] is preferably from 0.1 to 30, more preferably from 0.3 to 20, especially preferably 0.5 to 10. When the value is more than or equal to the above lower limit value, the surface roughness Ra of the surface on the opposite side to the side in contact with the support sheet in the coating layer becomes smaller. Therefore, the protective film can be laser-printed more clearly, and the effect of suppressing the adhesion of the above-mentioned composite film for forming a protective film becomes higher. Further, by the aforementioned value being equal to or less than the above upper limit value, the thickness of the coating layer can be prevented from being excessively thick.

The gloss value of the surface of the aforementioned coating on the side opposite to the side of the support sheet (the aforementioned support sheet side) is preferably from 32 to 95, more preferably from 40 to 90, still more preferably from 45 to 85, for example, 50 to 80. By the aforementioned gloss value of the coating being such a range, the protective film can be more clearly subjected to laser printing. In addition, when the thickness of the coating layer is greater than or equal to the above-described lower limit value, the state of the semiconductor wafer to which the composite sheet for forming a protective film is attached is detected by an infrared camera or the like, and a clearer state can be obtained. Detect images. Further, when the gloss value of the coating layer is equal to or less than the above upper limit value, and the state of the semiconductor wafer is detected in the same manner, the phenomenon in which the coating layer is brightened can be suppressed, and the image can be more easily recognized by an infrared camera or the like.

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

Determination of haze from the side of the coating layer of the composite sheet for forming a protective film The value is preferably 47% or less, more preferably 1% to 47%, still 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, scattering of light can be 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 composite sheet for protective film formation is attached is detected by an infrared camera or the like, a clearer detection image can be obtained. Here, the measured value of the haze of the composite sheet for forming a protective film is measured by the direction of the surface opposite to the side in contact with the support sheet in the composite sheet for forming a protective film. The haze value.

Further, the haze is a value obtained by measurement in accordance with JIS K 7136.

Various characteristics such as the gloss value of the coating layer can be adjusted, for example, by the thickness of the coating layer, the composition of the coating composition to form a coating layer described later, and the like.

The measured value of the haze from the coating side of the composite sheet for forming a protective film can be, for example, a thickness of each layer of the composite sheet for forming a protective film by a coating layer or a support sheet or the like, and a composition for forming the respective layers ( For example, the components and the like of the coating composition described later are adjusted.

<<Coating composition>>

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

[ingredient (α)]

The component (α) is used to reduce the refractive index of the coating layer, and to reduce the hardenability and heat-shrinkability of the composite sheet for forming a protective film, thereby suppressing the composite sheet for forming a protective film due to the shrinkage. Curl is produced in the middle.

Examples of the cerium oxide sol in the component (α) include colloidal cerium oxide, and the colloidal cerium oxide-based cerium oxide microparticles are in an organic solvent such as an alcohol or an ether derived from ethylene glycol (cellosolve). The colloidal state is suspended. The average particle diameter of the aforementioned cerium oxide microparticles suspended is preferably from 0.001 μm to 1 μm, more preferably from 0.03 μm to 0.05 μm.

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

The cerium oxide microparticles to which the radical polymerizable unsaturated group-containing organic compound is bonded, for example, may be exemplified by a decyl alcohol group and a radical polymerizable unsaturated group-containing organic compound present on the surface of the cerium oxide microparticles. The particles obtained by reacting the functional groups preferably have an average particle diameter of from 0.005 μm to 1 μm. Free radical polymerization The aforementioned functional group in the organic compound of the group is not particularly limited as long as it can react with the aforementioned stanol group in the ceria 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).

(wherein 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 in R ² include a chlorine atom, a bromine atom, and an iodine atom.

Examples of the preferred radical polymerizable unsaturated group-containing organic compound include (meth)acrylic acid, (meth)acrylonitrile chloride, 2-isocyanate ethyl (meth)acrylate, and (methyl). ) glycidyl acrylate, 2,3-iminopropyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, (3-(meth)acryloxypropyl)trimethoxydecane, and the like.

In the present invention, the organic compound containing a radical polymerizable unsaturated group may be used singly or in combination of two or more.

In the component (α), the cerium oxide sol and the cerium oxide fine particles to which the organic compound having a radical polymerizable unsaturated group is 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, and the cerium oxide sol and the aforementioned bonding may be used in combination. A cerium oxide microparticle having an organic compound containing a radical polymerizable unsaturated group.

The content of the component (α) in the coating composition is preferably selected according to the refractive index of the support sheet, and it is usually preferred that the content of the cerium oxide derived from the component (α) in the coating layer is 20 The amount of 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 suppressing the occurrence of curling in the composite sheet for forming a protective film become higher. Further, when the content of the cerium oxide is at most the above upper limit value, the coating layer is more easily formed, and the effect of suppressing the decrease in the hardness of the coating layer becomes higher.

The refractive index, ease of formation and hardness of the above coating, and inhibition The content of the cerium oxide derived from the component (α) in the coating layer is more preferably from 20% by mass to 45% by mass in terms of the fact that the property of generating curl in the composite sheet for forming a protective film becomes better.

[ingredient (β)]

The aforementioned component (β) is a main photocurable component that forms the aforementioned coating layer.

The polyfunctional acrylate monomer in 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 neopentane. Glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, Lactone modified dicyclopentenyl di(meth)acrylate, ethylene oxide modified di(meth)acrylate, allylated cyclohexyl di(meth)acrylate, isocyanurate Di(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, propionic acid modified dipentaerythritol tri(meth)acrylate, pentaerythritol tris(methyl) Acrylate, propylene oxide modified trimethylolpropane tri(meth) acrylate, isocyanuric acid tris(propylene methoxyethyl) ester, dipentaerythritol penta (meth) acrylate, propionic acid Dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa(meth) acrylate, caprolactone modified dipentaerythritol Alcohol hexa(meth) acrylate or the like.

The acrylate-based prepolymer in the component (β) is not particularly limited as long as it is a polymer or oligomer having photocurability by (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, etc.

Examples of the polyester acrylate-based prepolymer include a prepolymer obtained by a condensation reaction of a polyvalent carboxylic acid and a polyhydric alcohol to obtain a polyester having a hydroxyl group at both terminals of the molecule. a polymer obtained by esterifying the aforementioned hydroxyl group of the obtained polyester oligomer with (meth)acrylic acid; and subjecting the polyvalent carboxylic acid to an alkylene oxide addition reaction to obtain an oligomer, using (meth)acrylic acid The hydroxyl group of the terminal of the obtained oligomer is esterified.

Examples of the epoxy acrylate-based prepolymer include a prepolymer obtained by making a relatively low molecular weight bisphenol type epoxy resin or a novolac type epoxy resin. The oxirane ring is reacted with (meth)acrylic acid for esterification.

As the urethane-based prepolymer, for example, a prepolymer obtained by reacting a polyether polyol or a polyester polyol with a polyisocyanate to obtain a polyamino group can be exemplified. An acid ester oligomer, which is obtained by esterifying the obtained polyurethane oligomer with (meth)acrylic acid.

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

In the component (β), the polyfunctional acrylate monomer and the acrylate prepolymer may each be one type or two or more types.

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

[solvent]

The coating composition preferably further contains a solvent in addition to the component (α) and the component (β). By coating the composition containing a solvent, as described later, the coating composition can be more easily applied and dried to 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. , butanol, 1-methoxy-2-propanol and other alcohols; acetone, methyl ethyl ketone, 2-pentanone, isophorone, cyclohexanone and other ketones; ethyl acetate, butyl acetate and other esters ; cellulite such as 2-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, and a photosensitization, within the scope of the effects of the present invention. Various optional components such as a agent, a polymerization inhibitor, 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, 2-ethylhexyl (meth)acrylate, and dodecyl (meth)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 known photopolymerization initiator which has been conventionally 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 combination An aryl ketone photopolymerization initiator such as a benzophenone dimethyl ketal compound, a benzamidine benzoate compound or an α-mercapto oxime compound; a thioether compound and a thioxanthone A sulfur-containing photopolymerization initiator such as a compound; a fluorenylphosphine oxide compound such as a mercapto diarylphosphine oxide; an anthraquinone compound.

Further, in the case where the coating composition is hardened 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 content of the photocurable component.

(light sensitizer)

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 content of the photocurable component.

(antioxidant, UV absorber, light stabilizer)

The antioxidant, the ultraviolet absorber, and the light stabilizer may be known compounds, but a reaction type antioxidant such as a (meth) acrylonitrile group, a UV absorber, and a light stabilizer are preferably used in the molecule. The antioxidants, ultraviolet absorbers, and light stabilizers are bonded by irradiation of energy lines In the polymer chain, it is possible to inhibit the self-hardening layer from escaping over time, thereby exerting the functions of the components for a long period of time.

The coating composition preferably contains a cerium oxide sol as a component (α), and more preferably a cerium oxide sol having an average particle diameter of 0.03 μm to 0.05 μm containing cerium oxide fine particles 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 present on the surface opposite to the side of the support sheet or in a region in the vicinity thereof, and is more concentrated than the other regions, thereby suppressing the formation of the composite sheet for forming a protective film. The effect of adhesion becomes higher. In the coating layer, in order to polarize the components contained in the cerium oxide sol or the like, the coating conditions of the coating composition may be adjusted.

<<Manufacturing method of coating composition>>

The coating composition can be obtained, for example, by using an energy ray polymerizable compound such as the component (α) and the component (β), and optionally other components other than the energy ray polymerizable compound. The components of the cloth composition are formulated. The coating composition can be obtained, for example, by the same method as the above-described adhesive composition except for the difference in the formulation components.

When a solvent is used, it may be used by mixing a solvent with any of the formulation components other than the solvent to preliminarily dilute the formulation component; or by using the solvent in the following manner, that is, not using the solvent Any of the other ingredients to be mixed is previously diluted to mix the solvent with the ingredients.

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

◎Method for producing a composite sheet for forming a protective film

The composite sheet for forming a protective film of the present invention can be produced by forming a film for forming a protective film using the composition for forming a protective film, forming a coating layer by using the coating composition, and sequentially laminating a coating layer. , a support sheet and a film for forming a protective film. In the case where the support sheet is composed of a plurality of layers, it is only necessary to laminate the plurality of layers to form a support sheet. For example, when the support sheet is formed by laminating a substrate and an adhesive, an adhesive layer may be formed using the above-described adhesive composition.

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. In addition, when the respective layers are formed of the composition, the surface of the layer adjacent to the protective film may be directly formed on the surface of the layer, or a release film (release sheet) may be separately used for the release film (release sheet). The surface is formed on the surface, and the formed layer is bonded to the surface of the layer adjacent to the composite sheet for forming a protective film. However, in order to suppress the occurrence of voids between the coating layer and the uneven surface (back surface) of the support sheet, it is preferred to apply a coating composition directly to the uneven surface of the support sheet to form a coating layer.

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

The coating layer is preferably formed by coating a coating composition on the uneven surface of the support sheet (the back surface 10b of the support sheet 10 in FIGS. 1 and 2, that is, the back surface 11b of the substrate 11). The material is allowed to dry and the formed coating film is hardened as needed.

The coating composition may be applied to the target surface by a known method, and examples thereof include the following various coating machines: an air knife coater, a knife coater, a bar coater, and a gravure coater. Roll coater, roll coater, curtain coater, die coater, knife coater, screen coater, wire bar coater, contact coater, etc. .

In the case where the coating composition is applied to the uneven surface of the support sheet, it is preferable to prevent the occurrence of voids between the coating layer and the uneven surface of the support sheet. By suppressing the generation of the above-mentioned void portion, it is possible to suppress diffused reflection of light at the boundary between the coating layer and the uneven surface of the support sheet, and it is possible to perform laser printing on the surface of the protective film more clearly.

In order to suppress the occurrence of the above-described void portion, for example, it is preferred to use a coating composition having a small viscosity. 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, but the coating composition is preferably subjected to heat drying. In this case, for example, drying is preferably carried out at 70 ° C to 130 ° C for 0.5 minutes to 5 minutes.

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

In the case of hardening by irradiation of an energy ray, for example, when irradiating ultraviolet rays, a high-pressure mercury lamp, a fused H-type lamp, a xenon lamp, a black lamp, or an LED lamp is used as an ultraviolet source, and the irradiation amount is preferably set to 100 mJ/ It is sufficient to irradiate at a temperature of ² to 500 mJ/cm ² . On the other hand, when an electron beam is irradiated, an electron beam is generated by an electron beam accelerator or the like, and irradiation is preferably performed at 150 kV to 350 kV. Among them, it is preferred to form a coating by irradiating ultraviolet rays.

When the support sheet is formed by laminating a substrate and an adhesive, for example, the adhesive layer can be directly applied to the surface of the coated substrate (the surface 11a of the substrate 11 in FIGS. 1 and 2). Formed from the composition of the agent. However, it is generally preferred to employ a method in which an adhesive layer is separately formed in advance and the adhesive layer is bonded to the surface of the substrate: for example, the adhesive composition is applied to the release-treated surface of the release sheet and dried. Thereby, an adhesive layer is formed, the formed adhesive layer is bonded to the surface of the substrate, and the release sheet is removed or the like.

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, which is advantageous Crosslinking by heating can also be carried out together with drying. The heating conditions can be, for example, 100 ° C to 130 ° C and 1 minute to 5 minutes, but are not limited thereto.

In the case where the support sheet is composed of a single layer (single layer) such as a substrate, and, for example, any of the case where the support sheet is composed of a substrate and an adhesive layer, and the like, The surface of the coated support sheet (the surface 10a of the support sheet 10 in FIG. 1 and FIG. 2, that is, the surface 12a of the adhesive layer 12) is directly coated with a composition for forming a protective film to form a film for forming a protective film. However, in the same manner as in the case of the above-mentioned adhesive layer, the film for forming a protective film is separately formed, and the film for forming a protective film is bonded to the surface of the support sheet: peeling treatment of the release sheet The film for protective film formation is applied to the surface and dried to form a film for forming a protective film, and the formed film for forming a protective film is bonded to the surface of the support sheet, and the release sheet is removed as necessary.

The composition for forming a protective film is applied to the target surface 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 drying can be carried out by the same method as in the case of applying 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 method. For example, a composite sheet for forming a protective film can be produced by forming an adhesive layer using the above-described adhesive composition, and using After the protective film forming composition is formed into a film for forming a protective film, the adhesive layer and the film for forming a protective film are laminated to form a laminate, and the surface of the adhesive layer of the laminate (the adhesive layer is not The surface of the substrate on which the coating film is formed is bonded to the surface of the substrate having the coating layer (the surface 11a of the substrate 11 in FIGS. 1 and 2).

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

For example, in the case of producing a composite sheet for forming a protective film as shown in FIG. 1 , when the composite sheet for forming a protective film is viewed from above, the surface area of the film for forming a protective film is smaller than the surface area of the adhesive layer. In the case of the above-mentioned manufacturing method, the film for forming a protective film which has been previously cut into a predetermined size and shape may be provided on the adhesive layer.

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

The method of using the composite sheet for forming a protective film of the present invention 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, first, 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.

Then, the film for forming a protective film is cured by heating to form a protective film. A back grinding tape is attached to the surface (electrode forming surface) of the semiconductor wafer In this case, the back grinding tape is usually removed from the semiconductor wafer to form a protective film.

Then, the semiconductor wafer is diced to form a semiconductor wafer. During the formation of the protective film to the dicing, the protective film may be irradiated with laser light from the coating side of the composite sheet for forming a protective film to print the surface of the protective film. In this case, as described above, the surface roughness Ra of the surface (back surface) on the opposite side to the side in contact with the support sheet in the coating layer is sufficiently small, and the aforementioned back surface of the coating layer is a smooth surface or a degree of unevenness. Suppressed. Therefore, when the laser light is irradiated, it is possible to suppress the diffuse reflection of the laser light on the aforementioned back surface of the coating layer, so that the protective film can be clearly subjected to laser printing.

In addition, the semiconductor wafer obtained by cutting the semiconductor wafer before dicing or dicing may be from the back surface of the semiconductor wafer or the semiconductor wafer (the surface of the composite sheet for forming a protective film) by an infrared camera or the like. Observe and thereby check the status. For example, when it is a semiconductor wafer, the semiconductor wafer may be detected to be damaged by a chip or a crack.

On the other hand, in the semiconductor wafer with a protective film of the present invention, as described above, the surface roughness Ra of the surface (back surface) on the opposite side to the side in contact with the support sheet in the coating layer is sufficiently small, and is further suppressed. A gap is formed between the coating and the uneven surface (back surface) of the support sheet. Therefore, when the semiconductor wafer or the semiconductor wafer is observed through the protective film forming composite sheet from the coating side by an infrared camera or the like, a clear detection image can be obtained, and thus the detection can be performed with high precision.

Then, from the support sheet, the semiconductor wafer is peeled off together with the protective film attached to the back surface of the semiconductor wafer, and the semiconductor wafer with the protective film is obtained. For example, when the support sheet is formed by laminating a substrate and an adhesive, and the adhesive layer is energy ray-curable, the adhesive layer is cured by irradiation of the energy ray, and the adhesive layer is cured. The semiconductor wafer is picked up together with a protective film attached to the back surface of the semiconductor wafer, whereby the semiconductor wafer with the protective film is more easily obtained.

For example, when the composite sheet 1 for protective film formation shown in FIG. 1 is used, the protective film forming film 13 of the protective film forming composite sheet 1 is attached to the back surface of the semiconductor wafer, and the exposed supporting sheet 10 is exposed. (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. Then, after the protective film forming film 13 is cured to form a protective film, the protective film is subjected to laser printing, followed by cutting, and the adhesive layer 12 is attached to the above treatment by irradiating the energy ray as necessary. The region other than the portion is hardened, and then the semiconductor wafer with the protective film is picked up. When the adhesive layer 12 is an energy ray-curable composite film 1 for forming a protective film, it is necessary to prevent the protective film forming composite sheet 1 from being peeled off from the jig and not to make the adhesive layer 12 specific. The mode of zone hardening is adjusted. 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 structure for attaching the composite sheet 1 for forming a protective film to the jig.

On the other hand, when the composite sheet 2 for protective film formation shown in FIG. 2 is used, the back surface of the semiconductor wafer is attached to the film 23 for protective film formation of the composite sheet 2 for protective film formation, and the jig is used for the jig. The adhesive layer 16 is attached to a cutting jig (not shown) such as a ring frame to fix the protective film forming composite sheet 2 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 cutting, and the adhesive layer 12 is hardened by irradiating the energy ray as necessary, and then the protective film is picked up. The semiconductor wafer can be used. 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 harden a specific region of the adhesive layer 12. The way to adjust. On the other hand, unlike the composite sheet 1 for forming a protective film, the composite sheet 2 for forming a protective film must have the adhesive layer 16 for a jig. By having the adhesive layer 16 for the jig, the adhesive layer 12 can be selected in a wide range of compositions 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, in the same manner as in the case where the film for forming a protective film is thermosetting, the film for protective film formation of the composite sheet for forming a protective film is attached to the back surface of the semiconductor wafer, and the composite film for forming a protective film is formed. The sheet is fixed to the cutting device.

Then, the film for forming a protective film is cured by irradiation of an energy ray to form a protective film. Attached to the surface of the semiconductor wafer (electrode forming surface) In the case of a belt, the back grinding belt is usually removed from the semiconductor wafer to form a protective film.

Then, the semiconductor wafer is diced to form a semiconductor wafer. During the formation of the protective film to the dicing, the protective film may be irradiated with laser light from the coating side of the composite sheet for forming a protective film to print the surface of the protective film. The process from the printing to the cutting can be performed in the same manner as in the case where the film for forming a protective film is thermosetting. In the same manner as this case, the protective film can be clearly subjected to laser printing by an infrared camera. The detection is performed with high precision.

Then, from the support sheet, the semiconductor wafer is peeled off together with the protective film attached to the back surface of the semiconductor wafer, and the semiconductor wafer with the protective film is obtained.

This method is particularly preferably used in the case where a support sheet is laminated with a substrate and an adhesive, and the adhesive layer is a non-energy-curable composite sheet 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, and then the semiconductor wafer is diced and the semiconductor wafer with the protective film is picked up, the adhesive layer is non-energy hardened. In the case of the property, the film for forming a protective film can be hardened by irradiating the energy ray at any stage before the semiconductor wafer is picked up.

For example, a support sheet is formed by laminating a substrate and an adhesive, and In the case where the pressure-sensitive adhesive layer is an energy ray-curable composite film for forming a protective film, the method described below is preferred.

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

Then, the protective film is irradiated with laser light from the coating side of the composite sheet for forming a protective film, and the surface of the protective film is printed to further cut the semiconductor wafer to form a semiconductor wafer. The process from the printing to the cutting can be performed in the same manner as in the case where the film for forming a protective film is thermosetting. In the same manner as this case, the protective film can be clearly subjected to laser printing by an infrared camera. The detection is performed with high precision.

Then, the protective film forming film is cured by irradiation of the energy ray to form a protective film, and the adhesive layer is cured, and the semiconductor wafer and the back surface of the semiconductor wafer are protected from the cured adhesive layer. The films are picked up together, thereby obtaining a semiconductor wafer with a protective film.

On the other hand, in the case of winding a long composite film for forming a protective film, a state in which a release film (a release film 15 in FIGS. 1 and 2) is laminated on the exposed surface of the film for forming a protective film is usually used. 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 1 for forming a protective film shown in FIG. 1 and the composite sheet 2 for forming a protective film shown in FIG. 2). The composite sheet for forming a protective film is taken up into a roll shape, and a coating layer, a support sheet, and a protective film shape are sequentially laminated. The buildup units of the film for forming and the release film are sequentially laminated in the radial direction of the roll. As a result, the laminated units which are in contact with each other in the radial direction of the roll become the surface of the release film of one build-up unit (the surface opposite to the side on which the film for forming a protective film is provided), and the other laminated unit The back surface of the coating layer (the surface opposite to the side in contact with the substrate) is in contact with and pressed, and the roll of the composite sheet for forming a protective film is directly stored in this state. However, by providing a coating layer, adhesion of the release film and the coating layer between the buildup units can be suppressed, and thus the adhesion of the composite sheet for forming a protective film of the present invention can be suppressed.

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 the film for a protective film is provided on the film for forming a protective film is superimposed so that the total thickness of the coating layer is in the same direction and the total thickness of the coating layer is 10 μm to 60 μm. A plurality of sheets were formed, and a laminate having one outermost layer as a coating layer and the other outermost layer as a release film was formed, and 980.665 mN (that is, 100 gf was applied in the lamination direction of the composite sheet for forming a protective film. After the state of the force (external force) is allowed to stand at 40 ° C for 3 days, the release film closest to the coating of the outermost layer in the lamination direction is at a peeling speed of 300 mm/min and a peeling angle of 180°. And peeling off from the adjacent coating (the coating closest to the coating of the outermost layer in the laminating direction), and the peeling force at this time is preferably 10 mN/50 mm or less, more preferably 7.5 mN/50 mm or less. It is 5mN/50mm or less. In addition, all the composite sheets for forming a protective film which are superimposed here have the same structure. Further, the number of sheets of the composite sheet for forming a protective film to be laminated is preferably 10 sheets. The protective film formation of the present invention can be confirmed based on the peeling force of such a release film. The adhesion of the composite sheet is used to suppress the efficacy (blocking resistance).

[Examples]

Hereinafter, the present invention will be described in more detail by way of specific examples. However, the present 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 further prepared to obtain a protective film-forming composition (III-1) having a solid content 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 (weight average molecular weight: 400,000, glass transition temperature - 1 ° C) 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: a dicyclopentadiene type epoxy resin ("Epiclon HP-7200HH" manufactured by DIC Corporation, epoxy equivalent of 274 g/eq to 286 g/eq) of 30 parts by mass.

‧Hot hardener (B2)

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

(hardening accelerator (C))

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

(filling material (D))

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

(coupler (E))

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

(colorant (I))

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

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

The protective film-forming composition (III-1) obtained above was applied onto the release-treated surface of the first release film ("SP-P502010*" manufactured by Lintec Co., Ltd., thickness: 50 μm) 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, on the surface opposite to the surface on which the first release film was provided, the release film 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. A long laminated body in which the first release film, the protective film formation film, and the second release film are sequentially laminated is obtained. Then, after the laminate is wound into a long roll, the laminated material was cut to a width direction of the laminate of the protective film is formed at the symbol w denotes a width of a composite sheet ₁₁ (shown in Figure 3 of the The direction is 300mm.

Then, the second release film and the film for forming a protective film are drawn from the second release film side in the center portion in the width direction of the laminate in a circular shape having a diameter of 220 mm in plan view. The method performs a half cut of the cut into the slit. In addition, the "top view" of the laminated body in this specification means that the laminated body is seen from the upper direction of the laminated direction of the laminated body. Then, the second release film and the film for forming a protective film are removed from the laminate so that the circular portion formed by the half-cut is left, and the film is sequentially formed on the release surface of the first release film. The first laminate in which the film for forming a protective film and the second release film are formed in a plan view. Circular protective film of the first laminate film is formed corresponding to the protective film 3 is formed as shown in FIG. ₁ 220mm film 13 is formed of a circular sheet composite protective film in a diameter d.

(Preparation of coating composition)

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

(formation of coating)

Then, a polypropylene substrate (thickness 100 μm) having a surface roughness Ra of 0.4 μm on the uneven surface and a surface roughness Ra of 0.02 μm on the surface opposite to the uneven surface was used. The above-mentioned uneven surface of the melting point of 140 ° C to 160 ° C is applied to the coating composition obtained above, and after drying at 80 ° C for 1 minute, ultraviolet rays are irradiated with a light amount of about 230 mJ/cm ^{2 to} harden the dried coating film. A coating (thickness 3 μm) was formed.

(Preparation of adhesive composition)

100 parts by mass of an alkyl (meth) acrylate copolymer and 10 parts by mass (solid content) of an aromatic polyisocyanate compound (crosslinking agent, "Takenate D110N" manufactured by Mitsui Chemicals, Inc.), and further blending methyl groups Ethyl ketone, an adhesive composition (iii) having a solid content concentration of 30% by mass was obtained.

The (meth)acrylic acid alkyl ester copolymer is 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 to obtain a weight average molecular weight of 600,000. Acrylic resin.

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

A third release film made of polyethylene terephthalate film having a thickness of 38 μm by a knife coating machine and a release process by forming a polyoxynitride-based release agent layer on one side (Lintec Co., Ltd.) The peeling-treated surface of "SP-PET381031C") was coated with the obtained adhesive composition (iii) and dried to form an adhesive layer (thickness: 5 μm).

Then, after the surface of the substrate on which the coating layer is formed on the opposite side to the uneven surface is subjected to corona treatment, the adhesive layer is bonded to the corona-treated surface to obtain a coating layer, a substrate, and an adhesive. The layer and the third release film are sequentially laminated and include a second laminate of the support sheet.

Then, the second laminated body is taken up into a roll, and the second laminated body is cut into the width direction of the second laminated body (the composite sheet 1 for forming a protective film shown in FIG. 3 is symbolized). w ₁ indicates the direction of the width) is 300 mm in size.

(Manufacture of composite sheet for forming a protective film)

The second laminate film was removed from the first laminate obtained as described above, and the circular protective film formation film was exposed. Moreover, the 3rd release film was removed from the 2nd laminated body obtained above, and the adhesive layer was exposed. Then, the exposed surface of the film for forming a protective film is bonded to the exposed surface of the adhesive layer, thereby obtaining a film corresponding to the coating layer, the substrate, the adhesive layer, the protective film, and the first release film. The third laminate of the composite sheet for forming a protective film is laminated.

With respect to the third layered body obtained as described above, half of the slits were cut out from the coating side, and all of the coating layer, the base material, and the adhesive layer were drawn in a circular shape having a diameter of 270 mm in plan view. In the half-cut, the circle having a diameter of 270 mm in plan view is concentric with respect to a circle having a diameter of 220 mm formed by the film for forming a protective film, and a slit is cut out from all of the coating layer, the substrate, and the adhesive layer.

Then, in the plan view, a circle having a diameter of 270 mm is drawn in the width direction of the third layered product at a position 20 mm apart from the radially outer side of the circle (the composite sheet for forming a protective film shown in FIG. 3). In the case of 1 in the direction of the width indicated by the symbol w ₁ ), one half of the coating, the substrate and the adhesive layer are cut in half from the coating side. A curved peripheral portion of the adhesive layer indicated by reference numeral 121 in the composite sheet for forming a protective film shown in FIG. 3 is formed in a slit corresponding to the pair of circular arcs. Further, the distance (20 mm) between the circle having a diameter of 270 mm and the arc is equivalent to the symbol w ₂ in the composite sheet 1 for forming a protective film shown in Fig. 3 .

In the longitudinal direction of the third layered product (the direction orthogonal to the direction indicated by the symbol w ₁ in the composite sheet 1 for protective film formation shown in FIG. 3), the drawing is performed 2 The concentric circle and the half cut of a pair of arcs are used to draw two straight lines connecting the arcs in the longitudinal direction between adjacent portions in a plan view, from the coating side, to the coating layer, All of the material and the adhesive layer were cut and cut in half. 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 for forming a protective film shown in Fig. 3 .

Then, the coating, the substrate, and the adhesive layer in the portion between the circle having a diameter of 270 mm and the pair of arcs and the two straight lines connecting the arcs are connected in plan view In addition, the composite sheet for forming a protective film shown in FIGS. 1 and 3 was obtained. 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 d ₂ of 270 mm in Fig. 3 . In addition, 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, the surface roughness Ra of the uneven surface was 1 μm. In the same manner as in Example 1, except that the substrate was not 0.4 μm, a composite sheet for forming a protective film was obtained.

[Example 3]

As shown in Table 1, the surface roughness Ra of the uneven surface was 1 μm instead of 0.4 μm, and the thickness of the coating layer was set to 1 μm instead of 3 μm, and the same method as in Example 1 was used. A composite sheet for forming a protective film was obtained.

[Example 4]

In the same manner as in Example 1, except that the thickness of the coating layer was changed to 1 μm instead of 3 μm, a composite sheet for forming a protective film was obtained.

[Example 5]

As shown in Table 1, the substrate having the surface roughness Ra of the uneven surface was 1 μm instead of 0.4 μm, and the thickness of the coating layer was set to 6 μm instead of 3 μm, and the same method as in Example 1 was used. 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 3 μm instead of 0.4 μm, and the thickness of the coating layer was set to 6 μm instead of 3 μm, and the same method as in Example 1 was used. Obtained A composite sheet for forming a protective film is obtained.

[Comparative Example 1]

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

[Comparative Example 2]

As shown in Table 1, the base material was placed such that the uneven surface faced the opposite side, that is, the adhesive layer side (inside), and no coating layer was formed (that is, the conventional configuration shown in Fig. 5). In the same manner as in Example 1, a composite sheet for forming a protective film was obtained.

[Comparative Example 3]

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

[Comparative Example 4]

The same amount of spherical cerium oxide ("SC2050MA" manufactured by Admatechs Co., Ltd., average particle size 0.5 μm), which was surface-modified with an epoxy group, was used instead of the cerium oxide sol. A coating composition was prepared in the same manner as in Example 1 except that the dispersion was dispersed 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.

In 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 the adhesive layer was attached using an attachment device ("RAD-2700F/12" manufactured by Lintec Co., Ltd.). The film for protective film formation was attached to the back surface of the crucible wafer (outer diameter 8 吋, thickness 100 μm) heated to 70 ° C in a ring frame made of stainless steel.

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 Corporation), 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, as follows. The two patterns (pattern 1, pattern 2) were subjected to laser printing on the protective film.

(pattern)

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

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

Then, the characters formed on the protective film by the above-described laser printing were evaluated for visibility from the substrate side (laser printing property) in accordance with the following criteria. The results are shown in Table 1.

(evaluation benchmark)

A: All the characters of the pattern 1 and the pattern 2 are clear, and the characters of the pattern 1 and the pattern 2 can be read without any problem.

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 one of the characters 1 and 2 is unclear.

[Adhesion resistance (1)]

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

Then, with respect to the composite sheet for forming a protective film of Examples 1 to 6 and Comparative Example 4, it was attempted to roll up a coating layer, a substrate, an adhesive layer, a film for forming a protective film, and a first release film. 10 parts of the buildup unit, for the composite film for forming a protective film of Comparative Example 1 to Comparative Example 3, When a coating layer is present, it is attempted to roll out 10 layers of a laminate unit in which a substrate, an adhesive layer, a film for forming a protective film, and a first release film are sequentially laminated, and in this case, a protective film for forming a contact with each other during winding is evaluated. The contact portions of the composite sheets were adhered to each other, and the degree of adhesion in the case of adhesion was evaluated in accordance with the following criteria. The results are shown in Table 1.

(evaluation benchmark)

A: Adhesion of the aforementioned contact portions to each other was not confirmed at all.

B: It was confirmed that the contact portions were slightly adhered to each other, but the composite sheet for forming a protective film could be wound out without any problem.

C: When the contact portions are completely adhered to each other, and the composite sheet for forming a protective film is wound up, 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 out so as to have a width of 50 mm and a length of 100 mm. Further, at the time of cutting, the longitudinal direction of the tape was made to coincide with the application direction of the adhesive composition.

Ten pieces of the tape thus obtained were prepared, and the tapes were laminated to prepare test pieces. At this time, in the case of the first to sixth embodiments and the comparative example 4, the belt was 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. Then, the test piece is sandwiched between two glass plates (width: 75 mm, length: 15 mm, thickness: 5 mm), and the laminate of the glass plates and the test piece is placed on the predetermined portion as a lowermost layer with a glass plate as a whole, and One of the most The test piece is pressurized by placing a plumb bob on the upper glass plate. At this time, the force applied to the test piece in the lamination direction of the belt was 980.665 mN (that is, 100 gf). In this state, the laminate of the glass plate and the test piece was stored in a wet 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 of the lowermost layer (the first release film which is in contact with the glass plate in the lowermost layer) and the film for forming a protective film adjacent to the first release film are removed. And attaching the exposed adhesive layer to the support plate via the double-sided adhesive tape, thereby removing only the first lower release film from the test piece and adjacent to the first release film after the heating and pressurization promotion test The test piece obtained by the film for protective film formation is fixed to the said support board.

Then, in the case of the first embodiment to the sixth embodiment and the comparative example 4, the coating, the substrate, the adhesive layer, and the film for forming a protective film of the uppermost layer which is the furthest from the support plate in the above-mentioned fixing body. The laminated material of the structure was removed, and the exposed first peeling film was peeled off from the adjacent coating layer at a peeling speed of 300 mm/min and a peeling angle of 180° using a tensile tester, 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 is the furthest from the support plate in the above-mentioned fixing member is removed, and the laminate is removed. In the tensile tester, the exposed first release film was peeled off from the adjacent substrate 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 measured value of the peeling force of the first release film thus obtained was used as an index of the blocking resistance of the composite sheet for forming a protective film.

In the case where the peeling force of the first release film to be measured is sufficiently small, the test piece is taken out from the moist heat promoter, and the first release film of the lowermost layer is removed from the test piece as described above. When the film for forming a protective film adjacent to the first release film that is in contact with the glass plate is removed, the first release film to be subjected to the measurement of the peeling force is first from the layer adjacent to the first release film (in the embodiment). In the case of 1 to 6 and Comparative Example 4, the coating layer was used, and in the case of Comparative Example 1 to Comparative Example 3, the substrate was peeled off. In this case, the test piece is taken out from the moist heat promoter, and after removing the first release film of the lowermost layer from the test piece, the film for forming a protective film adjacent to the first release film is not removed, and the protective film is removed. The film for formation is bonded to the support plate via a double-sided adhesive tape, whereby the test piece obtained by removing only the first release film of the lowermost layer from the test piece is fixed to the support plate, and the fixed object is the same as described above. The peeling force of the first release film was measured.

The results are shown in Table 1.

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

With respect to the composite sheets for forming a protective film of Examples 1 to 6 and Comparative Example 4 obtained above, a contact surface roughness meter ("SURFTEST SV-3000" manufactured by Mitutoyo Co., Ltd.) was used, and the critical value λc was set to 0.8. In mm, the evaluation length Ln was set to 4 mm, and the outermost surface of the substrate side, that is, the surface roughness Ra of the surface on the opposite side to the substrate side in the coating layer was measured in accordance with JIS B0601:2001. The results are shown in Table 1. In the composite sheet for forming a protective film of Comparative Example 1 to Comparative Example 3, the surface roughness Ra of the surface opposite to the side of the adhesive layer of the base material is described as the substrate side. Surface roughness Ra of the surface.

[Gloss value of the surface of the coating]

The composite sheet for forming a protective film of Examples 1 to 6 and Comparative Example 4 obtained above was a self-coating layer according to JIS K 7105 using a gloss meter (Gloss meter "VG 2000" manufactured by Nippon Denshoku Co., Ltd.). On the side opposite to the substrate side, the 20° specular gloss of the surface of the coating was measured, and the measured value was taken as the gloss value of the surface of the coating. The results are shown in Table 1.

[Measurement value of haze from the coated side]

With respect to the composite sheets for forming a protective film of Examples 1 to 6 and Comparative Example 4 obtained as described above, a self-coating layer was used according to JIS K 7136 using a fog meter ("NDH-2000" manufactured by Nippon Denshoku Industries Co., Ltd.). The haze was measured on the side. The results are shown in Table 1.

The composite sheet for forming a protective film of Examples 1 to 6 is provided with a coating on the outermost layer on the substrate side, and has excellent laser printing properties and blocking resistance.

In particular, the composite sheet for forming a protective film of the first embodiment, the second embodiment, the fourth embodiment, and the fifth embodiment has excellent laser printing properties as compared with the composite sheet for forming a protective film of the third embodiment and the sixth embodiment. In the composite sheets for forming a protective film of the first, second, fourth, and fifth embodiments, "the thickness of the coating layer (μm)] / [the surface roughness of the uneven surface of the substrate] The value of Ra(μm)]" is larger, and the relative thickness of the surface roughness Ra of the coating surface with respect to the uneven surface of the substrate is thicker, whereby the outermost surface of the substrate side (the side opposite to the substrate side in the coating layer) The surface roughness Ra (μm) of the surface is smaller.

Further, the composite sheets for forming a protective film of Examples 1 to 4 are excellent in blocking resistance as compared with the composite sheets for forming a protective film of Examples 5 and 6, and it is presumed that Example 1 to The thickness of the coating layer of the composite sheet for forming a protective film of Example 4 was thin.

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 the composite sheet for forming a protective film shown in FIG. 4, the composite sheet for forming a protective film of Comparative Example 1 has adhesion to the substrate. The surface (surface) on the side of the agent layer is a surface on the opposite side (back surface) which is an uneven surface, and does not have a coating layer. Therefore, although the adhesion resistance is excellent, the laser printing property is inferior.

In the composite sheet for forming a protective film of Comparative Example 2, similarly to the composite sheet for forming a protective film shown in FIG. 5, the surface (back surface) on the side opposite to the surface (surface) on the side of the substrate having the adhesive layer is It has a smooth surface and does not have a coating, so that although the laser printing property is good, the blocking resistance is poor. The composite sheet for forming a protective film of Comparative Example 3 also has the same configuration as the composite sheet for forming a protective film of Comparative Example 2, but has poor adhesion resistance and poor laser printing properties. The reason is that the surface (surface) on the side of the base material having the adhesive layer is an uneven surface, and the surface roughness Ra of the uneven surface is larger than the surface roughness Ra of the composite sheet for forming a protective film of Comparative Example 2. It is estimated that in 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 of the surface of the protective film is larger than that of Comparative Example 2, whereby the diffuse reflection of light Larger, laser printing is even worse. Further, it is estimated that the composite sheet for forming a protective film of Comparative Example 2 and Comparative Example 3 has a void portion between the uneven surface of the substrate and the adhesive layer, but Comparative Example 3 has a concave-convex surface as compared with Comparative Example 2. Since the surface roughness Ra is large, the void portion is increased. Therefore, in Comparative Example 3, the diffuse reflection of light is larger than that of Comparative Example 2, and the laser printing property 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 having the adhesive layer was uneven as in the composite sheet for forming a protective film of Example 1. Surface, and also has a coating, resistant Excellent adhesion, but poor printability. It is presumed that in the composite sheet for forming a protective film of Comparative Example 4, the outermost surface of the substrate side (the surface on the opposite side to the substrate side in the coating layer) is compared with the side of the substrate having the adhesive layer. The surface (surface) is the surface (back surface) on the opposite side, and the surface roughness Ra (μm) is large.

(industry availability)

The present invention can be used to manufacture a semiconductor wafer or the like whose back surface is protected by a protective film.

1‧‧‧Composite film for protective film formation

10‧‧‧Support tablets

10a‧‧‧Surface of the support sheet

10b‧‧‧Back of 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

14a‧‧‧Coated surface

14b‧‧‧The back of the coating

15‧‧‧Release film

15a‧‧‧ peeling film surface

Claims (5)

A composite sheet for forming a protective film, comprising a support sheet, and a film for forming a protective film on one surface of the support sheet, on a surface opposite to a side of the support sheet having the film for forming a protective film Providing a coating layer; a surface roughness (Ra) of a surface of the coating layer opposite to a side in contact with the support sheet is smaller than a surface roughness (Ra) of a surface of the support sheet having the side of the coating layer . The composite sheet for forming a protective film according to the above aspect of the invention, wherein the release sheet having the release film is further provided on the film for forming a protective film, and the peeling force of the release film measured by the following method is 10mN/50mm or less; the method for measuring the peeling force of the release film is to provide the composite film for forming a protective film having a width of the release film of 50 mm and a length of 100 mm on the film for forming a protective film, wherein all of the coating layers are oriented in the same direction and A plurality of sheets are stacked so as to have a total thickness of the coating layer of 10 μm to 60 μm, whereby a laminate in which one outermost layer is a coating layer and the other outermost layer is a release film is formed, and the laminated body is used for forming the protective film. The state in which the force of 980.665 mN was applied in the lamination direction of the composite sheet was allowed to stand at 40 ° C for 3 days, and the peeling film closest to the coating of the outermost layer in the laminating direction was peeled at a peeling speed of 300 mm/min. The peeling force at this time was measured by peeling off from the adjacent coating under the condition of 180°. The composite sheet for forming a protective film according to claim 1 or 2, 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 layer or a non-energetic 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 layer of thermosetting or an energy ray-curable layer.