TWI805704B - Composite sheet for forming protective film and method for manufacturing semiconductor chip with protective film - Google Patents

Abstract

A composite sheet for forming a protective film including a support sheet having a substrate and an energy ray-curable protective film-forming film provided on the support sheet, wherein the substrate has a property that a loss tangent (tangδ) at -15℃ is 0.05 or more and a storage modulus (G’) at 80℃ is 35.0 MPa or more.

Description

Composite sheet for forming protective film and method of manufacturing semiconductor wafer with protective film

The present invention relates to a method for manufacturing a composite sheet for forming a protective film and a semiconductor wafer with a protective film. This application claims priority based on Japanese Patent Application No. 2018-043567 for which it applied in Japan on March 9, 2018, and uses the content here.

In recent years, semiconductor devices have been manufactured by applying a so-called face down packaging method. In the flip-chip method, a semiconductor wafer having electrodes such as bumps on the circuit surface is used, and the electrodes are bonded to the substrate. Therefore, the back surface of the semiconductor wafer which is the side opposite to the circuit surface is exposed.

In some cases, a resin film containing an organic material is formed on the back surface of the exposed semiconductor wafer as a protective film, and the semiconductor wafer with the protective film is housed in a semiconductor device. The protective film is used to prevent cracks from occurring on the semiconductor wafer after the dicing step and packaging.

In order to form such a protective film, for example, a composite sheet for forming a protective film provided with a film for forming a protective film for forming a protective film on a support sheet having a base material is used, for example. In the composite sheet for forming a protective film, the protective film can be formed by hardening the film for forming a protective film, and the support sheet can be used as a dicing sheet and can be used as a product that integrates the film for forming a protective film and the dicing sheet .

As such a composite sheet for protective film formation, what is provided with the thermosetting protective film formation film which forms a protective film by heat hardening is utilized. For example, after attaching the protective film forming composite sheet to the back surface of the semiconductor wafer (the surface opposite to the electrode forming surface) with a thermosetting protective film forming film, the protective film forming film is cured by heating and become a protective film, and the semiconductor wafer is divided into semiconductor wafers together with the protective film by dicing. And in the state which attached this protective film to a semiconductor wafer, it peeled and picked up from a support sheet. In addition, curing and dicing of the thin film for protective film formation may be performed in the reverse order.

As a method of dividing a semiconductor wafer together with a protective film, a method of dicing a semiconductor wafer using a dicing blade is widely used. In contrast, in recent years, various methods of dividing a semiconductor wafer without using a dicing blade have been studied. For example, it is known to form a modified layer inside a semiconductor wafer by irradiating laser light so as to focus on a focal point set inside the semiconductor wafer. The semiconductor wafer of the resin film is spread in the plane direction of the resin film together with the resin film, the resin film is cut, and the semiconductor wafer is divided into pieces at the position of the modified layer to obtain the semiconductor wafer. In order to spread the resin film in the planar direction, the semiconductor wafer is divided well together with the resin film. For example, cold stretching at a low temperature of -15° C. has been considered.

The method of dividing by cold expansion is different from the method of using a dicing blade. In the semiconductor wafer, there is no cutting portion caused by the dicing blade, and more semiconductor wafers can be obtained from the semiconductor wafer, and it has the advantage of not generating cutting chips. advantage. As a thing for die-bonding a semiconductor wafer to the circuit formation surface of a substrate, there is a film-like adhesive. When using this film-like adhesive in the past, the above-mentioned dividing method mainly uses the above-mentioned resin film (refer to Patent Document 1 ,2).

Therefore, when the above-mentioned method of dividing by cold expansion as described above can be applied to a semiconductor wafer having a protective film of a thermosetting protective film forming film or a cured product thereof, as a semiconductor wafer provided with a protective film The method of manufacturing semiconductor wafers, the usefulness of this method is very high. prior art literature patent documents

[Patent Document 1] Japanese Unexamined Patent Publication No. 2012-222002 [Patent Document 2] Japanese Patent Laid-Open No. 2017-183705

However, in the production process of semiconductor wafers, for semiconductor wafers with a protective film of a thermosetting protective film forming film or a hardened product, it is intended to apply the method disclosed in Patent Documents 1 and 2 under the low temperature condition of -15°C. In the method of splitting by cold stretching, there is a problem of cracking of the support sheet, and when cold stretching is carried out at a normal temperature of 15~25°C, the protective film of the thermosetting protective film forming film and its cured product may split bad possibility. In addition, in the heating and hardening step of the thin film for forming a thermosetting protective film, the semiconductor wafer or the semiconductor wafer on which the semiconductor wafer is placed is diced on the wafer attaching part on the composite sheet for forming a protective film around which is supported by a ring frame. After the laminated body of the semiconductor wafer is placed in a state where a plurality of the semiconductor wafers are left still with a slight gap therebetween, the film for forming a thermosetting protective film is heated and hardened together with the support sheet. When the base material of PE (polyethylene) with excellent cold resistance is used as the support sheet, when the thermosetting protective film forming film is heated and hardened, the PE base support sheet is bent and a single sheet of protective film forming compound is formed. The problem that the wafer attaching part of the sheet is in contact with the semiconductor wafer or the semiconductor wafer on another protective film forming composite sheet accommodated below.

Therefore, the object of the present invention is to provide a composite sheet for forming a protective film, and a method of manufacturing a semiconductor wafer with a protective film and a semiconductor device using the composite sheet. In the method of splitting by cold expansion, when a semiconductor wafer with a protective film is manufactured using a film for forming a thermosetting protective film, the support sheet will not be broken due to cold expansion, and the film for forming a thermosetting protective film will not be broken. Under the condition of heating and hardening, the support sheet does not bend.

In order to solve the above-mentioned problems, the inventors of the present invention, as a result of intensive research, found that among the composite sheets for protective film formation, when the dynamic viscoelasticity of the base material of the support sheet is measured by using The storage elastic modulus (G') of any one is more than a predetermined value, and the said object can be achieved.

That is, the present invention is as follows. [1] A composite sheet for forming a protective film comprising a thermosetting film for forming a protective film on a support sheet having a base material, wherein the loss positive contact (tan δ) at -15°C is measured when the dynamic viscoelasticity of the base material is measured It is 0.05 or more and the storage elastic modulus (G') at 80° C. is 35.0 MPa or more. [2] The composite sheet for forming a protective film as described in [1] above, wherein the base material is cut out so that the MD direction or the CD direction becomes the long side direction, and the long side is 110mm x the short side is 22mm, and the measured distance before heating is When L ₀ becomes about 100 mm and heated at 130° C. for 2 hours under a load of 2.2 g, and then allowed to cool and measure the distance between measurements L ₁ after heating at 23° C., the MD direction of the above-mentioned substrate is taken as When cutting the long side and when cutting the CD direction of the above-mentioned base material as the long side, either the thermal expansion rate X represented by the formula (1) is -3% or more and +3% or less, X=[( L ₁ -L ₀ )/L ₀ ]×100...(1). [3] The composite sheet for forming a protective film according to the above [1] or [2], wherein the support sheet has a base material and an adhesive layer, and the base material, the adhesive layer, and the protective film are sequentially laminated. The film is formed by laminating thin films.

[4] The composite sheet for forming a protective film according to the above [3], wherein the adhesive layer is non-energy ray curable or energy ray curable.

[5] The composite sheet for forming a protective film according to [3] or [4] above, wherein the adhesive layer has a thickness of 3 to 20 μm.

[6] A method of manufacturing a semiconductor wafer with a protective film, comprising the following steps: laminating the semiconductor wafer on the composite sheet for forming a protective film as described in any one of the aforementioned items [1] to [5] The step of forming a laminate on the side of the aforementioned thermosetting protective film forming film; the step of irradiating the inside of the semiconductor wafer with laser light to form a modified layer inside the semiconductor wafer; A step of heating and hardening to form a protective film; and a step of cold-expanding the laminate at a temperature lower than normal temperature to divide the semiconductor wafer and the protective film forming film or protective film.

That is, the present invention includes the following aspects.

[1'] A composite sheet for forming a protective film, comprising a support sheet having a substrate; and a thermosetting protective film forming film provided on the support sheet, the substrate having a loss positive connection at -15°C (tanδ) is 0.05 or more and the storage elastic modulus (G') at 80°C is 35.0 MPa or more.

[2'] The composite sheet for forming a protective film according to claim 1, wherein the substrate has a long side of 110mm x a short side of 22mm cut out so that the MD direction or CD direction of the aforementioned substrate becomes the long side direction, and When the distance between measurements L ₀ before heating becomes about 100 mm, heat at 130° C. for 2 hours under a load of 2.2 g, and then let cool to measure the distance L ₁ between measurements after heating at 23° C. Either when the MD direction of the aforementioned base material is taken as the long side or when the CD direction of the aforementioned base material is taken as the long side, the thermal expansion ratio X represented by the following formula (1) is -3% or more and +3% or less, X=[(L ₁ -L ₀ )/L ₀ ]×100…(1). [3'] The composite sheet for forming a protective film as described in [1'] or [2'], wherein the support sheet further comprises sequentially laminating the adhesive layer, the base material, the adhesive layer, and the thermosetting The protective film is formed by laminating thin films. [4'] The composite sheet for forming a protective film according to [3'], wherein the adhesive layer is non-energy ray curable or energy ray curable. [5'] The composite sheet for forming a protective film according to [3'] or [4'], wherein the adhesive layer has a thickness of 3 to 20 μm. [6'] A method of manufacturing a semiconductor wafer with a protective film, comprising the following steps: laminating the semiconductor wafer on the protective film forming device described in any one of items [1'] to [5'] The side of the aforementioned thermosetting protective film forming thin film of the composite sheet is used to manufacture a laminate; the inside of the aforementioned semiconductor wafer of the aforementioned laminate is irradiated with laser light to form a modified layer inside the aforementioned semiconductor wafer; the aforementioned laminate is The aforementioned thin film for forming a thermosetting protective film is heated and cured to form a protective film; The aforementioned protective film is divided.

According to the present invention, it is possible to provide a composite sheet for forming a protective film, and a method for manufacturing a semiconductor wafer with a protective film and a semiconductor device using the same, and the composite sheet for forming a protective film is applied by cold expansion at a temperature lower than normal temperature. And when the method of dividing and using the thin film for forming a thermosetting protective film to manufacture a semiconductor wafer with a protective film, the base material of the support sheet will not be cracked due to cold expansion, and even if the film for forming a thermosetting protective film Under the condition of heating and hardening of the film, the supporting sheet will not bend.

form for carrying out the invention

◎Composite sheet for protective film formation The composite sheet for forming a protective film of the present invention comprises a support sheet having a substrate; and a thermosetting protective film forming film provided on the support sheet, the substrate having a loss positive connection (tanδ) at -15°C A composite sheet for forming a protective film having a storage elastic modulus (G') of 0.05 or more and a storage elastic modulus (G') at 80°C of 35.0 MPa or more.

In the composite sheet for forming a protective film of the present invention, the loss positive connection (tan δ) of the base material contained in the support sheet at -15°C is 0.05 or more, so that the cold resistance of the base material becomes good and does not suffer from a temperature lower than 0.05. The support sheet is cracked due to cold expansion at room temperature, and the storage elastic modulus (G') at 80°C is 35.0 MPa or more, even under the condition of heating and hardening the film for forming a thermosetting protective film , the support sheet will not bend, and in the state where a plurality of sheets are left still with a small gap in the box, even if the thermosetting protective film forming film is heated and hardened, it can prevent one piece of protective film forming film from being bent. The wafer attaching part of the composite sheet is in contact with a semiconductor wafer or a semiconductor wafer accommodated on another protective film forming composite sheet below.

In the composite sheet for forming a protective film of the present invention, the long side 110 mm x short side 22 mm are cut out in such a manner that the MD direction (that is, the flow direction) or the CD direction (that is, the width direction) of the above-mentioned base material becomes the long side direction. When heating at 130°C for 2 hours under a load of 2.2 g in such a way that the distance between measurements L ₀ becomes about 100 mm, and then letting it cool and measuring the distance between measurements after heating at 23° C. as L ₁ , the above-mentioned base Either when cutting the MD direction of the material as the long side or when cutting the CD direction of the above-mentioned base material as the long side, the thermal expansion ratio X represented by the formula (1) is -3% or more and +3% The following is preferred. X=(L ₁ -L ₀ )/L ₀ ×100…(1)

When the thermal expansion ratio X is -3% or more and +3% or less, even under the condition of heating and curing the thermosetting protective film forming film, the bending of the support sheet becomes small, and by making the above-mentioned base material Either when the MD direction is taken as the long side or when the CD direction of the above-mentioned base material is taken as the long side, the thermal expansion ratio X is -3% or more and +3% or less. Under the condition that the thin film for film formation is heated and hardened, the support sheet does not bend extremely in a specific direction. As an aspect, the thermal expansion ratio X is preferably 0-2.2% or less.

In addition, in this specification, the term "thin film for forming a thermosetting protective film" means a thing before thermosetting, and the term "protective film" means a thing after curing a thin film for forming a thermosetting protective film.

In addition, in this specification, even after thermosetting of the thermosetting protective film forming film, as long as the laminated structure of the hardened product of the support sheet and the thermosetting protective film forming film (in other words, the support sheet and the protective film) can be maintained, This laminated structure is called "composite sheet for protective film formation".

In this specification, "normal temperature" means a temperature that is not cooled or heated, that is, a normal temperature, for example, a temperature of 15 to 25° C. is mentioned. The so-called "cold expansion" refers to applying an expansion force in a direction parallel to the surface of the semiconductor wafer at a temperature lower than normal temperature (eg -30~5°C).

Fig. 1 is a cross-sectional view schematically showing an embodiment of the composite sheet for forming a protective film of the present invention. The composite sheet 1 for forming a protective film shown here includes a thermosetting protective film forming film 13 on one surface 10 a of a support sheet 10 . Moreover, the support sheet 10 is a laminate of a base material 11 and an adhesive layer 12. An adhesive layer 12 is provided on one surface 11a of the base material 11 and a thermosetting protective film is provided on the adhesive layer 12. film13. Moreover, the composite sheet 1 for protective film formation is further equipped with the release film 15 on the film 13 for thermosetting protective film formation, and the release film 15 is removed when the composite sheet 1 for protective film formation is used. The thin film 13 for thermosetting protective film formation becomes a protective film by thermosetting.

In the composite sheet 1 for forming a protective film, the adhesive layer 12 is laminated on the aforementioned surface 11a of the substrate 11, and the thermosetting protective film forming film 13 is laminated on the surface 12a of the adhesive layer 12 (that is, The surface in contact with the substrate 11 of the adhesive layer 12 is part of the surface on the opposite side). In addition, among the surface 12a of the adhesive layer 12, the exposed surface on which the film 13 for forming a thermosetting protective film is not laminated, and the surface 13a of the film 13 for forming a thermosetting protective film (the upper surface and the side surface, that is, the surface 13a on which the thermosetting film is formed). A peeling film 15 is laminated on the surface of the film 13 for forming a protective film 13 which is not in contact with the adhesive layer 12 .

The supporting sheet of the above-mentioned composite sheet for forming a protective film is preferably transparent to laser light. The side of the sheet is irradiated with laser light to perform laser printing through the supporting sheet.

In addition, in the process of manufacturing a semiconductor wafer with a protective film, the support sheet should be transparent to laser light, and the semiconductor wafer can be irradiated with laser light in the infrared region from the side of the support sheet (sometimes called SD). Furthermore, the modified layer can be formed inside the semiconductor wafer via the support sheet.

Furthermore, the support sheet is transparent to the laser light during infrared inspection, and the film for forming the thermosetting protective film is preferably colored. By cold-expanding the semiconductor wafer (sometimes called CE), the When the semiconductor wafer is divided and individualized using the above-mentioned modified layer formation site as a starting point, it is possible to easily check whether the thermosetting protective film forming film or protective film can be cut reliably, and when the infrared inspection is performed, the The state of the semiconductor wafer can be easily inspected by emitting light through the support sheet, and it is possible to suppress a decrease in the manufacturing efficiency of the semiconductor device. Thereby, whether the thin film for thermosetting protective film formation or a protective film can be cut|disconnected reliably, and a state can be checked easily, and the manufacturing efficiency reduction of a semiconductor device can be suppressed.

Fig. 2 is a cross-sectional view schematically showing another embodiment of the composite sheet for forming a protective film of the present invention. In addition, in FIG. 2 , the same elements as in FIG. 1 are shown, and the same symbols as in FIG. 1 are attached, and detailed description thereof is omitted. The same applies to the figures after the second figure. In the composite sheet 2 for protective film shape shown here, the thermosetting protective film forming film 23 is laminated on the entire surface 12a of the adhesive layer 12, and the adhesive layer 16 for jigs is laminated on the thermosetting adhesive layer 12a. A part of the surface 23a of the film 23 for forming a thermosetting protective film (that is, the surface of the film 23 for forming a thermosetting protective film that is opposite to the surface in contact with the adhesive layer 12), the surface of the film 23 for forming a thermosetting protective film 23a, on the exposed surface where the adhesive layer 16 for the jig is not laminated, and the surface 16a of the adhesive layer 16 for the jig (the upper surface and the side surface, that is, the resistance of the adhesive layer 16 for the jig to the thermosetting property). The upper surface and the side surface in contact with the protective film forming film 23) are laminated with the release film 15, and are the same as the protective film forming composite sheet 1 shown in FIG. 1 except for the above points.

The protective film forming composite sheet 2 shown in FIG. 2 is in a state where the peeling film 15 is removed and the back surface of the semiconductor wafer (not shown) is attached to the surface 23a of the thermosetting protective film forming film 23, and A jig such as a ring frame is attached to the surface 16a of the adhesive layer 16 for the jig and used.

The composite sheet for forming a protective film of the present invention is not limited to what is shown in Figures 1 to 2, and part of the composition of what is shown in Figures 1 to 2 may be changed or changed within the range that does not impair the effects of the present invention It can be eliminated, and other components can be further added to what has been explained in the past.

The aforementioned thin film for forming a thermosetting protective film is cured by heating to become a protective film. This protective film is for protecting the semiconductor wafer or the back surface (the surface opposite to the electrode formation surface) of the semiconductor wafer. The film for forming a thermosetting protective film is soft and can be easily attached to an object to be attached. For example, the tensile elastic modulus (Younger's modulus) of the film for forming a thermosetting protective film is about 1×10 ⁶ to 1×10 ⁸ Pa. On the other hand, the tensile elastic modulus (Younger's modulus) of the protective film obtained by heating and curing becomes hard and is about 1×10 ⁸ to 5.4×10 ⁹ pa.

In the method of manufacturing a semiconductor wafer with a protective film described later, the composite sheet for forming a protective film of the present invention is attached to a semiconductor wafer and used to prepare a support sheet and a film for forming a thermosetting protective film in this order. And laminated bodies made of semiconductor wafers. Hereinafter, each structure of the composite sheet for protective film formation of this invention is demonstrated in detail.

○Support sheet The support sheet is not particularly limited as long as it has a base material and can be provided with the film for forming the thermosetting protective film. Tasks such as surface cutting sheets. Preferable examples of the above-mentioned support sheet include those composed only of base materials commonly used in the field of semiconductor wafer processing sheets, and those obtained by laminating a base material and an adhesive layer. The supporting sheet of the composite sheet for forming a protective film of the present invention may be a sheet composed only of the base material in one aspect, or may include the base material and the supporting sheet provided on the aforementioned base material in another aspect. Sheet of adhesive layer.

The support sheet may be composed of one layer (single layer), or may be composed of multiple layers of two or more layers. When the support sheet is composed of plural layers, these plural layers may be the same as or different from each other. That is, all the layers may be the same, all the layers may be different, or only a part of the layers may be the same. Furthermore, when 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, which means that at least one of the material and thickness of each layer is different from each other.

The thickness of the support sheet may be appropriately selected according to the purpose, depending on whether sufficient flexibility can be imparted to the above-mentioned composite sheet for forming a protective film, adhesion to a semiconductor wafer, and workability at the time of manufacturing the composite sheet for forming a protective film. 10-500 μm is good, 20-350 μm is more preferred, and 30-200 μm is particularly preferred. Here, the "thickness of the support sheet" means the total thickness of the layers constituting the support sheet. The total value of the layer thickness. Moreover, the support sheet can be a concave-convex surface on at least one surface. When the support sheet includes a convex portion on the concave-convex surface, the thickness of the support sheet can be calculated by setting the front end of the convex portion as a common point. . In addition, in this specification, "thickness" means a value measured using a constant pressure thickness measuring device.

Based on the above reasons, the support sheet is preferably transparent. However, it may be opaque, and may be colored according to the purpose, as long as the transmittance of a predetermined laser wavelength is ensured and the checkability of cutting can be ensured.

Specifically, the transmittance of light with a wavelength of 532 nm on the support sheet is preferably above 30%, preferably above 50%, and especially preferably above 70%. When the light transmittance is in such a range, when the thermosetting protective film-forming film or protective film is irradiated with laser light through the support sheet and printed on, relatively clear printing can be achieved. On the other hand, the upper limit of the transmittance of light with a wavelength of 532 nm on the support sheet is not particularly limited, and can be set to, for example, 95%. As an example, the transmittance of light with a wavelength of 532nm on the support sheet is preferably not less than 30% and not more than 95%, more preferably not less than 50% and not more than 95%, and more preferably not less than 70% and not more than 95%. .

In addition, the transmittance of light with a wavelength of 1064nm on the support plate is preferably at least 30%, more preferably at least 50%, and particularly preferably at least 70%. When the transmittance of the aforementioned light is in such a range, when the semiconductor wafer is irradiated with laser light (SD) in the infrared region from the side of the support sheet, the laser light in the infrared region can pass through the support sheet and be well placed inside the semiconductor wafer. The modified layer is formed, and when the thermosetting protective film-forming thin film or protective film is irradiated with laser light through the support sheet to perform printing, relatively clear printing can be achieved. On the other hand, the upper limit of the transmittance of light with a wavelength of 1064 nm on the support sheet is not particularly limited, for example, it is set at 95%. As an example, the transmittance of light with a wavelength of 1064nm on the support sheet is preferably 30% to 95%, preferably 50% to 95%, and particularly preferably 70% to 95%. . Next, each layer constituting the support sheet will be described in more detail.

‧Substrate The aforementioned base material is in the form of a sheet or a film. As its constituent material, a polymer with excellent cold resistance whose loss positive connection (tan δ) at -15°C is 0.05 or more is selected, and the storage elastic modulus at 80°C ( G') is a polymer having excellent heat resistance of 35.0 MPa or more. For example, as a polymer with excellent heat resistance, it is considered to be so-called relatively hard, and a polymer with a high Tg (ie, glass transition temperature) is considered to be good, and as a polymer with excellent cold resistance, it is considered to be so-called soft. A polymer with a low Tg is good, but, for example, low elongation at break is not acceptable even if the Tg is low in terms of cold resistance in cold expansion. It is not easy to select a single polymer that satisfies both cold resistance and heat resistance. In addition, the direct loss (tan δ) at -15°C and the storage elastic modulus (G') at 80°C of the present invention can be obtained using the method described in <Dynamic Viscoelasticity Measurement> below. The positive loss (tan δ) at -15°C is preferably not less than 0.05 and not more than 0.13, more preferably not less than 0.06 and not more than 0.09. The storage elastic modulus (G') at 80°C is preferably not less than 35.0 MPa and not more than 180 MPa, more preferably not less than 60 MPa and not more than 150 MPa. As an aspect, the base material of the protective film forming composite sheet of the present invention has a positive loss (tan δ) at -15°C of preferably 0.05 to 0.13, preferably 0.06 to 0.09, and at 80°C The storage elastic modulus (G') is preferably not less than 35.0 MPa and not more than 180 MPa, preferably not less than 60 MPa and not more than 150 MPa.

As a constituent material of the base material that satisfies both cold resistance and heat resistance with a loss direct (tanδ) of 0.05 or more at -15°C and a storage elastic modulus (G') of 35.0 MPa or more at 80°C, It is made by adding soft ingredients such as low Tg resins for imparting cold resistance to various heat-resistant resins (such as polybutylene terephthalate containing soft ingredients); added to various heat-resistant resins for A rubber component that imparts cold resistance and is modified (such as an olefin-based thermoplastic elastomer (TPO)); and a heat-resistant resin layer and a cold-resistant resin layer are laminated to form two or three layers layers etc. As the heat-resistant resin, the storage elastic modulus (G') at 80°C should be 35.0 MPa or more, and polypropylene (sometimes abbreviated as PP), polybutylene terephthalate (sometimes abbreviated as PP) can be mentioned. for the case of PBT), etc. As a cold-resistant resin, it is enough to have a loss positive connection (tan δ) of 0.05 or more at -15°C, and examples include low-density polyethylene (sometimes abbreviated as LDPE), linear low-density polyethylene (sometimes abbreviated as In the case of LLDPE), high-density polyethylene (in the case of abbreviated as HDPE) and other polyethylenes (in the case of abbreviated as PE), etc.

In addition, examples of resins that can be used as base materials for resins having cold resistance include polyolefins other than polyethylene such as polybutene, polybutadiene, polymethylpentene, and norbornene resins. ; Ethylene-based copolymers such as ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylate copolymer, ethylene-norbornene copolymer (that is, use ethylene as a unit chlorinated vinyl resins such as polyvinyl chloride and vinyl chloride copolymers (that is, resins obtained by using vinyl chloride as a monomer); polystyrene; polycycloolefins; Ethylene formate, polyethylene naphthalate, polyethylene isophthalate, polyethylene-2,6-naphthalene dicarboxylate, fully aromatic compounds with all structural units being aromatic ring groups Polyesters such as polyesters; copolymers of two or more of the foregoing polyesters; poly(meth)acrylates; polyurethanes; polyurethane acrylates; polyimides; polyamides; polycarbonates; fluororesins; polycondensates Aldehyde; modified polyphenylene ether; polyphenylene sulfide; polysulfide; polyether ketone, etc.

In addition, in this specification, "(meth)acrylic acid" is used as a concept including both "acrylic acid" and "methacrylic acid". The same applies to terms similar to (meth)acrylic acid.

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

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

The base material may be composed of one layer (single layer), or may be composed of multiple layers of two or more layers. When composed of multiple layers, the multiple layers may be the same as or different from each other. The combination of the plural layers is not particularly limited. When the base material is composed of a plurality of layers, the total thickness of each layer may be the above-mentioned preferable base material thickness.

When there is an adhesive layer on the substrate, the surface roughness Ra of the surface of the substrate with the adhesive layer (sometimes referred to as the substrate surface) is preferably 0.001~0.1μm, and 0.005~0.08μm is more appropriate Best, especially 0.01~0.04μm. When the said surface roughness Ra of a base material surface is below the said upper limit, laser printing can be performed relatively clearly on a protective film. The aforementioned surface roughness Ra of the substrate surface can be adjusted by, for example, molding conditions of the substrate, surface treatment conditions, and the like.

As a method of individualizing a semiconductor wafer into semiconductor wafers, it is possible to irradiate laser light in the infrared region and form a modified layer inside the semiconductor wafer in such a manner as to focus on the focal point set inside the semiconductor wafer. A method of dividing a semiconductor wafer into individual pieces by applying force to the semiconductor wafer and starting from the location where the modified layer is formed. When the aforementioned surface roughness Ra of the base material surface is, for example, 0.01 to 0.2 μm, the composite sheet for forming a protective film with such a base material is suitable for forming a modified layer inside the above-mentioned semiconductor wafer to separate the semiconductor wafer into pieces used when.

On the other hand, the surface roughness Ra of the surface (back surface) of the substrate opposite to the surface (surface) provided with the adhesive layer, in other words, is the surface roughness Ra of the support sheet provided with the film for forming a thermosetting protective film. (Surface) The surface roughness Ra of the opposite side (sometimes referred to as the back of the substrate) is preferably 0.001~4μm, more preferably 0.005~3.7μm, more preferably 0.01~3.4μm, Especially preferably 0.02~3.1μm. By making the aforementioned surface roughness Ra of the backside of the substrate below the aforementioned upper limit, it is possible to more easily reduce the surface roughness Ra of the surface on the opposite side to the side in contact with the support sheet. When irradiated with laser light (SD) in the infrared region, the laser light in the infrared region can pass through the support sheet to form a modified layer well inside the semiconductor wafer, and it is easier to perform laser printing on the protective film clearly. The aforementioned surface roughness Ra of the back surface of the base material can be adjusted by, for example, molding conditions of the base material, surface treatment conditions, and the like.

The resin of the material of the base material may also be cross-linked. In addition, the resin of the material of the base material may be formed by extruding a thermoplastic resin and formed into sheets, or may be formed by stretching, or may be cured by a known method. Thinned and hardened by means of means and thinned. In addition, the base material may be colored or printed.

It is preferable that the base material contains polypropylene in terms of having excellent heat resistance and appropriate flexibility, and having good cold expansion suitability and pick-up suitability. The base material containing polypropylene, for example, may be a single-layer or multiple-layer base material composed of polypropylene alone, or may be a multiple-layer base material composed of a polypropylene layer and a resin layer other than polypropylene. Substrate. Also, as an aspect, the base material of the protective film forming composite sheet of the present invention is a thin sheet made of polybutylene terephthalate containing a soft component, made of polypropylene (PP) and olefin-based thermal A three-layer transparent film composed of a plastic elastomer (sometimes abbreviated as TPO) mixed resin, or a three-layer transparent film of polyethylene (PE)/polypropylene (PP)/polyethylene (PE) is preferable. The composite sheet for forming a protective film of the present invention has heat resistance through the base material, and can effectively suppress the bending of the support sheet even under the conditions of heat-curing the thermosetting protective film-forming film.

It is preferable that the base material has high accuracy of thickness, that is, one that can suppress variation in thickness regardless of the location. Among the above-mentioned constituent materials. Examples of materials that can be used to constitute such a substrate with high thickness accuracy include polyethylene, polyolefins other than polyethylene, polyethylene terephthalate, ethylene-vinyl acetate copolymer, and the like.

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

The optical properties of the base material may satisfy the optical properties of the supporting sheet described above. That is, the base material may be transparent or opaque, may be colored according to the purpose, and may be vapor-deposited with other layers.

In order to improve the adhesion with other layers such as the adhesive layer provided on the substrate, the surface may be subjected to sandblasting treatment, embossing treatment by solvent treatment, etc., corona discharge treatment, electron beam irradiation Oxidation treatment such as plasma treatment, ozone‧ultraviolet irradiation treatment, flame treatment, chromic acid treatment, hot air treatment, etc. In addition, the base material may be a surface treated with a primer. In addition, when the base material is stored by laminating the antistatic coating layer and a plurality of protective film-forming composite sheets, it may also have a layer that prevents the base material from sticking to other sheets, and the base material from sticking to the adsorption table. .

Substrates can be fabricated using known methods. For example, a base material containing a resin can be produced by molding a resin composition containing the aforementioned resin.

． adhesive layer The aforementioned adhesive layer is in the form of a sheet or film and contains an adhesive. Examples of the adhesives include acrylic resins, urethane resins, rubber resins, silicone resins, epoxy resins, polyvinyl ethers, polycarbonates, ester resins, and the like. Adhesive resin, preferably acrylic resin.

In addition, in the present invention, the so-called "adhesive resin" is a concept including both an adhesive resin and an adhesive resin. Resins that exhibit adhesiveness due to other ingredients such as heat or water, and resins that exhibit adhesiveness due to the presence of triggers such as heat or water.

The adhesive layer may be composed of one layer (single layer), or may be composed of multiple layers of two or more layers. When composed of multiple layers, the multiple layers may be the same or different from each other and The combination of these plural layers is not particularly limited.

The thickness of the adhesive layer is preferably 1-100 μm, more preferably 1-60 μm, more preferably 1-30 μm, and particularly preferably 3-20 μm. Here, the "thickness of the adhesive layer" means the thickness of the entire adhesive layer, for example, the thickness of an adhesive layer composed of a plurality of layers means the total thickness of all the layers constituting the adhesive layer.

The optical properties of the adhesive layer should only satisfy the optical properties of the supporting sheet described above. That is, the adhesive layer may be transparent or opaque, and may be colored according to the purpose.

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

In the present invention, the term "energy ray" means something having energy quanta among electromagnetic waves or charged particle rays, and examples thereof include ultraviolet rays, radiation rays, electron rays, and the like. The ultraviolet system can be irradiated by using, for example, a high-pressure mercury lamp, a fusion lamp, a xenon lamp, a black light, an LED lamp, or the like as an ultraviolet source. Electron beams can be produced by electron beam accelerators and the like by irradiation. In the present invention, "energy ray curability" means the property of being cured by irradiation of energy ray, and "non-energy ray curability" means the property of not being cured even when irradiated with energy ray.

＜Adhesive composition＞ For the adhesive layer system, an adhesive composition having an adhesive can be used. For example, the adhesive layer can be formed at the target site by applying the adhesive composition on the surface to be formed of the adhesive layer and drying it as necessary. A more specific method of forming the adhesive layer will be described in detail later together with methods of forming other layers. In the adhesive composition, the content ratio of the components that do not vaporize at normal temperature is usually the same as the content ratio of the above-mentioned components in the adhesive layer. In addition, in the present specification, "normal temperature" means a temperature that is not cooled or heated, that is, a normal temperature, for example, a temperature of 15 to 25° C. is mentioned.

The coating of the adhesive composition may be carried out using a known method, for example, the use of an air knife coater, a blade coater, a bar coater, a gravure coater, a roll coater, Various coater methods such as roll knife coater, curtain coater, die coater, knife coater, screen coater, wire rod coater, lick roll coater, etc. .

The drying conditions of the adhesive composition are not particularly limited. When the adhesive composition contains the solvent described later, it is preferable to dry it by heating. Best to dry.

When the adhesive layer is energy ray curable, as an adhesive composition containing an energy ray curable adhesive, that is, an energy ray curable adhesive composition, for example, a non-energy ray curable adhesive resin (I- 1a) (Hereinafter, it may be abbreviated as "adhesive resin (I-1a)") and an adhesive composition (I-1) of an energy ray-curable compound; energy ray-curable resin containing an unsaturated group Adhesion in which a permanent adhesive resin (I-2a) is introduced into the side chain of a non-energy ray-curable adhesive resin (I-1a) (hereinafter, abbreviated as "adhesive resin (I-2a)") an adhesive composition (I-2); and an adhesive composition (I-3) containing the aforementioned adhesive resin (I-2a) and an energy ray-curable compound; and the like.

＜Adhesive composition (I-1)＞ The above-mentioned adhesive composition (I-1) contains a non-energy ray-curable adhesive resin (I-1a) and an energy ray-curable compound as described above.

[Adhesive resin (I-1a)] The aforementioned adhesive resin (I-1a) is preferably an acrylic resin. As said acrylic resin, the acrylic polymer which has the structural unit derived from an alkyl (meth)acrylate at least is mentioned, for example. The structural unit which the said acrylic resin has may be only 1 type, and may be 2 or more types, and when there are 2 or more types, the combination and ratio of these can be arbitrarily selected.

Examples of the alkyl (meth)acrylate include those in which the alkyl group constituting the alkyl ester has 1 to 20 carbon atoms, and the alkyl group is preferably linear or branched. As the alkyl (meth)acrylate, more specifically, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, Butyl (meth)acrylate, isobutyl (meth)acrylate, second-butyl (meth)acrylate, third-butyl (meth)acrylate, amyl (meth)acrylate, (meth) Hexyl acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate , isononyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, lauryl (meth)acrylate (also known as lauryl (meth)acrylate), (meth)acrylate base) tridecyl acrylate, tetradecyl (meth)acrylate (also known as myristyl (meth)acrylate), pentadecyl (meth)acrylate, cetyl (meth)acrylate ((meth)acrylate ) palmityl acrylate (also known as), heptadecyl (meth)acrylate, octadecyl (meth)acrylate (also known as stearate (meth)acrylate), nonadecyl (meth)acrylate, Eicosyl (meth)acrylate, etc.

In terms of improving the adhesion of the adhesive layer, the acrylic polymer preferably has a structural unit derived from an alkyl (meth)acrylate having 4 or more carbon atoms derived from the alkyl group. Moreover, in terms of further enhancing the adhesion of the adhesive layer, the carbon number of the aforementioned alkyl group is preferably 4-12, more preferably 4-8. Also, the alkyl (meth)acrylate having an alkyl group having 4 or more carbon atoms is preferably an alkyl acrylate.

The acrylic polymer preferably further has a structural unit derived from a functional group-containing monomer in addition to a structural unit derived from an alkyl (meth)acrylate. As the above-mentioned functional group-containing monomer, for example, the above-mentioned functional group can be used as a starting point of crosslinking by reacting with the cross-linking agent described later, or the above-mentioned functional group can be obtained by reacting with the compound containing no unsaturated group described later. A thing capable of introducing an unsaturated group into a side chain of an acrylic polymer by reacting an unsaturated group.

As said functional group in a functional group containing monomer, a hydroxyl group, a carboxyl group, an amino group, an epoxy group etc. are mentioned, for example. That is, as a functional group containing monomer, a hydroxyl group containing monomer, a carboxyl group containing monomer, an amino group containing monomer, an epoxy group containing monomer etc. are mentioned, for example.

Examples of the hydroxyl group-containing monomer include hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxy (meth)acrylate, - Hydroxyalkyl (meth)acrylates such as hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate; vinyl alcohol , non-(meth)acrylic unsaturated alcohols such as allyl alcohols (unsaturated alcohols not having a (meth)acryl group skeleton), and the like.

As the aforementioned carboxyl group-containing monomers, for example, ethylenically unsaturated monocarboxylic acids (that is, monocarboxylic acids having ethylenically unsaturated bonds) such as (meth)acrylic acid and crotonic acid; fumaric acid , itaconic acid, maleic acid, citraconic acid and other ethylenically unsaturated dicarboxylic acids (that is, dicarboxylic acids having ethylenically unsaturated bonds); anhydrides of the aforementioned ethylenically unsaturated dicarboxylic acids; Carboxyalkyl (meth)acrylate, such as 2-carboxyethyl acrylate, etc.

The functional group-containing monomer system is preferably a hydroxyl-containing monomer or a carboxyl-containing monomer, and preferably a hydroxyl-containing monomer.

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

In the aforementioned acrylic polymer, the content of the structural unit derived from the functional group-containing monomer is preferably 1-35% by mass, more preferably 2-32% by mass, relative to the total amount (total mass) of the structural unit. Preferably, 3-30% by mass is especially preferred.

The above-mentioned acrylic polymer system may further have a structural unit derived from another monomer in addition to the structural unit derived from an alkyl (meth)acrylate and the structural unit derived from a functional group-containing monomer. The aforementioned other monomers are not particularly limited as long as they can be copolymerized with an alkyl (meth)acrylate or the like. Examples of the aforementioned other monomers include styrene, α-methylstyrene, vinyl toluene, vinyl formate, vinyl acetate, acrylonitrile, acrylamide, and the like.

The said other monomer which comprises the said acrylic polymer may be only 1 type, and may be 2 or more types, and when there are 2 or more types, the combination and ratio of these can be arbitrarily selected.

The aforementioned acrylic polymer can be used as the aforementioned non-energy ray-curable adhesive resin (I-1a). On the other hand, the functional group in the aforementioned acrylic polymer reacts an unsaturated group-containing compound having an energy ray polymerizable unsaturated group (energy ray polymerizable group), which can be used as the energy ray polymer. Line-hardening adhesive resin (I-2a).

The adhesive resin (I-1a) contained in the adhesive composition (I-1) may be only 1 type, or may be 2 or more types, and when 2 or more types are used, the combination and ratio of these can be arbitrarily selected.

In the adhesive composition (I-1), the content of the adhesive resin (I-1a) is relative to the total mass of the adhesive composition (I-1), preferably 5-99% by mass, preferably 10-95% by mass. The mass % is more preferable, and 15-90 mass % is especially preferable.

[Energy Beam Curing Compound] Examples of the energy ray-curable compound contained in the adhesive composition (I-1) include monomers or oligomers that have an energy ray polymerizable unsaturated group and are curable by irradiation with energy ray. Among the energy ray-curable compounds, examples of monomers include trimethylolpropane tri(meth)acrylate, neopentylthritol (meth)acrylate, neopentylitol tetra(methyl) Acrylic esters, dipentylthritol hexa(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol (meth)acrylate, etc. ) acrylate; urethane (meth)acrylate; polyester (meth)acrylate; polyether (meth)acrylate; epoxy (meth)acrylate, etc. Among the energy ray-curable compounds, examples of the oligomers include oligomers obtained by polymerizing the monomers exemplified above, and the like. In terms of large molecular weight and not easy to reduce the storage elastic modulus of the adhesive layer, the energy ray curable compound is based on urethane (meth)acrylate, urethane (meth)acrylate oligomer Things are better.

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

In the aforementioned adhesive composition (I-1), the content of the aforementioned energy ray-curable compound is preferably 1 to 95% by mass, preferably 5 to 90% by mass, relative to the total mass of the aforementioned adhesive composition (I-1). The mass % is more preferable, and 10-85 mass % is especially preferable.

[Crosslinking agent] As the adhesive resin (I-1a), when the aforementioned acrylic polymer having a structural unit derived from a functional group-containing monomer is used in addition to a structural unit derived from an alkyl (meth)acrylate, the adhesive combination The substance (I-1) preferably further contains a crosslinking agent.

The said crosslinking agent reacts with the said functional group, and crosslinks adhesive resin (I-1a) mutually, for example. Examples of the cross-linking agent include isocyanate-based cross-linking agents such as toluene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, and adducts of these diisocyanates (that is, those having an isocyanate group). cross-linking agent); epoxy-based cross-linking agents such as ethylene glycol glycidyl ether (that is, cross-linking agents with glycidyl groups); hexa[1-(2-methyl)-aziridine Aziridine-based crosslinking agents such as triphosphatriazine (that is, a crosslinking agent having an aziridine group); metal chelate crosslinking agents such as aluminum chelates (that is, a metal chelate cross-linking agent for material structure); isocyanurate-based cross-linking agent (that is, a cross-linking agent with isocyanuric acid skeleton) and the like. In terms of increasing the cohesive force of the adhesive to increase the cohesive force of the adhesive layer, and in terms of ease of acquisition, the cross-linking agent is preferably an isocyanate-based cross-linking agent.

The crosslinking agent contained in the adhesive composition (I-1) may be 1 type, or may be 2 or more types, and when 2 or more types are used, the combination and ratio of these can be arbitrarily selected.

In the aforementioned adhesive composition (I-1), with respect to 100 parts by mass of the content of the adhesive resin (I-1a), the content of the crosslinking agent is preferably 0.01-50 parts by mass, more preferably 0.1-20 parts by mass. Best, especially preferably 0.3-15 parts by mass.

[Photopolymerization Initiator] The adhesive composition (I-1) may further contain a photopolymerization initiator. The adhesive composition (I-1) containing a photopolymerization initiator fully advances hardening reaction even when irradiated with energy rays of relatively low energy such as ultraviolet rays.

(thioxanthone)等的9-氧硫

化合物；過氧化物化合物；聯乙醯等的二酮化合物；二苯基乙二酮(benzil)；聯苄(dibenzyl)；二苯基酮；2,4-二乙基9-氧硫

；1,2-二苯基甲烷；2-羥基-2-甲基-1-[4-(1-甲基乙烯基)苯基]丙烷；2-氯蒽醌等。 又，作為前述光聚合起始劑，例如，亦能夠使用1-氯蒽醌等的醌化合物；胺等的光敏化劑等。Examples of the aforementioned photopolymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, benzoin Benzoin compounds such as methyl benzoate and benzoin dimethyl ketal; acetophenone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 2,2-dimethyl Acetophenone compounds such as oxy-1,2-diphenylethan-1-one; bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,4,6- Acyl phosphine oxide compounds such as trimethylbenzoyl diphenyl phosphine oxide; thioether compounds such as benzyl phenyl sulfide and tetramethylthiuram monosulfide; 1-hydroxycyclohexyl phenyl ketone α-ketol compounds such as azobisisobutyronitrile; azo compounds such as azobisisobutyronitrile; titanocene compounds such as titanocene; 9-oxysulfur

(thioxanthone) etc. 9-oxosulfur

Compounds; peroxide compounds; diketone compounds such as diacetyl; benzil; dibenzyl; diphenyl ketone; 2,4-diethyl 9-oxysulfur

; 1,2-diphenylmethane; 2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propane; 2-chloroanthraquinone, etc. Moreover, as said photoinitiator, for example, quinone compounds, such as 1-chloroanthraquinone; photosensitizers, such as an amine, etc. can also be used.

The photopolymerization initiator contained in the adhesive composition (I-1) may be 1 type, or may be 2 or more types, and when 2 or more types are used, the combination and ratio of these can be arbitrarily selected.

In the adhesive composition (I-1), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass, preferably 0.03 to 10 parts by mass, based on 100 parts by mass of the content of the aforementioned energy ray-curable compound. Preferably, 0.05 to 5 parts by mass is particularly preferred.

[Other additives] The adhesive composition (I-1) may contain other additives that do not correspond to any of the above-mentioned components within the range that does not impair the effect of the present invention. Examples of the aforementioned other additives include antistatic agents, antioxidants, softeners (plasticizers), fillers (fillers), rust inhibitors, colorants (pigments, dyes), sensitizers, adhesion imparting agents, Conventional additives such as reaction retarders and crosslinking accelerators (catalysts). In addition, the so-called reaction delay agent is, for example, suppressing the unintended exchange of the adhesive composition (I-1) in storage by the action of a catalyst mixed into the adhesive composition (I-1). Linked reaction thing. As a reaction delay agent, for example, a compound that forms a chelate complex by a chelate to a catalyst, and more specifically, a compound having two or more carbonyl groups (-C (=O)-).

The other additive contained in the adhesive composition (I-1) may be only 1 type, or may be 2 or more types, and when 2 or more types are used, the combination and ratio of these can be arbitrarily selected.

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

[solvent] The adhesive composition (I-1) may also contain a solvent. The adhesive composition (I-1) improves the coating suitability to the surface to be coated by containing a solvent.

The aforementioned solvent is preferably an organic solvent, and as the aforementioned organic solvent, for example, ketones such as methyl ethyl ketone and acetone can be enumerated; esters (that is, carboxylate) such as ethyl acetate; Ether; aliphatic hydrocarbons such as cyclohexane and n-hexane; aromatic hydrocarbons such as toluene and xylene; alcohols such as 1-propanol and 2-propanol, etc.

As the above-mentioned solvent, for example, the solvent used in the manufacture of the adhesive resin (I-1a) can also be used directly in the adhesive composition (I-1a) without removing it from the adhesive resin (I-1a). ), and the solvent of the same or different type from the solvent used in the production of the adhesive resin (I-1a) may be additionally added during the production of the adhesive composition (I-1).

The solvent contained in the adhesive composition (I-1) may be 1 type or 2 or more types, and when 2 or more types are used, the combination and ratio of these can be arbitrarily selected.

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

＜Adhesive composition (I-2)＞ The aforementioned adhesive composition (I-2) is, as described above, an energy ray curable adhesive resin (I -2a).

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

The above-mentioned unsaturated group-containing compound is, in addition to the above-mentioned energy ray polymerizable unsaturated group, and has the ability to react with the adhesive resin (I-1a) with the functional group in the adhesive resin (I-1a). Compounds with bonded bases. Examples of the aforementioned energy ray polymerizable unsaturated group include (meth)acryl, vinyl (also called ethenyl), allyl (also called 2-propenyl), etc. base) acryl group is preferred. As the group capable of bonding to the functional group in the adhesive resin (I-1a), for example, an isocyanate group and a glycidyl group capable of bonding to a hydroxyl group or an amine group, and a group capable of bonding to a carboxyl group or an epoxy group can be mentioned. Bonded hydroxyl and amino groups, etc.

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

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

In the adhesive composition (I-2), relative to the total mass of the adhesive composition (I-2), the content of the adhesive resin (I-2a) is preferably 5-99% by mass, and preferably 10-95% by mass. The mass % is more preferable, and 10-90 mass % is especially preferable.

[Crosslinking agent] As the adhesive resin (I-2a), for example, as in the adhesive resin (I-1a), when the aforementioned acrylic polymer having a structural unit derived from a functional group-containing monomer is used, the adhesive combination The substance (I-2) may further contain a crosslinking agent.

Examples of the crosslinking agent in the adhesive composition (I-2) include the same ones as the crosslinking agent in the adhesive composition (I-1). The crosslinking agent contained in the adhesive composition (I-2) may be 1 type or 2 or more types, and when 2 or more types are used, the combination and ratio of these can be arbitrarily selected.

In the aforementioned adhesive composition (I-2), equivalent to 100 parts by mass of the content of the adhesive resin (I-2a), the content of the crosslinking agent is preferably 0.01-50 parts by mass, preferably 0.1-20 parts by mass. Preferably, 0.3 to 15 parts by mass is particularly preferred.

[Photopolymerization Initiator] The adhesive composition (I-2) may further contain a photopolymerization initiator. The adhesive composition (I-2) containing a photoinitiator fully advances hardening reaction even if it irradiates the energy ray of low energy, such as an ultraviolet-ray.

Examples of the photopolymerization initiator in the adhesive composition (I-2) include the same ones as the photopolymerization initiator in the adhesive composition (I-1). The photoinitiator contained in an adhesive composition (I-2) may be only 1 type, and may be 2 or more types, and when there are 2 or more types, the combination and ratio of these can be arbitrarily selected.

In the adhesive composition (I-2), equivalent to 100 parts by mass of the adhesive resin (I-2a), the content of the photopolymerization initiator is preferably 0.01-20 parts by mass, and preferably 0.03-10 parts by mass. More preferably, 0.05 to 5 parts by mass is particularly preferred.

[Other additives] The adhesive composition (I-2) may contain other additives that do not correspond to any of the above-mentioned components within the range that does not impair the effect of the present invention. Examples of the other additives in the adhesive composition (I-2) include the same ones as the other additives in the adhesive composition (I-1). The other additive contained in the adhesive composition (I-2) may be only 1 type, or may be 2 or more types, and when there are 2 or more types, the combination and ratio of these can be arbitrarily selected.

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

[solvent] The adhesive composition (I-2) may contain a solvent for the same purpose as that of the adhesive composition (I-1). Examples of the aforementioned solvent in the adhesive composition (I-2) include the same ones as the solvent in the adhesive composition (I-1). The solvent contained in the adhesive composition (I-2) may be 1 type or 2 or more types, and when 2 or more types are used, the combination and ratio of these can be arbitrarily selected. In the adhesive composition (I-2), the content of the solvent is not particularly limited, and may be adjusted appropriately.

＜Adhesive composition (I-3)＞ The said adhesive composition (I-3) contains the said adhesive resin (I-2a) and an energy ray curable compound as mentioned above.

In the adhesive composition (I-3), relative to the total mass of the adhesive composition (I-3), the content of the adhesive resin (I-2a) is preferably 5-99% by mass, and preferably 10-95% by mass. The mass % is more preferable, and 15-90 mass % is especially preferable.

[Energy Beam Curing Compound] Examples of the energy ray-curable compound contained in the adhesive composition (I-3) include monomers and oligomers that have an energy ray polymerizable unsaturated group and can be cured by irradiation with energy ray; The same thing as the energy ray-curable compound contained in adhesive composition (I-1) is mentioned. The aforementioned energy ray-curable compound contained in the adhesive composition (I-3) may be one type, or two or more types, and in the case of two or more types, such combinations and ratios can be arbitrarily selected.

In the aforementioned adhesive composition (I-3), equivalent to 100 parts by mass of the content of the adhesive resin (I-2a), the content of the aforementioned energy ray-curable compound is preferably 0.01 to 300 parts by mass, preferably 0.03 to 200 parts by mass. Parts by mass are preferred, and 0.05 to 100 parts by mass is particularly preferred.

[Photopolymerization Initiator] The adhesive composition (I-3) may further contain a photopolymerization initiator. The adhesive composition (I-3) containing a photopolymerization initiator fully advances hardening reaction even when irradiated with relatively low-energy energy rays such as ultraviolet rays.

Examples of the photopolymerization initiator in the adhesive composition (I-3) include the same ones as the photopolymerization initiator in the adhesive composition (I-1). The photopolymerization initiator contained in the adhesive composition (I-3) may be 1 type, or may be 2 or more types, and when 2 or more types are used, the combination and ratio of these can be arbitrarily selected.

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

[Other additives] The adhesive composition (I-3) may contain other additives that do not correspond to any of the above-mentioned components within the range that does not impair the effect of the present invention. Examples of the aforementioned other additives include the same ones as the other additives in the adhesive composition (I-1). The other additive contained in the adhesive composition (I-3) may be only 1 type, or may be 2 or more types, and when 2 or more types are used, the combination and ratio of these can be arbitrarily selected.

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

[solvent] The adhesive composition (I-3) is based on the same purpose as that of the adhesive composition (I-1), and may contain a solvent. Examples of the aforementioned solvent in the adhesive composition (I-3) include the same ones as the solvent in the adhesive composition (I-1). The solvent contained in the adhesive composition (I-3) may be only one type, or may be two or more types, and in the case of two or more types, such combinations and ratios can be arbitrarily selected. In the adhesive composition (I-3), the content of the solvent is not particularly limited, and may be adjusted appropriately.

<Adhesive compositions other than adhesive compositions (I-1) to (I-3)> So far, the adhesive composition (I-1), adhesive composition (I-2) and adhesive composition (I-3) have been mainly described, and what has been described in the form of these components, All adhesive compositions other than these three types of adhesive compositions (in this specification, referred to as "adhesive compositions other than adhesive compositions (I-1) to (I-3)") are also can be used in the same way.

Examples of adhesive compositions other than the adhesive compositions (I-1) to (I-3) include non-energy-ray-curable adhesive compositions other than energy-ray-curable adhesive compositions. Examples of non-energy ray-curable adhesive compositions include acrylic resins, urethane resins, rubber resins, silicone resins, epoxy resins, polyvinyl ethers, polycarbonates, The adhesive composition (I-4) containing a non-energy ray-curable adhesive resin (I-1a), such as an ester resin, preferably contains an acrylic resin.

Adhesive compositions other than the adhesive compositions (I-1) to (I-3) preferably contain one or more crosslinking agents, and the content thereof can be set to be the same as that of the above-mentioned adhesive compositions. (I-1) Isochronous same.

＜Adhesive composition (I-4)＞ As a preferable adhesive composition (I-4), what contains the said adhesive resin (I-1a) and a crosslinking agent is mentioned, for example.

[Adhesive resin (I-1a)] Examples of the adhesive resin (I-1a) in the adhesive composition (I-4) include the same as the adhesive resin (I-1a) in the adhesive composition (I-1). The adhesive resin (I-1a) contained in the adhesive composition (I-4) may be 1 type, or may be 2 or more types, and when 2 or more types are used, the combination and ratio of these can be arbitrarily selected.

In the adhesive composition (I-4), relative to the total mass of the adhesive composition (I-4), the content of the adhesive resin (I-1a) is preferably 5-99% by mass, and preferably 10-95% by mass. The mass % is more preferable, and 15-90 mass % is especially preferable.

[Crosslinking agent] As the adhesive resin (I-1a), when the aforementioned acrylic polymer having a structural unit derived from a functional group-containing monomer is used in addition to a structural unit derived from an alkyl (meth)acrylate, the adhesive combination The substance (I-4) preferably further contains a crosslinking agent.

Examples of the crosslinking agent in the adhesive composition (I-4) include the same ones as the crosslinking agent in the adhesive composition (I-1). The crosslinking agent contained in the adhesive composition (I-4) may be only one type, or may be two or more types, and in the case of two or more types, such combinations and ratios can be arbitrarily selected.

In the aforementioned adhesive composition (I-4), the content of the crosslinking agent is preferably 0.01-50 parts by mass, preferably 0.1-20 parts by mass, relative to 100 parts by mass of the content of the adhesive resin (I-1a). Preferably, 0.3 to 15 parts by mass is particularly preferred.

[Other additives] The adhesive composition (I-4) may contain other additives that do not correspond to any of the above-mentioned components within the range that does not impair the effect of the present invention. Examples of the aforementioned other additives include the same ones as the other additives in the adhesive composition (I-1). The other additive contained in the adhesive composition (I-4) may be only one type, or may be two or more types, and in the case of two or more types, such combinations and ratios can be arbitrarily selected.

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

[solvent] The adhesive composition (I-4) may contain a solvent for the same purpose as that of the adhesive composition (I-1). Examples of the aforementioned solvent in the adhesive composition (I-4) include the same ones as the solvent in the adhesive composition (I-1). The solvent contained in the adhesive composition (I-4) may be only one type, or may be two or more types, and in the case of two or more types, such combinations and ratios can be arbitrarily selected. In the adhesive composition (I-4), the content of the solvent is not particularly limited, and may be adjusted appropriately.

<Manufacturing method of adhesive composition> Adhesive compositions other than adhesive compositions (I-1) to (I-3), such as adhesive compositions (I-1) to (I-3), and adhesive composition (I-4), It can be obtained by preparing the above-mentioned adhesive, components other than the above-mentioned adhesive as necessary, and other components for constituting the adhesive composition. The order of addition at the time of compounding of each component is not specifically limited, You may add 2 or more types of components simultaneously. When using a solvent, it is also possible to mix the solvent with any formulation component other than the solvent and use it by diluting the formulation component in advance, or to mix the solvent with the formulation component without pre-diluting any formulation component other than the solvent. The ingredients are mixed and used. The method of mixing the ingredients during preparation is not particularly limited, and the method of mixing by rotating a stirring bar or stirring blade, the method of mixing by using a mixer, and the method of mixing by applying ultrasonic waves are suitable. Just select. The temperature and time for the addition and mixing of each component are not particularly limited as long as the components are not deteriorated, and can be adjusted appropriately. The temperature is preferably 15~30°C

○Films for thermosetting protective film formation The above-mentioned thin film for forming a thermosetting protective film is thermosetting, and finally becomes a protective film with high impact resistance after thermosetting. The protective film prevents, for example, cracks in the semiconductor wafer after the dicing step. The thin film for protective film formation can be formed from the thermosetting protective film formation composition mentioned later.

The film for forming a thermosetting protective film may be one layer (single layer), or multiple layers of two or more layers. When there are multiple layers, these multiple layers may be the same or different from each other, and the combination of these multiple layers is not special limited.

The thickness of the thin film for forming a thermosetting protective film is not particularly limited, but is preferably 1 to 100 μm, more preferably 5 to 75 μm, and particularly preferably 5 to 50 μm. When the thickness of the thin film for thermosetting protective film formation is more than the said lower limit, the adhesive force with respect to the semiconductor wafer of an adherend and a semiconductor wafer becomes large. Moreover, when the thickness of the thin film for thermosetting protective film formation is below the said upper limit, it becomes easier to cut the protective film of hardened|cured material by shearing force at the time of semiconductor wafer pick-up.

As a preferable film for thermosetting protective film formation, the thing containing a polymer component (A) and a thermosetting component (B) is mentioned, for example. The polymer component (A) can be regarded as a component formed by a polymerization reaction of a polymerizable compound. Also, the thermosetting component (B) is a component capable of curing (polymerization) reaction using heat as a reaction trigger. In addition, the polymerization reaction in the present invention also includes polycondensation reaction. Hereinafter, the "thin film for forming a thermosetting protective film" is also simply referred to as "thin film for forming a protective film".

In the present invention, the adhesive force between the protective film obtained by hardening the protective film forming film and the support sheet is preferably 50-1500mN/25mm, more preferably 52-1450mN/25mm, and 53-1430mN/25mm For the best. When the aforementioned adhesive force is above the aforementioned lower limit value, when picking up a semiconductor wafer with a protective film, it is possible to suppress picking up a semiconductor wafer with a protective film outside the target and to selectively pick up a target semiconductor wafer with a protective film. . Moreover, when the said adhesive force is below the said upper limit, when picking up the semiconductor wafer with a protective film, generation|occurrence|production of a crack and a chip|tip in a semiconductor wafer can be suppressed. Thus, the composite sheet for protective film formation has favorable pick-up property by the said adhesive force being in a specific range.

The adhesive force between a protective film and a support sheet can be measured using the following method. That is, the composite sheet for protective film formation with a width of 25 mm and arbitrary length was stuck to an adherend through the film for protective film formation. Next, after thermosetting the film for protective film formation to form a protective film, the support sheet was peeled from this protective film attached to the adherend at a peeling speed of 300 mm/min. The peeling at this time is the so-called 180 degree of peeling the support sheet in its longitudinal direction (the longitudinal direction of the protective film forming composite sheet) so that the contact surfaces of the protective film and the support sheet form an angle of 180∘. ∘ Stripping. And the load (peeling force) at the time of this 180∘ peeling was measured, and the measured value was made into the said adhesive force (mN/25mm).

The length of the composite sheet for protective film formation provided for measurement is not particularly limited as long as the adhesive force can be detected stably, but is preferably 100~300mm. In addition, at the time of measurement, the adherend is attached to the composite sheet for protective film formation, and it is preferable to stabilize the attached state of the composite sheet for protective film formation in advance.

In the present invention, the adhesive force between the protective film forming film and the aforementioned support sheet is not particularly limited, for example, it may be 80mN/25mm or more, preferably 100mN/25mm or more, preferably 150mN/25mm or more, More than 200mN/25mm is especially good. When the above adhesive force is 100mN/25mm or more, peeling of the protective film-forming film and the support sheet can be suppressed during dicing, for example, scattering of the semiconductor wafer having the protective film-forming film on the back surface from the support sheet can be suppressed. On the other hand, the upper limit of the adhesive force between the film for protective film formation and the said support sheet is not specifically limited, For example, it can set it as any of 4000mN/25mm, 3500mN/25mm, 3000mN/25mm etc. But this is an example. As an aspect, the adhesive force between the protective film forming film and the support sheet is preferably 80 mN/25 mm to 4000 mN/25 mm, preferably 100 mN/25 mm to 4000 mN/25 mm, and 150 mN/25 mm. More than 25mm and less than 3500mN/25mm is more preferable, especially preferably more than 200mN/25mm and less than 3000mN/25mm.

The adhesive force between the protective film forming film and the support sheet can be used in the same way as the above-mentioned adhesive force between the protective film and the support sheet except that the protective film forming film to be measured is not hardened by heating. And measure.

The above-mentioned adhesive force between the protective film and the support sheet, and the adhesive force between the film for forming the protective film and the support sheet can be adjusted, for example, by adjusting the type and amount of the ingredients contained in the film for forming the protective film, and the amount of the film on the support sheet. The constituent material of the layer in which the thin film for protective film formation is provided, the surface state of this layer, etc. can be adjusted suitably.

For example, the types and amounts of components contained in the film for forming a protective film can be adjusted by the types and amounts of components contained in the composition for forming a protective film described later. Furthermore, the protective film-forming composition can be adjusted more easily by adjusting, for example, the type and content of the polymer, the content of the filler (D), or the content of the crosslinking agent (F). Adhesion between film or protective film forming film and support sheet.

Also, for example, when the layer on which the film for forming a protective film is provided on the support sheet is an adhesive layer, its constituent material can be appropriately adjusted by adjusting the types and amounts of components contained in the adhesive layer. In addition, the types and amounts of the components contained in the adhesive layer can be adjusted by the types and amounts of the components contained in the above-mentioned adhesive composition. On the other hand, when the layer of the support sheet on which the protective film-forming film is provided is the base material, the adhesive force between the protective film or the protective film-forming film and the support sheet can also be adjusted in addition to the constituent materials of the base material. material surface state. Moreover, the surface state of the base material can be obtained by, for example, performing the surface treatment mentioned above to improve the adhesion between the base material and other layers, that is, roughening treatment by sandblasting, solvent treatment, etc. ;Oxidation treatment such as corona discharge treatment, electron ray irradiation treatment, plasma treatment, ozone‧ultraviolet irradiation treatment, flame treatment, chromic acid treatment, hot air treatment, primer treatment, etc.

As an aspect, the thin film for protective film formation may be thermosetting and energy ray curable, for example, may contain an energy ray curable component (a). The energy ray curable component (a) is preferably uncured, preferably adhesive, and preferably uncured and adhesive. As the energy ray curable component (a), for example, an energy ray curable adhesive resin obtained by introducing a saturated group into a side chain of a non-energy ray curable adhesive resin, an energy ray polymerizable unsaturated group and A monomer or oligomer that can be hardened by irradiation with energy rays.

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

The thickness of the protective film forming film is preferably 1 to 100 μm, more preferably 5 to 75 μm, particularly preferably 5 to 50 μm. When the thickness of the film for protective film formation is more than the said lower limit, the protective film with high protective ability can be formed. Moreover, excess thickness can be suppressed by the thickness of the film for protective film formation being below the said upper limit. Here, the "thickness of the film for forming a protective film" means the thickness of the film for forming a protective film as a whole. The total thickness of all layers of a film.

The curing conditions for forming a protective film by curing the film for forming a protective film are not particularly limited as long as the degree of hardening is such that the protective film can fully perform its function, and may be appropriately selected according to the type of film for forming a protective film. . For example, when the film for forming a protective film is cured, the heating temperature is preferably 50-150°C, and the heating time is preferably 20 minutes-3 hours. Also, when the protective film forming film is thermosetting and energy ray curable, the illuminance of the energy ray is preferably 4 to 280 mW/cm ² . Moreover, the light quantity of the energy ray at the time of curing is preferably 3~1000mJ/cm ² .

<Thermosetting protective film forming composition> The thin film for forming a thermosetting protective film can be formed from a composition for forming a thermosetting protective film containing the constituent materials. For example, the thermosetting protective film-forming film can be formed on the target site by applying the thermosetting protective film-forming composition to the surface to be formed of the thermosetting protective film-forming film and drying it accordingly. The content ratio of the components that do not vaporize at room temperature in the thermosetting protective film forming composition is usually the same as the content ratio of the aforementioned components in the thermosetting protective film forming film. Here, the so-called "normal temperature" is as explained above.

Coating of the composition for forming a thermosetting protective film can be performed, for example, by the same method as that of coating the above-mentioned adhesive composition.

The drying conditions of the composition for forming a thermosetting protective film are not particularly limited. When the composition for forming a thermosetting protective film contains a solvent described later, it is preferable to dry by heating. It is better to dry it under the condition of 10 seconds to 5 minutes.

<Protective film forming composition (III-1)> As a thermosetting protective film-forming composition, for example, a thermosetting protective film-forming composition (III-1) containing a polymer component (A) and a thermosetting component (B) (described in this specification , the "protective film-forming composition (III-1)" is abbreviated), etc.

[Polymer component (A)] The polymer component (A) is a polymer compound for imparting film formability, handleability, etc. to the film for forming a thermosetting protective film. The polymer component (A) contained in the composition for forming a protective film (III-1) and the film for forming a thermosetting protective film may be only one kind, or may be two or more kinds. Combinations and ratios can be selected arbitrarily.

Examples of the polymer component (A) include acrylic resins (such as resins having (meth)acryl groups), polyesters, and urethane resins (such as resins having urethane bonds). , urethane acrylate resin, polysiloxane resin (such as resin with siloxane bond), rubber-based resin (such as resin with rubber structure), phenoxy resin, thermosetting polyimide, etc., Acrylic resins are preferred.

As the above-mentioned acrylic resin in the polymer component (A), known acrylic polymers can be mentioned. The weight average molecular weight (Mw) of the acrylic resin is preferably 10,000-2,000,000, more preferably 100,000-1,500,000. When the weight average molecular weight of an acrylic resin is more than the said lower limit, the shape stability (time-dependent stability at the time of storage) of the film for thermosetting protective film formation improves. In addition, when the weight average molecular weight of the acrylic resin is not more than the above-mentioned upper limit, the film for forming a thermosetting protective film can easily follow the uneven surface of the adherend, and the adhesion between the adherend and the film for forming a thermosetting protective film can be further suppressed. gaps etc. In addition, in this specification, a "weight average molecular weight" means the polystyrene equivalent value measured using the gel permeation chromatography (GPC) method, unless it is mentioned previously.

The glass transition temperature (Tg) of acrylic resin is preferably -60~70°C, more preferably -30~50°C. When Tg of an acrylic resin is more than the said lower limit, the adhesive force of a protective film and a support sheet can be suppressed, and the peelability of a support sheet can improve. Moreover, when Tg of an acrylic resin is below the said upper limit, the adhesive force of the film for thermosetting protective film formation, a protective film, and an adherend improves.

As the acrylic resin, for example, one or more (meth)acrylate polymers can be mentioned; selected from (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene and N- Copolymers of two or more monomers such as methylol acrylamide, etc.

As the aforementioned (meth)acrylate constituting the acrylic resin, for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, ( n-butyl methacrylate, isobutyl (meth)acrylate, second butyl (meth)acrylate, third 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-nonyl (meth)acrylate, Isononyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, lauryl (meth)acrylate (also known as lauryl (meth)acrylate), (meth)acrylate ) tridecyl acrylate, tetradecyl (meth)acrylate (also known as myristyl (meth)acrylate), pentadecyl (meth)acrylate, cetyl (meth)acrylate ((meth) Palm acrylate is also known as), heptadecyl (meth)acrylate, octadecyl (meth)acrylate (also known as (meth)stearyl acrylate), etc. Alkyl (meth)acrylate with a chain structure of 1~18; Cycloalkyl (meth)acrylates such as isocamyl (meth)acrylate and dicyclopentanyl (meth)acrylate; Aralkyl (meth)acrylates such as benzyl (meth)acrylate; Cycloenyl (meth)acrylates such as dicyclopentenyl (meth)acrylate; (Meth)acryloenyloxyalkyl esters such as dicyclopentenyloxyethyl (meth)acrylate; (meth)acrylic imide; Glycidyl group-containing (meth)acrylates such as (meth)acrylic acid glycidyl group; Hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxy(meth)acrylate The hydroxyl groups of butyl, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc. contain (meth)acrylate; (meth)acrylates containing substituted amino groups such as N-methylaminoethyl (meth)acrylate, etc. Here, the "substituted amino group" means a group in which one or two hydrogen atoms of the amino group are substituted with groups other than hydrogen atoms.

Acrylic resin, for example, in addition to the above-mentioned (meth)acrylate, can also be selected from (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene and N-methylolacrylamide, etc. A copolymer of one or more than two monomers.

The monomer which comprises an acrylic resin may be 1 type, and may be 2 or more types, and when there are 2 or more types, the combination and ratio of these can be arbitrarily selected.

The acrylic resin may have functional groups capable of bonding with other compounds, such as vinyl groups, (meth)acryl groups, amine groups, hydroxyl groups, carboxyl groups, and isocyanate groups. The aforementioned functional groups of the acrylic resin may be bonded to other compounds through a crosslinking agent (F) described later, or may be directly bonded to other compounds without passing through a crosslinking agent (F). The acrylic resin is bonded to other compounds through the functional group, and the reliability of the device obtained by using the composite sheet for forming a protective film tends to be improved.

In the present invention, thermoplastic resins other than acrylic resins (hereinafter abbreviated as "thermoplastic resins") may be used in combination with acrylic resins as the polymer component (A). By using the above-mentioned thermoplastic resin, the release property of the protective film from the support sheet is improved, or the film for forming a thermosetting protective film can easily follow the uneven surface of the adherend, and there is further restraint between the adherend and the thermosetting protective film. A case where voids, etc., are generated between thin films for formation.

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

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

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

The aforementioned thermoplastic resin contained in the composition for forming a protective film (III-1) and the film for forming a thermosetting protective film may be 1 type or 2 or more types. When 2 or more types, the combination and ratio of these system can be arbitrarily selected.

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

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

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

As the thermosetting component (B), for example, epoxy-based thermosetting resins, thermosetting polyimides, polyurethanes, unsaturated polyesters, polysiloxane resins, etc., can be mentioned. Sexual resin is preferred.

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

‧Epoxy resin (B1) Examples of the epoxy resin (B1) include conventional ones, for example, polyfunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ester and its hydride, o-cresol novolac Epoxy resin, dicyclopentadiene type epoxy resin, biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenylene skeleton type epoxy resin, etc. Oxygen compounds.

An epoxy resin having an unsaturated hydrocarbon group can also be used as the epoxy resin (B1). Compared with epoxy resins without unsaturated hydrocarbon groups, epoxy resins with unsaturated hydrocarbon groups have higher compatibility with acrylic resins. Therefore, reliability of the device obtained by using the composite sheet for protective film formation improves by using the epoxy resin which has an unsaturated hydrocarbon group.

As an epoxy resin which has an unsaturated hydrocarbon group, the compound which converted a part of the epoxy group of a polyfunctional epoxy resin into the group which has an unsaturated hydrocarbon group is mentioned, for example. Such a compound can be obtained, for example, by adding (meth)acrylic acid or a derivative thereof to an epoxy group. Moreover, as an epoxy resin which has an unsaturated hydrocarbon group, the compound etc. which the group which has an unsaturated hydrocarbon group is directly bonded and constituted the aromatic ring of an epoxy resin, etc. are mentioned, for example. The unsaturated hydrocarbon group is a polymerizable unsaturated group. Specific examples thereof include vinyl (also called vinyl), 2-propenyl (also called allyl), (meth)acryl, (Meth)acrylamide group, etc., preferably acrylyl group. In addition, in this specification, the term "derivative" means a product in which at least one hydrogen atom of the original compound is replaced by a group (substituent) other than a hydrogen atom.

The number average molecular weight of the epoxy resin (B1) is not particularly limited, but it is preferably 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. 300~10000 is better, especially 300~3000. In this specification, the "number average molecular weight" means the number average molecular weight represented by the standard polystyrene equivalent value measured using the gel permeation chromatography (GPC) method, unless otherwise mentioned. The epoxy equivalent of the epoxy resin (B1) is preferably 100-1100 g/eq, more preferably 150-1000 g/eq. In this specification, "epoxy equivalent" means the number of grams (g/eq) of an epoxy compound containing 1 equivalent of an epoxy group, and can be measured according to the method of JISK7236:2001.

The epoxy resin (B1) may be used alone by 1 type, or may use 2 or more types together, and when using 2 or more types together, the combination and ratio of these can be arbitrarily selected.

‧Thermal curing agent (B2) The thermosetting agent (B2) can function as a curing agent for the epoxy resin (B1). As a thermosetting agent (B2), the compound which has 2 or more functional groups which can react with an epoxy group in 1 molecule is mentioned, for example. As the above-mentioned functional group, for example, phenolic hydroxyl group, alcoholic hydroxyl group, amino group, carboxyl group, and acid group are anhydroused, etc., preferably, phenolic hydroxyl group, amino group, or acidic group are anhydroused. A phenolic hydroxyl group or an amino group is preferred.

Among the thermosetting agents (B2), examples of the phenolic curing agent having a phenolic hydroxyl group include polyfunctional phenolic resins, biphenyls, novolak-type phenolic resins, dicyclopentadiene-based phenolic resins, aralkylphenolic resins, and polyfunctional phenolic resins. resin etc. Among the thermosetting agents (B2), the amine-based curing agent having an amino group includes, for example, dicyanodiamine (hereinafter, "DICY" is abbreviated as the case) and the like.

The thermosetting agent (B2) may have an unsaturated hydrocarbon group. Examples of the thermosetting agent (B2) having an unsaturated hydrocarbon group include compounds in which a part of the hydroxyl groups of a phenol resin is substituted by a group having an unsaturated hydrocarbon group, and compounds in which a group having an unsaturated hydrocarbon group is directly bonded to a phenol resin. Compounds formed from aromatic rings, etc. The aforementioned unsaturated hydrocarbon group in the thermosetting agent (B2) is the same as that of the above-mentioned epoxy resin having an unsaturated hydrocarbon group.

When a phenolic curing agent is used as the thermosetting agent (B2), the thermosetting agent (B2) preferably has a higher softening point or glass transition temperature in terms of improving the peelability of the protective film from the support sheet.

The thermosetting agent (B2) is preferably a solid at room temperature and does not show curing activity to the epoxy resin (B1), on the other hand, it is a thermosetting agent that dissolves by heating and shows curing activity to the epoxy resin (B1) agent (hereafter, it is abbreviated as "thermally active latent epoxy resin hardener"). The thermally active latent epoxy resin hardener is a film for forming a thermosetting protective film at room temperature, which is stably dispersed in the epoxy resin (B1), but is compatible with the epoxy resin (B1) by heating And react with epoxy resin (B1). The storage stability of the composite sheet for forming a protective film is remarkably improved by using the aforementioned thermally active latent epoxy resin hardener. For example, migration of the curing agent from the film for forming a protective film to the adjacent support sheet can be suppressed, and a decrease in the thermosetting properties of the film for forming a thermosetting protective film can be effectively suppressed. Furthermore, since the thermosetting degree of the thin film for thermosetting protective film formation becomes high by heating, the pick-up property of the semiconductor wafer with a protective film mentioned later improves further.

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

Among the thermosetting agents (B2), for example, the number average molecular weight of resin components such as polyfunctional phenol resins, novolak-type phenol resins, dicyclopentadiene-based phenol resins, and aralkylphenol resins is preferably 300 to 30,000 , 400~10000 is better, and 500~3000 is especially good. Among the thermosetting agents (B2), for example, the molecular weight of non-resin components such as biphenol and dicyandiamide is not particularly limited, and is preferably 60-500, for example.

A thermosetting agent (B2) may be used individually by 1 type, and may use 2 or more types together, When using 2 or more types together, the combination and ratio of these can be arbitrarily selected.

In the composition (III-1) for forming a protective film and the film for forming a thermosetting protective film, the content of the thermosetting agent (B2) is 0.1 to 500 mass parts with respect to the content of 100 mass parts of the epoxy resin (B1). Parts are better, preferably 1 to 200 parts by mass. When the said content of a thermosetting agent (B2) is more than the said lower limit, hardening|curing of the thin film for thermosetting protective film formation will progress more easily. Moreover, when the said content of a thermosetting agent (B2) is below the said upper limit, the moisture absorption rate of the film for thermosetting protective film formation can be reduced, and the reliability of the module obtained using the composite sheet for protective film formation can be reduced. for further improvement.

In the composition (III-1) for forming a protective film and the film for forming a thermosetting protective film, the content of the thermosetting component (B) (for example, epoxy resin The total content of (B1) and thermosetting agent (B2)) is preferably 1-100 parts by mass, more preferably 1.5-85 parts by mass, and most preferably 2-70 parts by mass. When the said content of a thermosetting component (B) is such a range, the adhesive force of a protective film and a support sheet can be suppressed, and the peelability of a support sheet can be improved.

[Hardening Accelerator (C)] The composition (III-1) for protective film formation and the film for thermosetting protective film formation may contain hardening accelerator (C). The hardening accelerator (C) is a component for adjusting the hardening rate of the composition (III-1) for protective film formation. As a preferred hardening accelerator (C), for example, the third group of triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, ginseng(dimethylaminomethyl)phenol, etc. Class amines; 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4,5-dimethylolimidazole, 2-phenyl-4-methyl -imidazoles such as 5-hydroxymethylimidazole (that is, imidazoles in which at least one hydrogen atom is replaced by a group other than hydrogen atoms); organic phosphines such as tributylphosphine, diphenylphosphine, and triphenylphosphine ( That is, phosphine with at least one hydrogen atom substituted by an organic group); triphenylphosphonium tetraphenyl borate, tetraphenyl boron salt of triphenylphosphonium tetraphenyl borate, etc.

The curing accelerator (C) contained in the composition for forming a protective film (III-1) and the film for forming a thermosetting protective film may be 1 type or 2 or more types, and when 2 or more types are used, the combination of these And the ratio can be selected arbitrarily.

When the hardening accelerator (C) is used, the content of the hardening accelerator (C) is relative to the thermosetting component (B) in the protective film forming composition (III-1) and the thermosetting protective film forming film. The content is 100 parts by mass, preferably 0.01-10 parts by mass, more preferably 0.1-5 parts by mass. When the said content of a hardening accelerator (C) is more than the said lower limit, the effect obtained by using a hardening accelerator (C) can become more remarkable. In addition, when the content of the hardening accelerator (C) is not more than the aforementioned upper limit, for example, the high-polarity hardening accelerator (C) is suppressed from interfering with the film for forming a thermosetting protective film under high temperature and high humidity conditions. The effect of segregation due to movement of the adhesive interface side of the adherend becomes higher, and the reliability of the device obtained by using the composite sheet for forming a protective film is further improved.

[Filler (D)] The composition (III-1) for protective film formation and the film for thermosetting protective film formation may contain a filler (D). By containing the filler (D) in the thermosetting protective film-forming film, the thermal expansion coefficient of the protective film obtained by curing the thermosetting protective film-forming film can be easily adjusted, and by making the thermal expansion coefficient of the protective film The object to be formed is optimized, and the reliability of the module obtained by using the composite sheet for forming a protective film is further improved. Moreover, when the film for thermosetting protective film formation contains a filler (D), the moisture absorption rate of a protective film can also be reduced, and heat dissipation can be improved.

The filler (D) can be any of organic fillers and inorganic fillers, preferably inorganic fillers. Examples of preferable inorganic fillers include powders of silicon oxide, alumina, talc, calcium carbonate, titanium dioxide, red iron oxide, silicon carbide, boron nitride, etc.; Beads; surface-modified products of such inorganic fillers; single crystal fibers of such inorganic fillers; and glass fibers, etc. Among them, the inorganic filler is preferably silicon oxide or aluminum oxide.

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

When the filler (D) is used, in the protective film forming composition (III-1), relative to the total content of all components other than the solvent (the total mass of the protective film forming composition (III-1)), the filler The ratio of the content of (D) (that is, the content of the filler (D) to the total mass of the thermosetting protective film forming film) is preferably 5 to 80% by mass, and more preferably 7 to 60% by mass. good. When the content of the filler (D) is in such a range, it becomes easier to adjust the above-mentioned coefficient of thermal expansion.

[Coupling agent (E)] The composition (III-1) for protective film formation and the film for thermosetting protective film formation may contain coupling agent (E). By using the functional group reactive with an inorganic compound or an organic compound as a coupling agent (E), the adhesiveness and adhesiveness of the film for thermosetting protective film formation to an adherend can be improved. Moreover, water resistance improves the protective film obtained by hardening the thin film for thermosetting protective film formation by using a coupling agent (E), without impairing heat resistance.

The coupling agent (E) is preferably a compound having a functional group capable of reacting with the functional group of the polymer component (A), thermosetting component (B), etc., preferably a silane coupling agent. As preferred aforementioned silane coupling agents, for example, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, propyltriethoxysilane, 3-glycidoxymethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloxy propyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-(2-aminoethylamino)propyltrimethoxysilane, 3-(2-aminoethylamino)propylmethyl Diethoxysilane, 3-(anilino)propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3-ureapropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane Silane, 3-mercaptopropylmethyldimethoxysilane, bis(3-triethoxysilylpropyl)tetrasulfane, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane Oxysilane, vinyltriacetyloxysilane, imidazole silane, etc.

The coupling agent (E) contained in the composition for forming a protective film (III-1) and the film for forming a thermosetting protective film may be 1 type, or 2 or more types, and when there are 2 or more types, the combination and The ratio can be selected arbitrarily.

When the coupling agent (E) is used, the content of the coupling agent (E) in the composition (III-1) for forming a protective film and the film for forming a thermosetting protective film is a combination of the polymer component (A) and the thermosetting property. When the total content of the component (B) is 100 parts by mass, it is preferably 0.03 to 20 parts by mass, more preferably 0.05 to 10 parts by mass, and most preferably 0.1 to 5 parts by mass. When the aforementioned content of the coupling agent (E) is more than the aforementioned lower limit value, the dispersibility of the filler (D) in the resin is improved, and the adhesiveness between the film for forming a thermosetting protective film and an adherend is improved by using a coupling agent (E). The effect obtained by the mixture (E) can be more remarkable. Moreover, when the said content of a coupling agent (E) is below the said upper limit, generation|occurrence|production of outgassing can be suppressed further.

[Crosslinking agent (F)] As the polymer component (A), when using a functional group such as the above-mentioned acrylic resin, etc. , The protective film-forming composition (III-1) and the thermosetting protective film-forming film may contain a crosslinking agent (F) for crosslinking the aforementioned functional group with another compound. By crosslinking using a crosslinking agent (F), the initial adhesive force and cohesive force of the film for thermosetting protective film formation can be adjusted.

Examples of the crosslinking agent (F) include organic polyvalent isocyanate compounds, organic polyvalent imine compounds, metal chelate crosslinking agents (that is, crosslinking agents having a metal chelate structure), aziridine Cross-linking agent (that is, a cross-linking agent having an aziridine group) and the like.

Examples of the organic polyvalent isocyanate compound include aromatic polyvalent isocyanate compounds, aliphatic polyvalent isocyanate compounds, and alicyclic polyvalent isocyanate compounds (hereinafter, these compounds are collectively referred to as "aromatic polyvalent isocyanate compounds" etc. In the case of the above-mentioned aromatic polyvalent isocyanate compounds, trimers, isocyanurate bodies, and adducts thereof; terminal isocyanate urethanes obtained by reacting the aforementioned aromatic polyvalent isocyanate compounds, etc., with polyol compounds prepolymer, etc. The aforementioned "adduct" refers to the aforementioned aromatic polyisocyanate compound, aliphatic polyisocyanate compound or alicyclic polyisocyanate compound, and ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane or castor oil, etc. Examples of the reactant of the low-molecular-weight active hydrogen-containing compound include a xylylene diisocyanate adduct of trimethylolpropane, which will be described later, and the like. In addition, the term "isocyanate-terminated urethane prepolymer" means a prepolymer having an isocyanate group at the end of the molecule while having a urethane bond.

As the aforementioned organic polyvalent isocyanate compound, more specifically, for example, 2,4-toluene diisocyanate; 2,6-toluene diisocyanate; 1,3-xylylene diisocyanate; 1,4-xylene diisocyanate; Isocyanate; Diphenylmethane-4,4'-diisocyanate; Diphenylmethane-2,4'-diisocyanate; 3-Methyldiphenylmethane diisocyanate; Hexamethylene diisocyanate; Isophorone Diisocyanate; dicyclohexylmethane-4,4'-diisocyanate; dicyclohexylmethane-2,4'-diisocyanate; toluene diisocyanate such as trimethylolpropane, hexamethylene diisocyanate and xylylene diisocyanate A compound in which any one or two or more diisocyanates are added to all or part of the hydroxyl groups of a polyol; lysine diisocyanate, etc.

Examples of the aforementioned organic polyimine compound include N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide), trimethylolpropane-tri-β-acridine Cyclopropanyl propionate, Tetramethylolmethane-tri-β-aziridine propionate, N,N'-toluene-2,4-bis(I-aziridine carboxamide) triethylene base melamine etc.

When using an organic polyvalent isocyanate compound as the crosslinking agent (F), it is preferable to use a hydroxyl group-containing polymer as the polymer component (A). When the crosslinking agent (F) has an isocyanate group and the polymer component (A) has a hydroxyl group, by reacting the crosslinking agent (F) with the polymer component (A), it is possible to easily introduce a crosslinked structure into the thermosetting protection A thin film for film formation.

The crosslinking agent (F) contained in the composition for forming a protective film (III-1) and the film for forming a thermosetting protective film may be only one kind, or may be two or more kinds. Combinations and ratios can be selected arbitrarily.

When using a crosslinking agent (F), the content of the crosslinking agent (F) in the protective film forming composition (III-1) is 0.01 to 20 parts by mass relative to 100 parts by mass of the content of the polymer component (A). Parts by mass are preferred, preferably 0.1 to 10 parts by mass, and particularly preferably 0.5 to 5 parts by mass. When the said content of a crosslinking agent (F) is more than the said lower limit, the effect obtained by using a crosslinking agent (F) can become more remarkable. Moreover, when the said content of a crosslinking agent (F) is below the said upper limit, the adhesive force of the film for thermosetting protective film formation and a support sheet, and the bonding force between the thin film for thermosetting protective film formation and a semiconductor wafer can be suppressed. Or the adhesive force of the semiconductor wafer is excessively low. In the present invention, even without using the crosslinking agent (F), the effects of the present invention can be sufficiently obtained.

[energy ray curable resin (G)] The composition (III-1) for protective film formation may contain energy ray curable resin (G). The thin film for thermosetting protective film formation can change a characteristic by irradiation of an energy ray by containing an energy ray curable resin (G).

The energy ray-curable resin (G) can be obtained by polymerizing (curing) an energy ray-curable compound. Examples of the aforementioned energy ray-curable compound include compounds having at least one polymerizable double bond in the molecule, preferably acrylate compounds having a (meth)acryl group.

Examples of the acrylate-based compounds include trimethylolpropane tri(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, neopentylitol tri(meth)acrylate, Neopentylthritol tetra(meth)acrylate, Dineopentylthritol monohydroxypenta(meth)acrylate, Dineopentylthritol hexa(meth)acrylate, 1,4-Butanediol bis(meth)acrylate base) acrylate, 1,6-hexanediol di(meth)acrylate and other (meth)acrylates containing chain aliphatic skeleton; dicyclopentanyl di(meth)acrylate and other containing cycloaliphatic Skeleton (meth)acrylate; polyalkylene glycol (meth)acrylate such as polyethylene glycol di(meth)acrylate; oligoester (meth)acrylate; urethane (meth)acrylate ) acrylate oligomers; epoxy-modified (meth)acrylates; polyether (meth)acrylates other than the aforementioned polyalkylene glycol (meth)acrylates; itaconic acid oligomers, etc.

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

The energy ray-curable compound used for polymerization may be 1 type, or 2 or more types, and when 2 or more types are used, the combination and ratio of these can be arbitrarily selected.

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

The content of the energy ray curable resin (G) in the protective film forming composition (III-1) is preferably 1 to 95% by mass relative to the total mass of the protective film forming composition (III-1). , preferably 2-90% by mass, particularly preferably 3-85% by mass.

[Photopolymerization initiator (H)] When the composition for forming a protective film (III-1) contains an energy ray curable resin (G), in order to efficiently advance the polymerization reaction of the energy ray curable resin (G), a photopolymerization initiator may also be included. (H).

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

The photopolymerization initiator (H) contained in the protective film forming composition (III-1) may be one type, or two or more types, and in the case of two or more types, the combination and ratio of these can be arbitrarily selected. .

The content of the photopolymerization initiator (H) in the protective film forming composition (III-1) is preferably 0.1 to 20 parts by mass relative to 100 parts by mass of the content of the energy ray curable resin (G), Preferably 1-10 parts by mass, particularly preferably 2-5 parts by mass.

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

Examples of the aforementioned organic pigments and organic dyes include amine-based dyes, anthocyanin-based dyes, merocyanidin-based dyes, croconium-based dyes, and squalium-based dyes. , azulenium-based pigments, polymethine-based pigments, naphthoquinone-based pigments, pyrylium-based pigments, phthalocyanine-based pigments, naphthalocyanine-based pigments, naphthalolactamide ( naphtholactam) pigments, azo pigments, condensed azo pigments, indigo pigments, perinone pigments, perylene pigments, diazine pigments, quinacridone pigments, isoindoline Indolinone dyes, quinophthalone dyes, pyrrole dyes, thioindigo dyes, metal complex dyes (metal complex dyes), dithiol metal complex dyes, Indoxyl-based pigments, triallylmethane-based pigments, anthraquinone-based pigments, diazine-based pigments, naphthol-based pigments, imine-based pigments, benzimidazolone-based pigments, pyranthron Department of pigments and shilin (threne) color and so on.

Examples of the aforementioned inorganic pigments include carbon black, cobalt-based pigments, ferric pigments, chromium-based pigments, titanium-based pigments, vanadium-based pigments, zirconium-based pigments, molybdenum-based pigments, ruthenium-based pigments, platinum-based pigments, ITO ( Indium tin oxide) based pigments, ATO (antimony tin oxide) based pigments, etc.

The coloring agent (I) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one type, or two or more types, and when there are two or more types, the combination and The ratio can be selected arbitrarily.

When using a coloring agent (I), what is necessary is just to adjust content of the coloring agent (I) of the film for thermosetting protective film formation suitably according to the objective. For example, when a protective film is printed by laser irradiation, the visibility of printed characters can be adjusted by adjusting the content of the colorant (I) in the film for forming a thermosetting protective film and adjusting the light transmittance of the protective film. . Moreover, by adjusting the coloring agent (I) content of the film for forming a thermosetting protective film, the pattern design property of a protective film can be improved, and the grinding mark on the back surface of a semiconductor wafer can also be made difficult to see. In consideration of this point, the content ratio of the coloring agent (I) (that is, the coloring agent of the thermosetting protective film forming film) is The content of (I)) is preferably 0.1 to 10% by mass, more preferably 0.1 to 7.5% by mass, and most preferably 0.1 to 5% by mass. When the said content of a coloring agent (I) is more than the said lower limit, the effect obtained by using a coloring agent (I) can become more remarkable. Moreover, when the said content of a coloring agent (I) is below the said upper limit, it can suppress that the light transmittance of the film for thermosetting protective film formation falls too much.

[Universal Additive (J)] The composition (III-1) for forming a protective film and the thin film for forming a thermosetting protective film may contain a general-purpose additive (J) within the range that does not impair the effect of the present invention. The general-purpose additive (J) can be a conventional one, and can be arbitrarily selected according to the purpose. It is not particularly limited. As a preferable one, for example, a plasticizer, an antistatic agent, an antioxidant, a degasser, etc. can be mentioned. .

The general-purpose additive (1) contained in the composition for forming a protective film (III-1) and the film for forming a thermosetting protective film may be only one kind, or may be two or more kinds. Combinations and ratios can be selected arbitrarily. The content of the protective film-forming composition (III-1) and the general-purpose additive (1) of the thermosetting protective film-forming 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 solvent-containing composition (III-1) for forming a protective film can improve handleability. The aforementioned solvent system is not particularly limited, and as preferred ones, for example, hydrocarbons such as toluene and xylene; methanol, ethanol, 2-propanol, isobutanol (2-methylpropan-1-ol), 1 -Alcohols such as butanol; Esters such as ethyl acetate and butyl acetate; Ketones such as acetone and methyl ethyl ketone; Ethers such as tetrahydrofuran; Dimethylformamide, N-methylpyrrolidone, etc. Amides (compounds with amide bonds), etc. The solvent contained in the composition (III-1) for protective film formation may be only 1 type, and may be 2 or more types, and when there are 2 or more types, the combination and ratio of these can be arbitrarily selected.

The solvent contained in the protective film-forming composition (III-1) is preferably methyl ethyl ketone or the like in terms of allowing the components contained in the protective film-forming composition (III-1) to be more uniformly mixed. .

<Method for producing thermosetting protective film-forming composition> The thermosetting protective film forming composition, such as the protective film forming composition (III-1), can be obtained by preparing each component which comprises this composition. The order of adding each component is not particularly limited, and two or more components may be added at the same time. When using a solvent, the solvent may be mixed with any one of the prepared ingredients other than the solvent and used by diluting the prepared ingredients beforehand, or may be used without pre-diluting any of the prepared ingredients other than the solvent. Mixed and used. The method of mixing the ingredients during preparation is not particularly limited, and it can be appropriately selected from known methods such as a method of mixing by rotating a stirring bar or a stirring blade, a method of mixing by using a mixer, and a method of mixing by applying ultrasonic waves. That's it. The temperature and time of adding and mixing each component are not particularly limited as long as the components are not deteriorated, and can be adjusted appropriately. The temperature is preferably 15~30°C.

Like the protective film forming composite sheet of the present invention, in order to be attached to the semiconductor wafer or the back surface of the semiconductor wafer opposite to the circuit surface, as a composite sheet provided with a layer showing adhesiveness on the support sheet, a dicing wafer is used. splice sheet. However, the adhesive layer included in the dicing die-bonding sheet functions as an adhesive agent when the semiconductor wafer is mounted on a substrate, lead frame, or other semiconductor wafer, etc. after being picked up from the support sheet together with the semiconductor wafer. On the other hand, the film for forming a protective film in the composite sheet for forming a protective film of the present invention is the same as the above-mentioned adhesive layer in terms of being picked up from the support sheet together with the semiconductor wafer, but finally becomes a protective layer by curing. The film has the function of protecting the back side of the attached semiconductor chip. In this way, the protective film forming film of the present invention and the adhesive layer of the dicing die-bonding sheet have different applications, and of course required performances are also different. And, reflecting the difference in the application, compared with the adhesive layer on the dicing die-bonding sheet, the thin film for protective film formation is generally harder and tends to be more difficult to pick up. Therefore, it is generally difficult to directly transfer the adhesive layer on the dicing die-bonding sheet to the film for protective film formation on the composite sheet for protective film formation. The composite sheet for protective film formation of this invention is provided with the thin film for thermosetting protective film formation, and is required to be excellent in pick-up suitability with respect to the semiconductor wafer with a protective film.

◇Manufacturing method of composite sheet for protective film formation The composite sheet for protective film formation of this invention can be manufactured by laminating|stacking sequentially so that it may become the positional relationship corresponding to each layer mentioned above. The method of forming each layer is as described above. For example, when laminating an adhesive layer on a base material at the time of manufacturing a support sheet, what is necessary is just to coat the said adhesive agent composition on a base material, and to dry it as needed.

On the other hand, for example, when the protective film forming film is further laminated on the adhesive layer that has been laminated on the substrate, the protective film forming composition can be coated on the adhesive layer to directly form the protective film forming film. film. The layer other than the film for protective film formation can also use the composition for forming this layer, and this layer can be laminated|stacked on an adhesive agent layer by the same method. In this way, when forming a continuous two-layer laminated structure using any of the compositions, a new layer can be formed by further applying the composition on the layer formed from the aforementioned composition. However, among these two layers, it is preferable that the layer laminated later is formed on another release film using the aforementioned composition in advance, and the side of the formed layer that is in contact with the aforementioned release film is reversed. The exposed surface of the side is bonded to the exposed surface of the remaining layer that has already been formed to form a laminated structure of two consecutive layers. In this case, the aforementioned composition is preferably applied to the release-treated surface of the release film. After the release film forms a laminated structure, it may be removed as necessary.

For example, a composite sheet for protective film formation in which an adhesive layer is laminated on a base material and a film for forming a protective film is laminated on the adhesive layer (the support sheet is a laminate of the base material and the adhesive layer) In the case of a composite sheet for forming a protective film), the adhesive layer is laminated on the substrate in advance by applying the adhesive composition on the substrate and drying it as necessary, and by applying the protective film The composition for formation is applied on the release film, and dried as necessary to form a thin film for forming a protective film on the release film in advance. Then, the protective film can be obtained by laminating the protective film forming film on the adhesive layer by bonding the exposed surface of the protective film forming film to the exposed surface of the adhesive layer laminated on the substrate. A composite sheet is formed.

Also, when laminating the adhesive layer on the substrate, as described above, the adhesive composition may be applied to the release film instead of the method of applying the adhesive composition to the substrate, and the The adhesive layer is formed in advance on the release film by drying, and the adhesive layer is laminated on the substrate by bonding the exposed surface of the layer to one surface of the substrate. In either method, the peeling film may be removed at any timing after forming the target laminated structure.

In this way, any layer other than the base material constituting the composite sheet for forming a protective film can be laminated by using a method of forming a release film in advance and sticking it to the surface of the target layer, so it is appropriately selected as necessary. What is necessary is just to manufacture the composite sheet for protective film formation by taking the layer of such a procedure.

Moreover, the composite sheet for protective film formation can normally be stored in the state which bonded the peeling film to the surface of the outermost layer (for example, the film for protective film formation) on the opposite side to the support sheet. Therefore, by applying a composition for forming a layer constituting the outermost layer, such as a protective film-forming composition, on the release film (preferably, its release-treated surface), drying it as necessary, the release film is preliminarily coated. The layer constituting the outermost layer is formed on the top layer, and the remaining layers are laminated on the exposed surface of the layer opposite to the side in contact with the release film by any of the above methods. Even if the release film is not removed, it can be attached In the combined state, a composite sheet for forming a protective film was obtained.

◎Manufacturing method of semiconductor wafer with protective film The manufacturing method of the semiconductor wafer with protective film of the present invention comprises the following steps: A step of laminating semiconductor wafers on the protective film forming composite sheet on the side of the aforementioned thermosetting protective film forming thin film to produce a laminate; A step of irradiating the inside of the semiconductor wafer of the laminate with laser light to form a modified layer inside the semiconductor wafer; a step of heating and hardening the aforementioned thin film for forming a thermosetting protective film of the aforementioned laminate to form a protective film; and A step of cold-expanding the laminate at a temperature lower than normal temperature to divide the semiconductor wafer, the thin film for forming a thermosetting protective film, or the protective film. Furthermore, the manufacturing method may include obtaining a semiconductor wafer with a protective film by peeling the divided semiconductor wafer together with the protective film laminated on the semiconductor wafer from the support sheet and picking it up.

The method of manufacturing a semiconductor wafer with a protective film according to the present invention may also include the steps of laminating the semiconductor wafer on the side of the aforementioned thermosetting protective film forming thin film of the protective film forming composite sheet to form a laminated film. After the step of bulking, the step of irradiating laser light to the inside of the aforementioned semiconductor wafer of the aforementioned laminated body to form a modified layer inside the aforementioned semiconductor wafer; performing cold expansion of the aforementioned laminated body at a temperature lower than normal temperature to a step of dividing the semiconductor wafer and the thin film for forming a thermosetting protective film; and a step of heating and curing the thin film for forming a thermosetting protective film of the laminate to form a protective film. An example of the method of manufacturing the semiconductor wafer with a protective film will be described using FIG. 3 .

First, after the back surface of the semiconductor wafer 18 is ground to a desired thickness, the back surface of the semiconductor wafer 18 after the back grinding is attached to the thermosetting protective film forming film 23 of the protective film forming composite sheet 2. At the same time, the composite sheet 2 for protective film formation is fixed to the ring frame 17 (FIG. 3(a)). When the back grinding tape 720 is attached to the surface (electrode formation surface) of the semiconductor wafer 18 , the semiconductor wafer 18 is removed from the back grinding tape 20 .

Next, from the side of the composite sheet 2 for forming a protective film, laser light (SD) is irradiated so as to focus on the focus set inside the semiconductor wafer 18 to form the modified layer 18c inside the semiconductor wafer 18. (Figure 3(b)). Here, laser printing is performed by irradiating laser light from the side of the support sheet 10 as necessary. Next, the semiconductor wafer 18 on which the modified layer is formed and the protective film forming composite sheet 2 is attached on the back is cold expanded in the plane direction of the protective film forming composite sheet together with the protective film forming composite sheet 2 (CE), while cutting the thin film for forming a curable protective film, the semiconductor wafer 18 is divided and individualized at the portion of the modified layer 18 c ( FIG. 3 ( c )). Here, infrared inspection is performed by irradiating infrared laser light from the side of the support sheet 10 as necessary.

In the composite sheet 2 for forming a protective film of the present invention, the loss positive connection (tan δ) of the base material 11 of the support sheet 10 at -15° C. is 0.05 or more, the cold resistance of the base material 11 becomes good, and by The base material 11 of the support sheet 10 will not be cracked by performing cold expansion (CE) at room temperature.

Then, the laminate of the support sheet 10, the individualized thermosetting protective film forming film 23, and the individualized semiconductor wafer 19 is heated to harden the thermosetting protective film forming film 23 to form a protective film. 23' (Fig. 3(d)).

In the composite sheet 2 for forming a protective film of the present invention, the base material 11 of the support sheet 10 has a storage elastic modulus (G') of 35.0 MPa or more at 80° C. Under the condition of heating and hardening, the support sheet 10 will not bend, and even in a small gap, the support sheet 10, the thin film 23 for forming a thermosetting protective film that has been singulated, and the semiconductor wafer 19 that has been singulated are separated. The thermosetting protective film forming thin film 23 is heated and cured in a state where many laminates are stacked, and it is also possible to prevent the support sheet 10 from contacting the other semiconductor wafer 19 on the lower side.

Finally, the semiconductor wafer 19 with the protective film 23' attached to the back surface is peeled and picked up from the support sheet 10 to obtain the semiconductor wafer 19 with the protective film 23' (FIG. 3(e)). For example, the support sheet 10 is formed by laminating a base material 11 and an adhesive layer 12. When the adhesive layer 12 is an energy ray curable material, the adhesive layer 12 is cured by irradiating energy rays, and the cured adhesive layer 12 is cured. The adhesive layer 12 is used to pick up the semiconductor wafer 19 together with the protective film 23 ′ affixed on its back, and the semiconductor wafer 19 with the protective film 23 ′ can be obtained more easily.

In FIG. 3 , an example of a method of manufacturing a semiconductor wafer with a protective film using a protective film-forming composite sheet 2 having an adhesive layer 16 for a jig has been described, and a protective film without an adhesive layer 16 for a jig is used. The same applies to the example of the manufacturing method of the semiconductor wafer with the protective film of the composite sheet 1 for film formation.

Also, in FIG. 3 , from the side of the composite sheet 2 for forming a protective film, laser light (SD) is irradiated so as to focus on a focal point set inside the semiconductor wafer 18 to form a modification in the inside of the semiconductor wafer 18. The modified layer, but not limited thereto, may also include the step of forming the aforementioned modified layer; the step of becoming the aforementioned laminate; the aforementioned step of dividing; and the step of becoming the aforementioned protective film. A modified layer is formed inside the semiconductor wafer 18 on which the back grinding tape 20 is attached, and the composite sheet 2 for forming a protective film is attached to the semiconductor wafer 18 on which the modified layer is formed. Subsequently, laser printing is performed by irradiating laser light from the side of the support sheet 10 , cold expansion (CE), thermal curing, infrared inspection, and picking are performed to obtain a semiconductor wafer 19 with a protective film 23 ′.

The method for manufacturing a semiconductor wafer with a protective film according to the present invention may also include the steps of laminating the semiconductor wafer on the side of the aforementioned thermosetting protective film forming thin film of the protective film forming composite sheet to form a After the step of the laminate, the step of heating and hardening the thin film for forming the thermosetting protective film of the laminate to form a protective film; the step of irradiating the inside of the semiconductor wafer with laser light to form a modified layer inside the semiconductor wafer ; and the step of cold-expanding the above-mentioned laminated body at a temperature lower than normal temperature to divide the above-mentioned semiconductor wafer and the above-mentioned protective film. An example of the manufacturing method of this semiconductor wafer with a protective film is demonstrated using FIG. 4. FIG.

First, after the back surface of the semiconductor wafer 18 is ground to a desired thickness, the thermosetting protective film forming film is attached to the protective film forming composite sheet 2 on the back surface of the semiconductor wafer 18 after the back grinding. At the same time as 23, the protective film forming composite sheet 2 is fixed to the annular frame 17 (FIG. 4(a)). When the back grinding tape 20 is attached to the surface (electrode formation surface) of the semiconductor wafer 18 , the back grinding tape 20 is removed from the semiconductor wafer 18 .

Next, the laminate composed of the support sheet 10, the thin film 23 for forming a thermosetting protective film, and the semiconductor wafer 18 is heated to heat and harden the thin film 23 for forming a thermosetting protective film to form a protective film 23' (Fig. (b)).

In the composite sheet 2 for forming a protective film of the present invention, the base material 11 of the support sheet 10 has a storage elastic modulus (G') of 35.0 MPa or more at 80° C. Under heat curing conditions, the support sheet 10 does not bend, and even in a small gap, in the state where the support sheet 10, the thin film 23 for forming a thermosetting protective film, and the laminated body of the semiconductor wafer 18 are mostly stacked, Heat-curing the thermosetting protective film-forming thin film 23 can also prevent the support sheet 10 from coming into contact with another semiconductor wafer 18 on the lower side.

Then, from the protective film 23' side, laser light (SD) is irradiated so as to focus on the focus set inside the semiconductor wafer 18, and the modified layer 18c is formed inside the semiconductor wafer 18 (FIG. (c)). Here, laser printing is performed by irradiating laser light from the side of the support sheet 10 as necessary. Next, the semiconductor wafer 18 on which the modified layer 18c is formed and the protective film forming composite sheet 2 is attached on the back is cooled in the plane direction of the protective film forming composite sheet 2 together with the protective film forming composite sheet 2. Expanding (CE), the protective film 23 ′ is cut, and the semiconductor wafer 18 is divided and individualized at the portion of the modified layer 18 c ( FIG. 4 ( d )). Here, infrared inspection is performed by irradiating infrared laser light from the side of the support sheet 10 as necessary.

In the composite sheet 2 for forming a protective film of the present invention, the loss positive connection (tan δ) of the base material 11 of the support sheet 10 at -15° C. is 0.05 or more, the cold resistance of the base material 11 becomes good, and by The base material 11 of the support sheet 10 will not be cracked by performing cold expansion (CE) at room temperature.

Finally, the semiconductor wafer 19 with the protective film 23' attached to the back surface is peeled off and picked up from the support sheet 10 to obtain the semiconductor wafer 19 with the protective film 23' (FIG. 4(e)). For example, the support sheet 10 is formed by laminating a base material 11 and an adhesive layer 12. When the adhesive layer 12 is an energy ray curable material, the adhesive layer 12 is cured by irradiating energy rays, and the cured adhesive layer 12 is cured. The adhesive layer 12 is used to pick up the semiconductor wafer 19 together with the protective film 23 ′ attached to the back surface thereof, and the semiconductor wafer 19 with the protective film 23 ′ can be obtained.

In the method for manufacturing a semiconductor wafer with a protective film of the present invention, the order of each step is not limited to the above-mentioned order, and after heating and curing, laser light is irradiated from the side of the support sheet to carry out laser printing, and then Cold Extension (CE). After hardening the adhesive layer 12 by irradiating energy rays as necessary, the semiconductor wafer 19 with the protective film 23 ′ can be picked up. The method for manufacturing a semiconductor wafer with a protective film according to the present invention may also include the following steps in sequence: the step of forming the aforementioned modified layer; the step of manufacturing the aforementioned laminate; the step of forming the aforementioned protective film; and the step of performing the aforementioned division; The following steps may also be included in order: the step of manufacturing the aforementioned laminate; the step of forming the aforementioned modified layer; and the step of forming the aforementioned protective film.

◎Semiconductor device manufacturing method Afterwards, the same method as the previous method can be used to connect the obtained semiconductor wafer with a protective film to the circuit surface of the substrate in the state where the protective film is attached. as a semiconductor component. Furthermore, it is only necessary to manufacture a target semiconductor device using this semiconductor module.

As an aspect, the composite sheet for forming a protective film of the present invention includes a support sheet having a base material and an adhesive layer; and a thermosetting film for forming a protective film provided on the support sheet; The composite sheet is formed by sequentially laminating the aforementioned base material, the aforementioned adhesive layer, and the aforementioned thermosetting protective film forming film; the aforementioned base material has the following characteristics: the loss positive connection (tanδ) at -15°C is 0.05 above, preferably above 0.06 and below 0.09, and the storage elastic modulus (G') at 80°C is above 35.0MPa, preferably above 60MPa and below 150MPa; Cut the long side 110mm x short side 22mm so that the MD direction or CD direction becomes the long side direction, heat at 130°C for 2 hours under a load of 2.2g in such a way that the measurement distance before heating becomes about 100mm, and then Let cool and measure at 23°C, and measure the distance between measurements after heating as _L1 , when cutting out the MD direction of the above-mentioned substrate as the long side, or when cutting out the CD direction of the above-mentioned substrate as the long side Both of them are that the thermal expansion rate X represented by formula (1) is more than -3% and less than +3%, preferably 0~2.2%; the aforementioned substrate is preferably made of polybutylene terephthalate containing soft components A film made of diester, a three-layer transparent film made of a blended resin of polypropylene (PP) and olefin-based thermoplastic elastomer (TPO), or polyethylene (PE)/polypropylene (PP)/polyethylene (PE) 3-layer transparent film; the aforementioned adhesive layer is preferably non-energy ray curable; the aforementioned adhesive layer is preferably made of (meth)acrylate copolymer (2-ethylhexyl acrylate , methyl methacrylate and 2-hydroxyethyl acrylate 10 copolymers obtained by copolymerization), bisphenol A type epoxy resin, and an adhesive composition of a cross-linking agent are formed; the film system for forming the protective film It is preferably an acrylic polymer containing a polymer component (preferably an acrylic polymer formed by copolymerizing methyl acrylate and 2-hydroxyethyl acrylate), epoxy resin (preferably bisphenol A type epoxy resin and bicyclic pentadiene type epoxy resin), hardener (preferably thermally active latent epoxy resin hardener), effect accelerator (preferably 2-phenyl-4,5-dimethylolimidazole), filler A protective film-forming composition of an agent (preferably a silica filler), a coupling agent (preferably a silane coupling agent), and a colorant (preferably a three-color mixed pigment). Moreover, the thickness of the base material of the composite sheet for forming the protective film is preferably 15-300 μm, preferably 50-200 μm, more preferably 60-150 μm, and particularly preferably 70-100 μm; the thickness of the aforementioned adhesive layer , is preferably 3-20 μm, more preferably 10-15 μm; the thickness of the protective film forming film is preferably 1-100 μm, more preferably 5-75 μm, more preferably 5-50 μm, 5~30μm is particularly preferred. [Example]

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

[Example 1] ＜Manufacture of composite sheet for protective film formation＞ (Manufacture of protective film forming composition (III-1)) The components used for manufacture of the composition for protective film formation are shown below. ‧Polymer composition (A): An acrylic polymer obtained by copolymerizing 90 parts by mass of methyl acrylate and 10 parts by mass of 2-hydroxyethyl acrylate (weight average molecular weight: 400,000) ‧Epoxy resin (B1)-1: Bisphenol A type epoxy resin (jER828 manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 184~194g/eq) (B1)-2: Bisphenol A type epoxy resin (jER1055 manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 800~900g/eq) (B1)-3: Dicyclopentadiene type epoxy resin (Epiclon HP-7200HH manufactured by DIC Corporation, epoxy equivalent 255~260g/eq) ‧hardener (B2): thermally active latent epoxy resin hardener (dicyandiamide (Mitsubishi Chemical Corporation DICY7 active hydrogen content 21g/eq)) ‧Hardening Accelerator (C): 2-phenyl-4,5-dimethylolimidazole (CUREZOLE 2PHZ manufactured by Shikoku Chemical Industry Co., Ltd.) ‧Filler (D) Silica filler (SC205G-MMQ manufactured by ADMATECHS Co., Ltd. with an average particle diameter of 0.3 μmm) ‧Coupling agent (E): Silane coupling agent (X-41-1056 manufactured by Shin-Etsu Chemical Co., Ltd.) ‧Colorant (I): Three-color mixed pigment (D1201M manufactured by Sanyo Pigment Co., Ltd., solid content concentration 30%)

Polymer component (A), epoxy resin (B1)-1, epoxy resin (B1)-2, epoxy resin (B1)-3, hardener (B2), hardening accelerator (C), filler (D), coupling agent (E) and coloring agent (I) are dissolved in such a manner that the contents (solid content, parts by mass) become 150/60/10/30/2/2/320/2/1.2 or It was dispersed in methyl ethyl ketone and stirred at 23°C to prepare a protective film-forming composition (III-1) having a solid content concentration of 50% by mass.

(Manufacture of Adhesive Composition (I-4)) The components used in the manufacture of the adhesive composition are shown below. ‧Polymer composition (a): As the binder polymer, a (meth)acrylate copolymer (60 parts by mass of 2-ethylhexyl acrylate, 30 parts by mass of methyl methacrylate, 10 parts by mass of 2-hydroxyethyl acrylate Copolymer obtained by copolymerization. Weight average molecular weight: 400,000) ‧Epoxy resin (b): Bisphenol A epoxy resin (jER828 manufactured by Mitsubishi Chemical, epoxy equivalent 184~194g/eq) ‧Crosslinking agent components (c): 3-functional XDI crosslinking agent (TAKENATE (registered trademark) D-11ON manufactured by Mitsui Chemicals) [0266]

Preparation contains polymer component (a) (100 mass parts, solid content), epoxy resin (b) (16 mass parts, solid content) and crosslinking agent component (c) (25 mass parts, solid content), and contains A non-energy ray-curable adhesive composition (I-4) in which methyl ethyl ketone is used as a solvent and the solid content concentration is 30% by mass.

(manufacture of support sheet) The above-mentioned product was applied to the release-treated surface of a release film ("SP-PE1381031" manufactured by LINTEC Co., Ltd., thickness 38 μm) that was released by silicone treatment on one side of a polyethylene terephthalate film. The adhesive composition (I-4) was heated and dried at 120° C. for 2 minutes to form a non-energy ray-curable adhesive layer with a thickness of 10 μm. Next, a polybutylene terephthalate film (thickness 80 μm, Young’s modulus at 23°C: 500 MPa) containing a soft component was attached to the exposed surface of the adhesive layer as a base material to obtain the above-mentioned base material. A transparent support sheet (10)-1 with the aforementioned adhesive layer on one surface.

(Manufacture of composite sheets for protective film formation) Use a knife coater on the release-treated surface of a release film ("SP-PE1381031" manufactured by LINTEC Co., Ltd., thickness 38 μm) that has been released by silicone treatment on one side of a polyethylene terephthalate film. The protective film-forming composition (III-1) obtained above was applied and dried at 100° C. for 2 minutes to manufacture a thermosetting protective film-forming film (13)-1 with a thickness of 25 μm.

Next, the release film was removed from the adhesive layer of the support sheet (10)-1 obtained above, and the film (13)-1 for forming a thermosetting protective film obtained above was attached to the exposed surface of the adhesive layer. The exposed surface of the substrate, the adhesive layer, the thermosetting protective film forming film (13)-1, and the release film are laminated in this order in the thickness direction to produce the protective film of Example 1. Use composite sheets.

<Cold Resistance Test of Composite Sheet for Protective Film Formation> (Steps to becoming a laminate) After attaching the back grinding tape ADWILLE-8180HR (manufactured by LINTEC Co., Ltd.) to a 12-inch bare silicon wafer (thickness: 775 μm) using a tape bonding machine RAD-3510 (manufactured by LINTEC Co., Ltd.), use FU11AUTO GRINDER DG P8760 (DISCO (manufactured by the company) Grind a silicon wafer (thickness: 300 μm, grinding surface: #2000). Subsequently, the release film of the protective film forming composite sheet 2 of Example 1 was peeled off using a tape bonding machine RAD-2700 (manufactured by Lintec Co., Ltd.), and then attached to the ground surface of the silicon wafer to manufacture a laminate. sample. After attaching the annular frame 17 to the laminate sample, the ADWILLE-8180HR attached to the surface layer of the laminate sample was irradiated with UV using a UV irradiation device RAD-2000 (manufactured by Lintec Co., Ltd.), and then peeled off.

(Step of forming modified layer) Then, laser is irradiated from the surface layer of the silicon wafer toward the composite sheet 2 for protective film formation using a laser cutter DFL7361 (manufactured by DISCO Co., Ltd.), and the laser dicing is performed so that the wafer size: 1mm×1mm, and the silicon wafer 18 A modified layer is formed inside (the left side of Fig. 5).

(cold expansion step) The entire laminate sample of the silicon wafer 18 having the modified layer formed therein and the composite sheet 2 for forming a protective film obtained above was cooled at -15°C in an expander DDS2300 (manufactured by DISCO Corporation). Under the conditions of a push-up speed of 20 mm/sec and a push-up amount of 20 mm, the laminate sample was cold-expanded in the plane direction of the thermosetting protective film forming film 23 by pushing up the table. Thereby, while cutting the thin film 23 for forming a thermosetting protective film, the silicon wafer 18 is divided at the portion of the reformed layer to obtain a plurality of semiconductor wafers 19 with a size of 1 mm×1 mm (right side in FIG. 5 ). .

(cold resistance test) After the above-mentioned cold expansion step, whether or not the base material is broken was checked visually. The base material of the composite sheet for protective film formation was rated as "P" and the base material of the composite sheet for protective film formation was cracked as "Q".

＜Heat Resistance Test of Composite Sheet for Protective Film Formation＞ Using a tape bonding machine RAD-2700 (manufactured by LINTEC), peel off the release film of the composite sheet 1 for protective film formation and attach it to the grinding surface of a 12-inch silicon wafer (thickness: 300 μm grinding surface: #2000). beveled to produce laminate samples. After this laminate sample was mounted on the ring frame 17, the support sheet 10 was evaluated when the thermosetting protective film forming film 13 was thermally cured under the conditions of 130° C. and 2 hours (hours) to form a protective film 13 ′. The maximum sinking amount d (Figure 6).

The thing whose maximum sinking amount is less than 2.0 mm is evaluated as "P", and the thing whose maximum sinking amount is more than 2.0 mm is rated as "Q".

<Heat load test> Cut out the base material of the composite sheet for protective film formation so that the MD direction (that is, the flow direction) becomes the long side direction. The distance between the clips (measurement distance L ₀ ) becomes about 100mm, and it is heated at 130°C for 2 hours under a load of 2.2g (that is, the load is 2.2g/22mm=0.lg/mm), and then After cooling, the distance between clips after heating at 23° C. (measurement distance L ₁ ) was measured, and the thermal expansion ratio X (MD: long side) represented by the following formula (1) was obtained. X=(L ₁ -L ₀ )/L ₀ ×100…(1)

The base material of the composite sheet for protective film formation is cut out in such a way that the CD direction (that is, the width direction) becomes the long side direction, and the long side is 110mm x the short side is 22mm, and the thermal expansion rate X'( CD: long side).

＜Dynamic viscoelasticity measurement＞ The loss elastic modulus and storage elastic modulus of the base material of a support sheet were measured using RHEOVIBRON (registered trademark) DDV-01FP (product name) manufactured by A&D Co., Ltd. under the following conditions. The ratio of the loss elastic modulus/storage elastic modulus at -15°C (that is, the loss positive connection (tan δ)) was obtained from the measured values. Also, the storage elastic modulus (G') at 80°C was obtained. Sample size: long side 20mm (distance between clamps), short side 4mm, thickness (thickness of each substrate sample). However, it is cut so that the MD direction becomes the longitudinal direction. Measuring conditions: -50°C~80°C, 3°C/min Measuring Mode: Stretch Mode Frequency: 10Hz

(measurement of thickness) It measured using a constant pressure thickness measuring device (manufactured by Teclock Corporation, product name "PG-02").

Table 1 shows the results of the heat load test, cold resistance test, and heat resistance test of the composite sheet for protective film formation of Example 1. In the composite sheet for forming a protective film of Example 1, the base material of the support sheet was not cracked by cold expansion, and the support sheet did not bend even when the thermosetting protective film forming film was heated and hardened.

[Example 2] ＜Manufacture and evaluation of protective film forming composite sheet＞ Except that the base material is a three-layer transparent film (thickness: 80nm, Younger's modulus at 23°C 50MPa) composed of a mixed resin of polypropylene (PP) and olefin-based thermoplastic elastomer (sometimes abbreviated as TPO). Except that, it carried out similarly to Example 1, and manufactured the composite sheet for protective film formation of Example 2.

Table 1 shows the results of the thermal load test, the cold resistance test, and the heat resistance test of the composite sheet for protective film formation of Example 2. In the composite sheet for forming a protective film of Example 2, the base material of the support sheet was not cracked by cold expansion, and the support sheet did not bend even when the thermosetting protective film forming film was heated and hardened.

[Example 3] ＜Manufacture and evaluation of protective film forming composite sheet＞ Except that the base material is a three-layer transparent film of polyethylene (PE)/polypropylene (PP)/polyethylene (PE) (thickness: 80m, Young's modulus at 23°C: 500MPa), it is the same as Example 1 The composite sheet for protective film formation of Example 3 was manufactured by proceeding.

Table 1 shows the results of the thermal load test, the cold resistance test, and the heat resistance test of the composite sheet for protective film formation of Example 3. In the composite sheet for forming a protective film of Example 3, the substrate of the support sheet was not cracked due to cold expansion, and the support sheet did not bend even when the thermosetting protective film forming film was heated and hardened.

[Comparative example 1] ＜Manufacture and evaluation of protective film forming composite sheet＞ Except that the base material is a two-layer transparent film of polypropylene (PP)/polypropylene (PP) (thickness: 15 μm + 65 μm = 80 μm, Young’s modulus at 23° C. is 500 MPa), it is carried out in the same manner as in Example 1. A composite sheet for forming a protective film of Comparative Example 1 was produced.

Table 1 shows the results of the heat load test, cold resistance test, and heat resistance test of the composite sheet for protective film formation of Comparative Example 1. In the composite sheet for forming a protective film of Comparative Example 1, the support sheet was not bent even under the conditions of heating and hardening the thermosetting protective film forming film, but the base material of the support sheet was cracked due to cold expansion.

[Comparative example 2] ＜Manufacture and evaluation of protective film forming composite sheet＞ A protective film-forming composite sheet of Comparative Example 2 was produced in the same manner as in Example 1, except that the base material was a polyethylene (PE) transparent film (thickness: 110 μm, Younger modulus at 23°C: 140 MPa). .

Table 1 shows the results of the heat load test, cold resistance test, and heat resistance test of the composite sheet for protective film formation of Comparative Example 2. In the composite sheet for forming a protective film of Comparative Example 2, although the base material of the support sheet was not cracked by cold expansion, the support sheet was bent under the conditions of heating and curing the thermosetting protective film forming film.

[Comparative example 3] ＜Manufacture and evaluation of protective film forming composite sheet＞ A protective film-forming composite sheet of Comparative Example 3 was produced in the same manner as in Example 1, except that the base material was a transparent film made of polypropylene (PP) (thickness: 60 μm, Younger modulus at 23°C: 150 MPa). .

Table 1 shows the results of the heat load test, cold resistance test, and heat resistance test of the composite sheet for protective film formation of Comparative Example 3. In the composite sheet for forming a protective film of Comparative Example 3, the support sheet did not bend even under the conditions of heating and curing the thermosetting protective film forming film, but the base material of the support sheet was cracked due to cold expansion.

[Table 1]

As can be clearly seen from the results of Examples 1 to 3, in the composite sheet for forming a protective film of the present invention, the storage modulus of elasticity ( G') is 35.0 MPa or more, the base material of the support sheet will not be cracked due to cold expansion, and the support sheet will not bend even under the condition of heating and hardening the film for forming a thermosetting protective film. Industrial availability

The present invention is industrially very useful because it can be suitably utilized in the manufacture of a semiconductor wafer with a protective film by a method of dividing by cold expansion.

1. 2‧‧‧Composite sheet for protective film formation 10‧‧‧Support piece 10a‧‧‧Support surface 11‧‧‧Substrate 11a‧‧‧Substrate surface 12‧‧‧adhesive layer 12a‧‧‧The surface of the adhesive layer 13.23‧‧‧Films for forming thermosetting protective films 13a, 23a‧‧‧The surface of the film for forming a thermosetting protective film 13', 23'‧‧‧Protective film 15‧‧‧Peeling film 15a‧‧‧Peeling film surface 16‧‧‧adhesive layer for jig 16a‧‧‧The surface of the adhesive layer for jigs 17‧‧‧ring frame 18‧‧‧Semiconductor wafer (silicon wafer) 18a‧‧‧The back side of the semiconductor wafer 18c‧‧‧modified layer 19‧‧‧semiconductor chip 20‧‧‧Back grinding tape SD‧‧‧Laser light irradiation CE‧‧‧Cold expansion

Fig. 1 is a cross-sectional view schematically showing an embodiment of the composite sheet for forming a protective film of the present invention. Fig. 2 is a cross-sectional view schematically showing another embodiment of the composite sheet for forming a protective film of the present invention. Fig. 3 is a cross-sectional view schematically showing an example of a method of manufacturing a semiconductor wafer with a protective film. Fig. 4 is a cross-sectional view schematically showing another example of the method of manufacturing a semiconductor wafer with a protective film. Fig. 5 is a cross-sectional view schematically showing a cold resistance test method of a composite sheet for forming a protective film. Fig. 6 is a cross-sectional view schematically showing a heat resistance test method of a composite sheet for forming a protective film.

1‧‧‧Composite sheet for protective film formation

10‧‧‧Support piece

10a‧‧‧Support surface

11‧‧‧Substrate

11a‧‧‧Substrate surface

12‧‧‧adhesive layer

12a‧‧‧The surface of the adhesive layer

13‧‧‧Film for forming thermosetting protective film

13a‧‧‧The surface of the film for forming a thermosetting protective film

15‧‧‧Peeling film

15a‧‧‧Peeling film surface

Claims (6)

A composite sheet for forming a protective film, comprising: a support sheet having a substrate; and a thermosetting protective film forming film on the support sheet, the substrate having a loss positive connection (tanδ) at -15°C It is 0.05 or more and the storage elastic modulus (G') at 80°C is 35.0 MPa or more. The composite sheet for forming a protective film as described in claim 1, wherein the base material has a length of 110 mm x a short side of 22 mm cut out so that the MD direction or CD direction of the base material becomes the long side direction, and heated When the previous measurement distance L ₀ becomes about 100 mm and the load state of 2.2 g is heated at 130° C. for 2 hours, and then cooled to measure the measurement distance L ₁ after heating at 23° C., the above-mentioned Either when the MD direction of the substrate is taken as the long side or when the CD direction of the above-mentioned substrate is taken as the long side, the thermal expansion ratio X represented by the following formula (1) is -3% or more and + The characteristic below 3%, X=[(L ₁ -L ₀ )/L ₀ ]×100...(1). The composite sheet for forming a protective film as described in claim 1 or 2 of the patent application, wherein the aforementioned support sheet further comprises an adhesive layer, the aforementioned substrate, the aforementioned adhesive layer, and the aforementioned thermosetting protective film forming composite sheet. The films are stacked in this order. The composite sheet for forming a protective film according to claim 3, wherein the adhesive layer is non-energy ray curable or energy ray curable. The composite sheet for forming a protective film as described in claim 3 of the patent application, wherein the thickness of the adhesive layer is 3-20 μm. A method for manufacturing a semiconductor wafer with a protective film, comprising the following steps: A laminate is produced by laminating semiconductor wafers on the side of the thermosetting protective film-forming film of the protective film-forming composite sheet described in any one of claims 1 to 5; for the aforementioned laminate The inside of the aforementioned semiconductor wafer is irradiated with laser light to form a modified layer inside the aforementioned semiconductor wafer; the aforementioned thin film for forming a thermosetting protective film of the aforementioned laminate is heated and hardened to form a protective film; and the aforementioned laminate is formed into a protective film. The semiconductor wafer and the thin film for forming a thermosetting protective film or the protective film are divided by performing cold expansion at a temperature lower than normal temperature.

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