TWI904325B - Methods for manufacturing protective film forming films, composites for forming protective films, and wafers with protective films. - Google Patents

Abstract

The present invention is an energy-line hardening protective film forming film (13). The protective film forming film (13) contains an energy-line hardening component (a). After the aforementioned protective film forming film is subjected to energy-line hardening and heated at 260°C for 10 minutes, the weight reduction rate ( _ΔW3 ) of the protective film ( _W3 ) relative to the weight ( _W0 ) of the aforementioned protective film forming film before energy-line hardening is 3.0% or less. After the aforementioned protective film forming film is subjected to energy-line hardening, the gel content of components other than inorganic filler materials is 60% or more.

Description

Methods for manufacturing protective film forming films, composites for forming protective films, and wafers with protective films.

This invention relates to a protective film forming film, a composite sheet for forming a protective film, and a method for manufacturing a wafer with a protective film. This application claims priority based on Japanese Patent Application No. 2021-055013, filed on March 29, 2021, the contents of which are incorporated herein by reference.

Semiconductor wafers or insulator wafers, for example, sometimes have electrical circuits formed on one side (the electrical surface), and thus have protruding electrodes such as bumps on that side (the electrical surface). These wafers are diced into chips, and these protruding electrodes are connected to bonding pads on a circuit substrate, thus mounting the wafers onto the circuit substrate. To prevent cracking and other damage in these wafers or chips, sometimes a protective film is applied to the side opposite the electrical surface (the inner surface).

To form this protective film, a protective film forming film is attached to the inner surface of the wafer. The protective film forming film is deposited on a support sheet to support it, sometimes as a protective film forming composite, and sometimes not deposited on the support sheet. After the protective film forming film is laser-marked, to improve its protective performance, it is hardened by heat or power lines as needed, and the semiconductor wafer is then diced into chips for pickup. Alternatively, the protective film formed by hardening it with heat or power lines can be laser-marked, and the semiconductor wafer can be diced into chips for pickup. Then, the picked-up semiconductor chip with protective film is connected to the bonding pads on the motherboard or other circuit substrates via flip-chip bonding. By heating the circuit substrate to melt the protruding electrodes on the chip with protective film (hereinafter referred to as the reflow step), the electrical connection between the protruding electrodes and the bonding pads on the circuit substrate is strengthened, and the chip is mounted on the circuit substrate.

Among protective film formation films, there exist non-curable protective film formation films that do not possess curing properties and can directly function as protective films in their current state. When using non-curable protective film formation films, since a curing step is unnecessary, wafers with protective films can be manufactured at a low cost through a simplified method. On the other hand, when using curable protective film formation films, since the cured material of the protective film formation film serves as the protective film, it has the advantage of high wafer protection capability. Furthermore, while thermosetting protective film formation films cured by heating require a relatively long heating time, energy line-curable protective film formation films cured by energy line irradiation have the advantage of having a short energy line irradiation time for curing. Therefore, various energy line-curable protective film formation films are being developed (see Patents 1 to 3). [Previous Art Documents] [Patent Documents]

[Patent Document 1] Japanese Patent Application Publication No. 2010-031183. [Patent Document 2] International Publication No. 2017/188197. [Patent Document 3] International Publication No. 2019/082977.

[The problem the invention aims to solve]

In previous methods for manufacturing semiconductor wafers with protective films, including protective film forming films or protective film forming composites, a phenomenon has been observed where low molecular weight substances ooze onto the protective film surface during the reflow step when assembling the picked-up protective film semiconductor wafer onto a circuit substrate. Occurrence onto the protective film surface may impair design and degrade laser markings.

The purpose of this invention is to provide a protective film forming film, a protective film forming composite having the aforementioned protective film forming film, and a method for manufacturing a wafer with a protective film using the aforementioned protective film forming film or the protective film forming composite having a protective film; the aforementioned protective film forming film is an energy line hardening protective film forming film, and the protective film formed by hardening the aforementioned protective film forming film by energy lines suppresses infiltration caused by the reflow step. [Means for solving the problem]

The present invention provides a protective film forming membrane, which is an energy-line hardening protective film forming membrane; the aforementioned protective film forming membrane contains an energy-line hardening component (a); the weight reduction rate (ΔW3) of the protective film after energy-line hardening and heat treatment at 260 _° C for 10 minutes relative to the weight ( _W0 ) of the aforementioned protective film forming membrane before energy-line hardening is 3.0% or less; after energy-line hardening of the aforementioned protective film forming membrane, the gel content of components other than inorganic filler materials is 60% or _more .

In the protective film formed by the present invention, it is preferable that the gloss value (G2) of the protective film after energy line hardening and heat treatment at 260°C for 10 minutes is reduced by less than 30% relative to the gloss value (G1) of the protective film after energy line hardening.

The protective film of the present invention preferably forms a film in which the aforementioned energy line hardening component (a) contains a polyfunctional (meth)acrylate oligomer.

In addition, the present invention provides a composite sheet for forming a protective film, which has a support sheet and a protective film forming film disposed on one side of the support sheet; the aforementioned protective film forming film is the protective film forming film of the present invention.

Furthermore, this invention provides a method for manufacturing a wafer with a protective film, which is used to manufacture a wafer having a protective film disposed on the inner surface of the wafer; comprising the following steps: by attaching the protective film of this invention to the inner surface of the wafer to form a first laminated film consisting of the protective film and the wafer in the thickness direction of these layers; or by attaching the protective film of this invention to the inner surface of the wafer... The protective film forming film in the protective film forming composite sheet is used to fabricate the first laminated composite sheet, which is formed by sequentially stacking the support sheet, the protective film forming film, and the wafer in the thickness direction of these layers. The protective film is formed by energy line hardening of the protective film forming film in the first laminated film or in the first laminated composite sheet, thereby fabricating the protective film and the wafer in the thickness direction of these layers. The second laminated film; or the step of fabricating a second laminated composite film by sequentially laminating the aforementioned support sheet, protective film, and wafer in the thickness direction of these layers; with a dicing blade provided on the protective film side of the aforementioned second laminated film, the aforementioned protective film is cut by dicing the aforementioned wafer in the aforementioned second laminated film to fabricate a third laminated film composed of multiple aforementioned wafers with protective films fixed on the aforementioned dicing blade; or The process involves dividing the wafer in the second laminated composite and cutting the protective film to create a third laminated composite consisting of multiple protective film-bearing wafers fixed on a support sheet; and picking up the protective film-bearing wafers in the third laminated composite by either peeling them off the dicing blade or peeling them off the support sheet. [Invention Benefits]

According to the present invention, a protective film forming film, a protective film forming composite having the aforementioned protective film forming film, and a method for manufacturing a wafer with a protective film using the aforementioned protective film forming film or the protective film forming composite having a protective film are provided; the aforementioned protective film forming film is an energy line hardening protective film forming film, and the protective film formed by hardening the aforementioned protective film forming film by energy lines is suppressed due to the reflow step.

◇Protective Film Forming Membrane One embodiment of the present invention is a line-curing protective film forming membrane; the aforementioned protective film forming membrane contains a line-curing component (a); the weight reduction rate ( _ΔW3 ) of the protective film after line curing and heat treatment at 260°C for 10 minutes relative to the weight ( _W0 ) of the aforementioned protective film forming membrane before line curing is _3.0 % or less; after line curing, the gel content of components other than inorganic filler materials is 60% or more. The protective film forming membrane of this embodiment is used to apply a protective film to a wafer to protect the wafer.

By using the protective film forming film of this embodiment or a protective film forming composite having the protective film forming film, a wafer with a protective film, having a wafer and a protective film disposed on the inner surface of the aforementioned wafer, can be manufactured. The aforementioned wafer with a protective film can be manufactured, for example, by attaching the protective film forming film to the inner surface of the wafer, forming a protective film by curing the protective film forming film, dicing the wafer into wafers, and cutting the protective film along the outer periphery of the wafers.

In this specification, the term "wafer" can include semiconductor wafers made of elemental semiconductors such as silicon, germanium, and selenium, or compound semiconductors such as GaAs, GaP, InP, CdTe, ZnSe, and SiC; and insulating wafers made of insulators such as sapphire, glass, lithium niobate, and lithium tantalum oxide. An electrical circuit is formed on one side of these wafers. In this specification, the side of the wafer with the electrical circuit formed is called the "electrical surface." The side opposite to the electrical surface of the wafer is called the "inner surface." Wafers are diced into chips using methods such as dicing. In this specification, similar to the case of a wafer, the side of the chip where the circuitry is formed is called the "surface," and the side opposite to the surface of the wafer is called the "inner surface." Both the surface of the wafer and the surface of the chip have protruding electrodes such as bumps and pillars. These protruding electrodes are preferably made of solder.

Furthermore, a substrate device can be manufactured using the aforementioned chip with a protective film. In this specification, "substrate device" refers to a device formed by flip-chip bonding a chip with a protective film to bonding pads on a circuit substrate via protruding electrodes on a circuit surface. For example, whenever a semiconductor wafer is used as the wafer, a semiconductor device can be cited as an example of a substrate device.

The protective film forming membrane of this embodiment can be energy-curable, thermosetting, or not thermosetting. When the protective film forming membrane of this embodiment has both energy-curable and thermosetting properties, the energy-curing contribution of the protective film forming membrane to the formation of the protective film is greater than the contribution of thermosetting.

In this manual, the term "energy line" refers to an electromagnetic wave or beam of charged particles possessing energy quanta. Examples of energy lines include ultraviolet rays, radiation, and electron beams. Ultraviolet rays can be emitted by irradiating objects using high-pressure mercury lamps, fusion lamps, xenon lamps, black lights, or LED (Light Emitting Diode) lamps as ultraviolet sources. Electron beams can be emitted by irradiating electron beams generated by electron beam accelerators. In this manual, the term "energy line hardening property" refers to the property of hardening by irradiation with an energy line, while "non-energy line hardening property" refers to the property of not hardening even when irradiated with an energy line. Furthermore, the term "non-hardening property" refers to the property of not hardening by any method, such as heating or irradiation with an energy line.

The curing conditions for forming a protective film by energy line hardening are not particularly limited as long as the degree of hardening is sufficient to allow the protective film to fully perform its function; they can be appropriately selected according to the type of protective film. For example, the illuminance of the energy line during energy line hardening of an energy line-hardening protective film is preferably between 60 mW/ ^cm² and 320 mW/ ^cm² . Furthermore, the light intensity of the energy line during the aforementioned hardening is preferably between 100 mJ/ ^cm² and 1000 mJ/ ^cm² .

Examples of protective film forming films include those containing energy-curing components (a) and those without energy-curing groups (b). The components of the aforementioned protective film forming films will be described in detail below.

The weight reduction rate _ΔW1 of the aforementioned protective film-forming film after heat treatment at 130°C for 2 hours is preferably 1.5% or less, more preferably 1.4% or less, and even more preferably 1.3% or less. Here, the heat treatment conditions of 130°C for 2 hours are the general conditions for thermosetting when the protective film-forming film is thermosetting. By ensuring that the weight reduction rate _ΔW1 is below the aforementioned upper limit, exudation is suppressed when the aforementioned protective film-forming film is heat-treated. For example, using a TG/DTA simultaneous measuring device, the protective film-forming film is heated from 25°C to 130°C at a heating rate of 10°C/min, and then heated at 130°C for 2 hours. The weight reduction rate (ΔW1) (weight %) can be calculated from the weight of the protective film before heating ( _W0 ) and the weight of the protective film after heating ( _W1 ) using the following formula ( ₁ ): _ΔW1 = ( _W0 - _W1 ) / _W0 × 100... (1)

The weight reduction rate _ΔW2 after energy line curing of the aforementioned protective film is preferably 0.30% or less, more preferably 0.25% or less, and even more preferably 0.20% or less. Here, the conditions for energy line curing are not limited as long as the protective film formation film is sufficiently energy line cured.

Using a UV irradiation device, the protective film was irradiated twice with ultraviolet light at a wavelength of 365 nm under conditions of illuminance of 200 mW/ ^cm² and light intensity ^of 300 mJ/cm². The weight reduction rate ( _ΔW² ) (weight %) can be calculated from the weight of the protective film before energy line curing ( _W₀ ) and the weight of the protective film after energy line curing ( _W₂ ) using the following formula (2): _ΔW² = ( _W₀ - _W₂ ) / _W₀ × 100... (2)

The weight reduction rate ( _ΔW3 ) of the aforementioned protective film after energy line curing and heat treatment at 260°C for 10 minutes is 3.0% or less. With a weight reduction rate ( _ΔW3 ) of 3.0% or less, the exudation caused by the reflow step in the protective film formed by energy line curing is suppressed. It is believed that as long as the weight reduction rate ( _ΔW3 ) of the protective film after energy line curing and heat treatment at 260°C for 10 minutes is small, less low-molecular-weight material will exudate from the surface of the protective film during the reflow step when assembling the semiconductor wafer with the protective film onto the circuit substrate.

Here, the conditions for energy line curing are not limited, as long as the protective film formation is sufficiently heat-cured. For example, irradiation with 200 mW/ ^cm² illuminance and 300 mJ/ ^cm² light intensity twice with 365 nm wavelength ultraviolet light is sufficient. Energy line curing treatment can be performed, for example, using the RAD2000 UV irradiation device manufactured by Lintec Corporation. For instance, using a TG/DTA simultaneous measurement device, the UV-irradiated protective film can be heated from 25°C to 260°C at a heating rate of 10°C/min, and then heated at 260°C for 10 minutes. The weight reduction rate ( _ΔW3 ) (weight %) can be calculated using the following formula ( ₃ ): _ΔW3 = ( _{W0 - W3} ) / _W0 × 100.

The weight loss rate ( _ΔW3 ) is preferably below 2.8%, more preferably below 2.6%, and even more preferably below 2.4%.

After the aforementioned protective film is line-cured, the gel content of components other than the inorganic filler is 60% or more. By achieving this gel content of 60% or more, leakage during the reflow step is suppressed in the protective film formed by line-curing the aforementioned protective film. It is believed that the higher the gel content of components other than the inorganic filler, the less low-molecular-weight substances will leak onto the surface of the protective film during the reflow step when mounting the semiconductor chip with the protective film onto the circuit board. Here, the gel content of components other than the inorganic filler refers to the degree of gelation of components other than the inorganic filler in the protective film after line-curing the protective film. In the protective film formation process, inorganic fillers are excluded because they do not contribute to the gelation of resin components caused by energy line hardening.

Next, the method for determining the gel content of components other than the inorganic filler material is explained. The protective film forming membrane is irradiated twice with ultraviolet light at a wavelength of 365 nm under conditions of 200 mW/ ^cm² illuminance and 300 mJ/ ^cm² light intensity. For example, a test piece is made by covering the ultraviolet-irradiated protective film with a nylon mesh (mesh size 200) and stapled together. The mass _M1 of the test piece, the mass _M2 of the nylon mesh, and the mass _M3 of the stapler needle are weighed using a precision balance. Additionally, the mass _M4 of the inorganic filler material (d) in the protective film forming membrane test piece is pre-calculated. The mass _M4 of the inorganic filler material (d) can be calculated from the amount prepared during the production of the protective film forming membrane. Then, after immersing the test piece in ethyl acetate at 25°C for 48 hours, the insoluble matter of the protective film after UV irradiation, the nylon mesh, and the stapler needle were removed and dried. Then, the mass _M5 of the immersed and dried test piece was weighed using a precision balance. Furthermore, the gel fraction of components other than the inorganic filler material can be calculated using the following formula (4): ΔG＝( _M5 － _M2 － _M3 － _M4 )／( _M1 － _M2 － _M3 － _M4 )×100・・・(4)

Here, ( _M1 - _M2 - _M3 - _M4 ) represents the mass of the components other than the inorganic filler material in the protective film after the energy line is hardened, and ( _M5 - _M2 - _M3 - _M4 ) represents the mass of the component that is insoluble in ethyl acetate among the components other than the inorganic filler material in the protective film after the energy line is hardened.

Preferably, the gloss value (G2) of the protective film after energy line curing and heat treatment at 260°C for 10 minutes is reduced by 30% or less, more preferably by 28% or less, and even more preferably by 26% or less. By reducing the gloss value by less than the aforementioned upper limit, surface penetration of the protective film formed by energy line curing of the protective film is suppressed during the reflow step when mounting it onto a circuit board.

The aforementioned gloss values (G1) and (G2) were measured when the protective film was formed by energy line hardening of the protective film on the wafer of the protected object. The gloss value of the protective film was measured at an incident angle of 60° from the protective film side.

More specifically, the protective film is formed by energy line curing of the protective film forming film in the first laminated film, thereby fabricating the protective film and a second laminated film formed by stacking the wafer in the thickness direction of these layers. The gloss value (G1) of the protective film is measured using a gloss meter at an incident angle of 60° from the protective film side of the second laminated film. Then, the second laminated film is heated to 260°C for 10 minutes, and the gloss value (G2) of the heated protective film is measured under the same conditions as the gloss value (G1) before heating. Furthermore, the protective film is formed by energy line curing of the protective film in the first laminated composite, thereby creating a second laminated composite consisting of the support sheet, the protective film, and the wafer sequentially laminated along the thickness direction of these layers. The support sheet is peeled off from the second laminated composite to create a test piece. Using a gloss meter, the gloss value (G1) of the protective film is measured at an incident angle of 60° from the protective film side. The test piece is then heated to 260°C for 10 minutes, and the gloss value (G2) of the heated protective film is measured under the same conditions as the measurement of the gloss value (G1) before heating.

The reduction rate (%) of the gloss value of the protective film after heat treatment at 260℃ for 10 minutes can be calculated using the following formula (5): Reduction rate (%) of gloss value = (G1 - G2) / G1 × 100...(5)

The aforementioned protective film forming film preferably satisfies the storage elastic modulus E' as shown below. That is, a test piece of a protective film forming film with a thickness of 200 μm (sometimes referred to as "protective film forming film test piece" in this specification) which is a multi-layered stack of protective film forming films is held at two locations with a spacing of 20 mm. Under the test conditions of stretching at a frequency of 11 Hz and a heating rate of 3 °C/min, the storage elastic modulus E' of the aforementioned protective film forming film test piece is measured in a temperature range from -10 °C to 140 °C. The storage elastic modulus E' ₇₀ of the aforementioned protective film forming film test piece at 70 °C is preferably 30 MPa or less, more preferably 10 MPa or less, and for example, it can also be 5 MPa or less. By ensuring that the storage elastic modulus E' ₇₀ is below the aforementioned upper limit, it is easier to attach the protective film to the substrate (wafer). There is no particular limitation on the lower limit of the aforementioned storage elastic modulus E' _70. For example, protective film forming films with a storage elastic modulus E' ₇₀ of 0.5 MPa or higher can be more easily manufactured, resulting in protective films with better properties.

In this manual, not limited to the aforementioned test piece, unless otherwise specified, "thickness" refers to the average thickness measured at 5 randomly selected locations on the object, which can be obtained using a constant pressure thickness gauge according to JISK7130.

The length of the aforementioned protective film-forming test piece in the stretching direction of the aforementioned stretching mode is not particularly limited, as long as it does not impair the accuracy of the measurement of the storage elastic modulus E’, but it is preferably 30 mm or more. When measuring the storage elastic modulus E’ of the aforementioned protective film-forming test piece, it is preferable to subject the test piece to constant-rate heating. When measuring the storage elastic modulus E’ of the aforementioned protective film-forming test piece, it is preferable that the amplitude is 5 μm.

The aforementioned protective film forming the energy line hardened protective film preferably satisfies the following condition regarding the storage elastic modulus E'. That is, as a multi-layered protective film stack, for a stack with a thickness of 50 μm, illuminance of 200 mW/ ^cm² and light intensity of 300 mJ/cm² are applied from both sides. Under conditions ² , the protective film is irradiated twice with ultraviolet light of wavelength 365nm to form a film hardening, thus creating a protective film test piece (sometimes referred to as "protective film test piece" in this specification). The aforementioned protective film test piece is held at a distance of 20mm between two locations. Under the measurement conditions of stretching mode at a frequency of 11Hz and heating rate of 3℃/min between the two locations, the storage elastic modulus E' of the aforementioned protective film test piece is measured in a temperature range from 0℃ to 300℃. The storage elastic modulus E' of the aforementioned protective film test piece at ₁₃₀ ℃ is preferably 5MPa or more, more preferably 8MPa or more, and even more preferably 10MPa or more. By ensuring that the storage elastic modulus E' ₁₃₀ is above the aforementioned lower limit, the protective film's protective effect on the adhered object (wafer) is further enhanced. There is no particular limitation on the upper limit of the aforementioned storage elastic modulus E' _130. For example, protective films with a storage elastic modulus E' ₁₃₀ below 3000 MPa are easier to manufacture and possess better properties.

The length of the aforementioned protective film test piece in the stretching direction of the aforementioned stretching mode is not particularly limited, as long as it does not impair the measurement accuracy of the stored elastic modulus E’, but is preferably 30 mm or more. When measuring the stored elastic modulus E’ of the aforementioned protective film test piece, it is preferable to subject the test piece to constant-rate heating. When measuring the stored elastic modulus E’ of the aforementioned protective film test piece, it is preferable that the amplitude is 5 μm.

The storage elastic modulus E' of the protective film forming test piece and the protective film test piece (in other words, the storage elastic modulus E' of the protective film forming membrane and the protective film) can be reduced, for example, by increasing the content of low molecular weight polymer components, such as the energy line hardening component (a) described later, in the protective film forming membrane. Additionally, increasing the content of the inorganic filler material (d) described later in the protective film forming membrane can also reduce the storage elastic modulus E' of the protective film forming membrane test piece. On the other hand, the storage elastic modulus E' of the protective film test piece can be increased by increasing the content of the energy line hardening component (a) described later in the protective film forming membrane. Additionally, reducing the content of the inorganic filler material (d) described later in the protective film formation process can increase the storage elastic modulus E' of the protective film test piece.

The protective film can be composed of a single layer or multiple layers, either two or more. When the protective film is composed of multiple layers, these layers can be the same or different from each other, and there is no particular limitation on the combination of these layers.

This instruction manual is not limited to the formation of a protective film. The phrase "multiple layers may be the same or different" means that "all layers may be the same, all layers may be different, or only some layers may be the same." Furthermore, the phrase "multiple layers are different" means that "at least one of the constituent materials and thicknesses of each layer is different."

The thickness of the protective film is preferably from 1 μm to 100 μm, more preferably from 3 μm to 80 μm, and even more preferably from 5 μm to 60 μm. By ensuring the thickness of the protective film is above the aforementioned lower limit, a protective film with higher protective capabilities can be formed. By ensuring the thickness of the protective film is below the aforementioned upper limit, excessive thickness of the wafer with the protective film can be avoided. Here, "thickness of the protective film" refers to the overall thickness of the protective film, such as the thickness of a multi-layered protective film, meaning the total thickness of all layers constituting the protective film.

[Composition for Protective Film Formation] A protective film can be formed using an energy line curing protective film forming composition (sometimes referred to as "protective film forming composition" in this specification) containing a material constituting a protective film forming film. For example, a protective film forming film can be formed by applying the aforementioned protective film forming composition to a surface to which it is to be formed and drying it as needed. The ratio of the components in the protective film forming composition that do not vaporize at room temperature is generally the same as the ratio of the aforementioned components in the protective film forming film. In this specification, "room temperature" refers to a temperature that is neither particularly cold nor particularly hot, i.e., a normal temperature, such as temperatures from 18°C to 28°C.

In the protective film forming film, the total content of one or more of the components described below (described later) in the protective film forming film does not exceed 100% by mass relative to the total mass of the protective film forming film. Similarly, in the protective film forming composition, the total content of one or more of the components described below (described later) in the protective film forming composition does not exceed 100% by mass relative to the total mass of the protective film forming composition.

The protective film can be applied using known methods, such as the following coating machines: air knife coating machine, scraper coating machine, rod coating machine, gravure coating machine, roller coating machine, roller knife coating machine, curtain coating machine, mold coating machine, knife coating machine, screen coating machine, Meyer rod coating machine, touch coating machine, etc.

There are no particular limitations on the drying conditions of the protective film forming composition. However, when the protective film forming composition contains the solvent described later, it is preferable to perform heat drying. Furthermore, the protective film forming composition containing the solvent is preferably heat dried at 70°C to 130°C for 10 seconds to 5 minutes. However, the heat-curable protective film forming composition is preferably heat-dried in a manner that neither the composition itself nor the heat-curable protective film formed by the composition will heat-cur.

[Composition for Forming a Line-Curing Protective Film (IV)] Preferred compositions for forming a protective film include, for example, a composition (IV) for forming a line-curing protective film containing the aforementioned line-curing component (a), the aforementioned acrylic resin without line-curing groups (b), and the aforementioned inorganic filler material (d) (sometimes referred to as "Composition (IV)" in this specification).

[Energy-Curable Component (a)] Energy-curable component (a) is a component that is cured by irradiation with energy rays. It imparts membrane-forming properties or flexibility to the protective film and is also used to form a hard protective film after curing. The protective film forming membrane, by containing energy-curable component (a), can form a protective film with excellent properties. In the protective film forming membrane, energy-curable component (a) is preferably uncured, more preferably adhesive, and even more preferably uncured and adhesive.

Examples of energy line hardening components (a) include polymers (a1) having energy line hardening groups and a weight average molecular weight of 80,000 to 2,000,000, and compounds (a2) having energy line hardening groups and a molecular weight of 100 to 80,000. The aforementioned polymer (a1) may be at least partially crosslinked using a crosslinking agent, or it may not be crosslinked.

[Polymers (a1) having energy-line hardening groups and a weight-average molecular weight of 80,000 to 2,000,000] An example of a polymer (a1) having energy-line hardening groups and a weight-average molecular weight of 80,000 to 2,000,000 is acrylic resin (a1-1), which is formed by reacting an acrylic polymer (a11) with an energy-line hardening compound (a12). The acrylic polymer (a11) has functional groups that can react with groups found in other compounds, and the energy-line hardening compound (a12) has energy-line hardening groups such as groups that react with the aforementioned functional groups and energy-line hardening double bonds.

The aforementioned functional groups that can react with groups found in other compounds include, for example, hydroxyl, carboxyl, amino, substituted amino groups (groups with a structure in which one or two hydrogen atoms of an amino group are replaced by groups other than hydrogen atoms), epoxy groups, etc. However, for the purpose of preventing circuit corrosion of wafers or chips, the aforementioned functional groups are preferably groups other than carboxyl. Of these, the aforementioned functional group is preferably hydroxyl.

• Functionalized Acrylic Polymer (a11) The aforementioned functionalized acrylic polymer (a11) can be exemplified by copolymers formed by copolymerizing the aforementioned functionalized acrylic monomer with the aforementioned non-functionalized acrylic monomer, or copolymers formed by copolymerizing monomers other than acrylic monomers (non-acrylic monomers). Furthermore, the aforementioned acrylic polymer (a11) can be a random copolymer or a block copolymer, and known methods can be used for polymerization.

Examples of acrylic monomers with functional groups include monomers containing hydroxyl groups, monomers containing carboxyl groups, monomers containing amino groups, monomers containing substituted amino groups, and monomers containing epoxy groups.

Examples of hydroxyl-containing monomers mentioned above include: hydroxymethyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxybutyl methacrylate, 4-hydroxybutyl methacrylate, and other hydroxyalkyl methacrylates; and non-(meth)acrylic acid unsaturated alcohols (unsaturated alcohols without a (meth)acrylic acid backbone) such as vinyl alcohol and allyl alcohol.

Examples of the aforementioned carboxyl-containing monomers include: (meth)acrylic acid, butenoic acid, and other ethylene-unsaturated monocarboxylic acids (monocarboxylic acids with ethylene-unsaturated bonds); fumaric acid, icosinic acid, maleic acid, carboxyconic acid, and other ethylene-unsaturated dicarboxylic acids (dicarboxylic acids with ethylene-unsaturated bonds); anhydrides of the aforementioned ethylene-unsaturated dicarboxylic acids; and (meth)acrylic acid carboxyl alkyl esters such as 2-carboxyethyl methacrylate.

The aforementioned acrylic monomers with functional groups are preferably monomers containing hydroxyl groups.

The acrylic monomers with functional groups that constitute the aforementioned acrylic polymer (a11) may be only one type or two or more types. In the case of two or more types, the combination and ratio of these acrylic monomers can be arbitrarily selected.

Examples of acrylic monomers that do not possess functional groups include: methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, dibutyl methacrylate, terbutyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl methacrylate, 2-ethylhexyl methacrylate, isooctyl methacrylate, n-octyl methacrylate, n-nonyl methacrylate, and isononyl methacrylate. Alkyl esters, such as decyl methacrylate, undecyl methacrylate, dodecyl methacrylate (laurate methacrylate), tridecyl methacrylate, tetradecyl methacrylate (myristyl methacrylate), pentadecyl methacrylate, hexadecyl methacrylate (palmitoyl methacrylate), heptadecanyl methacrylate, and octadecyl methacrylate (stearyl methacrylate), are alkyl esters in which the alkyl group has a chain structure with 1 to 18 carbon atoms.

In addition, examples of acrylic monomers that do not have functional groups include: methoxymethyl methacrylate, methoxyethyl methacrylate, ethoxymethyl methacrylate, ethoxyethyl methacrylate, and other alkoxyalkyl (meth)acrylates; aromatic (meth)acrylates including aryl (meth)acrylates such as phenyl (meth)acrylate; non-crosslinked (meth)acrylamide and its derivatives; and non-crosslinked tertiary amino (meth)acrylates such as N,N-dimethylaminoethyl (meth)acrylate and N,N-dimethylaminopropyl (meth)acrylate.

The acrylic monomers that do not have functional groups that constitute the aforementioned acrylic polymer (a11) may be only one type or two or more types. In the case of two or more types, the combination and ratio of these acrylic monomers can be arbitrarily selected.

Examples of the aforementioned non-acrylic monomers include, for example, olefins such as ethylene and norbornene; vinyl acetate; and styrene. The aforementioned non-acrylic monomers constituting the aforementioned acrylic polymer (a11) 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 non-acrylic monomers can be arbitrarily chosen.

In the aforementioned acrylic polymer (a11), the proportion (content) of the constituent unit derived from the aforementioned functional acrylic monomer relative to the total amount of constituent units constituting the acrylic polymer (a11) is preferably 0.1% to 50% by mass, more preferably 1% to 40% by mass, and even more preferably 3% to 30% by mass. By using the aforementioned proportion within this range, the content of the energy-curing groups in the aforementioned acrylic resin (a1-1) obtained by copolymerizing the aforementioned acrylic polymer (a11) and the aforementioned energy-curing compound (a12) can be adjusted to a range that results in a better degree of curing of the protective film.

The acrylic polymer (a11) constituting the aforementioned acrylic resin (a1-1) may be only one type or may be two or more types. In the case of two or more types, the combination and ratio of these acrylic polymers (a11) can be arbitrarily selected.

The ratio of acrylic resin (a1-1) content in the protective film to the total mass of the protective film is preferably 1% to 70% by mass, more preferably 5% to 60% by mass, and even more preferably 10% to 50% by mass.

• Energy Line Curing Compound (a12) The aforementioned energy line curing compound (a12) preferably has one or more groups selected from the group consisting of isocyanate groups, epoxy groups, and carboxyl groups as functional groups that can react with the aforementioned acrylic polymer (a11), and more preferably has an isocyanate group as such a group. When the aforementioned energy line curing compound (a12) has, for example, an isocyanate group as such a group, the isocyanate group readily reacts with the hydroxyl group of the acrylic polymer (a11) having a hydroxyl group as such a functional group.

The number of the aforementioned energy-line hardening groups in one molecule of the energy-line hardening compound (a12) is not particularly limited; for example, it can be appropriately selected considering physical properties such as the shrinkage rate required for the intended protective film. For example, it is preferable that one to five of the aforementioned energy-line hardening groups are present in one molecule of the aforementioned energy-line hardening compound (a12), more preferably one to three.

Examples of the aforementioned energy line hardening compounds (a12) include: 2-methacryloxyethyl isocyanate, m-isopropenyl-α,α-dimethylbenzyl isocyanate, methacryloxyisocyanate, allyl isocyanate, and 1,1-(bisacryloxymethyl)ethyl isocyanate; acrylonitrile monoisocyanate compounds obtained by reacting diisocyanate compounds or polyisocyanate compounds with hydroxyethyl (meth)acrylate; and acrylonitrile monoisocyanate compounds obtained by reacting diisocyanate compounds or polyisocyanate compounds, polyol compounds, and hydroxyethyl (meth)acrylate. Of these, the aforementioned energy line hardening compound (a12) is preferably 2-methylacryloxyethyl isocyanate.

The energy-curing compound (a12) that constitutes the aforementioned acrylic resin (a1-1) may be only one type or may be two or more types. In the case of two or more types, the combination and ratio of these energy-curing compounds (a12) may be arbitrarily selected.

In the aforementioned acrylic resin (a1-1), the content of the energy-curing group derived from the aforementioned energy-curing compound (a12) relative to the content of the aforementioned functional groups derived from the aforementioned acrylic polymer (a11) is preferably 20 mol% to 120 mol%, more preferably 35 mol% to 100 mol%, and even more preferably 50 mol% to 100 mol%. With the aforementioned content within this range, the adhesion of the cured protective film becomes greater. Furthermore, when the aforementioned energy-curing compound (a12) is a single-functional compound (having one of the aforementioned groups in one molecule), the upper limit of the aforementioned content ratio is 100 mol%, but when the aforementioned energy-curing compound (a12) is a multifunctional compound (having two or more of the aforementioned groups in one molecule), the upper limit of the aforementioned content ratio sometimes exceeds 100 mol.

The aforementioned polymer (a1) preferably has a weight-average molecular weight (Mw) of 100,000 to 2,000,000, more preferably 300,000 to 1,500,000. Here, "weight-average molecular weight" refers to the term as explained above.

The aforementioned polymer (a1) contained in the composition (IV) and the protective film forming film may be only one type or two or more types. In the case of two or more types, the combination and ratio of these polymers (a1) can be arbitrarily selected.

[Compounds having an energy-line hardening group and a molecular weight of 100 to 80,000 (a2)] The aforementioned energy-line hardening group in compounds (a2) having an energy-line hardening group and a molecular weight of 100 to 80,000 can include groups containing energy-line hardening double bonds. Preferred examples of such groups include (meth)acrylic acid and vinyl groups.

The aforementioned compound (a2) is not particularly limited as long as it meets the above conditions. Examples include: low molecular weight compounds with energy line hardening groups, epoxy resins with energy line hardening groups, and phenolic resins with energy line hardening groups.

Among the aforementioned compound (a2), the low molecular weight compound having an energy line hardening group can be, for example, a multifunctional monomer or oligomer, and preferably an acrylate compound having a (meth)acrylic group.

As for the aforementioned acrylate compounds, examples include multifunctional monomers or oligomers, but preferably multifunctional acrylate compounds having two or three or more (meth)acrylic groups in one molecule. Examples of the aforementioned multifunctional acrylate compounds include: 2-hydroxy-3-(meth)acryloxypropyl methacrylate, polyethylene glycol di(meth)acrylate, propoxylated ethoxylated bisphenol A di(meth)acrylate, 2,2-bis[4-((meth)acryloxypolyethoxy)phenyl]propane, ethoxylated bisphenol A di(meth)acrylate, 2,2-bis[4-((meth)acryloxydiethoxy)phenyl]propane, 9,9-bis[4-(2-(meth)acryloxyethoxy)phenyl]propane, 2,2-bis[4-((meth)acryloxypoly)propane]propane, and 2,2-bis[4-((meth)acryloxypoly]propane]propane. [Oxyphenyl]propane, tricyclodecanediethanol di(meth)acrylate (also known as tricyclodecanedihydroxymethyldi(meth)acrylate), 1,10-decanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, 2,2-bis[ 4-((meth)acryloxyethoxy)phenyl]propane, neopentyl glycol di(meth)acrylate, ethoxylated polypropylene glycol di(meth)acrylate, 2-hydroxy-1,3-di(meth)acryloxypropane and other difunctional (meth)acrylates (meth)acrylates having two (meth)acrylyl groups in one molecule); tris(2-(meth)acryloxyethyl) isocyanurate, ε-caprolactone-modified tris(2-(meth)acryloxyethyl) isocyanurate, ethoxylated glycerol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, trihydroxymethylpropane Tri(meth)acrylate, di-trimethylpropane tetra(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol poly(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and other polyfunctional (meth)acrylates (meth)acrylates having three or more (meth)acrylic groups in one molecule); polyfunctional (meth)acrylate oligomers such as polyfunctional (meth)acrylate aminocarbamate oligomers (meth)acrylate oligomers having two or three or more (meth)acrylic groups in one molecule), etc.

In the aforementioned compound (a2), the epoxy resin having an energy-curing group or the phenolic resin having an energy-curing group may be, for example, the resin described in paragraph 0043 of Japanese Patent Application Publication No. 2013-194102. Such a resin is also equivalent to the resin constituting the thermosetting component described later, but is regarded as the aforementioned compound (a2) in composition (IV).

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

The composition (IV) and the protective film forming film may contain only one or more of the aforementioned compounds (a2). In the case of two or more compounds, the combination and ratio of these compounds (a2) can be arbitrarily selected.

As the energy-curing component (a) in the protective film forming film, it preferably contains the aforementioned compound (a2), more preferably a polyfunctional acrylate compound having two or three or more (meth)acrylic groups in one molecule, and even more preferably a polyfunctional (meth)acrylate aminocarboxylate oligomer. The protective film forming film containing this energy-curing component (a), when cured by energy-ray irradiation, has good protective ability and flexibility, exhibiting particularly excellent properties.

When the composition (IV) and the protective film forming film contain an energy line hardening component (a), the content of the energy line hardening component (a) in the composition (IV) and the protective film forming film relative to the content of the acrylic resin (b) is preferably 100 parts by weight to 310 parts by weight, more preferably 130 parts by weight to 280 parts by weight, for example, it can also be 130 parts by weight to 200 parts by weight, or 210 parts by weight to 280 parts by weight.

In composition (IV), the content ratio of the energy-curing component (a) relative to the total content of all components other than the solvent (i.e., the ratio of the content of the energy-curing component (a) in the protective film to the total mass of the protective film) is preferably 12% to 31% by mass, more preferably 14% to 28% by mass, and even more preferably 16% to 25% by mass. By having the aforementioned content ratio of the energy-curing component (a) (i.e., the ratio of the aforementioned energy-curing component (a)) at or above the aforementioned lower limit value, the energy-curing property of the aforementioned protective film becomes better, and the seepage caused by the reflux step in the protective film formed by curing the aforementioned protective film by energy lines is further suppressed. By ensuring that the content ratio of the aforementioned energy line hardening component (a) is below the aforementioned upper limit, the desired protective film can be easily prepared.

[Acrylic resin (b) without energy-line hardening groups] The aforementioned protective film forming film preferably contains acrylic resin (b) without energy-line hardening groups (sometimes referred to as "acrylic resin (b)" in this specification).

The aforementioned acrylic resin (b) is a component that imparts membrane-forming properties to the protective film.

The aforementioned acrylic resin (b) can be a known polymer, such as a homopolymer of one acrylic monomer, a copolymer of two or more acrylic monomers, or a copolymer of one or more acrylic monomers with one or more monomers other than acrylic monomers (non-acrylic monomers).

Acrylic resin (b) may be crosslinked at least partially by a crosslinking agent, or it may not be crosslinked.

Examples of acrylic monomers constituting acrylic resin (b) include: alkyl (meth)acrylates, (meth)acrylates with a cyclic skeleton but no functional group, (meth)acrylates containing glycidyl groups, (meth)acrylates containing hydroxyl groups, (meth)acrylates containing substituted amino groups, (meth)acrylates containing carboxyl groups, and (meth)acrylates containing amino groups; (meth)acrylamide; and (meth)acrylamide derivatives such as 4-(meth)acrylamide-formin. Here, "substituted amino group" refers to a structural group in which one or two hydrogen atoms of an amino group are replaced by a group other than a hydrogen atom. Here, the term "functional group" refers to a group that can react with other groups such as glycerol, hydroxyl, substituted amino, carboxyl, and amino groups (reactive functional groups).

In this manual, the term "(meth)acrylic acid" includes both "acrylic acid" and "methacrylic acid". Similar terms are used interchangeably; for example, the term "(meth)acrylate" includes both "acrylate" and "methacrylate", and the term "(meth)acryl" includes both "acryl" and "methacryl".

In this specification, when a specific compound has a structure in which one or more hydrogen atoms are replaced by groups other than hydrogen atoms, such a compound with a substituted structure is called a "derivative" of the aforementioned specific compound. In this specification, the term "group" refers not only to an atomic group composed of multiple atoms, but also to a single atom.

Examples of alkyl methacrylates that do not possess the aforementioned functional groups and cyclic skeletons include: methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, dibutyl methacrylate, tributyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl methacrylate, 2-ethylhexyl methacrylate, isooctyl methacrylate, n-octyl methacrylate, n-nonyl methacrylate, and propyl methacrylate. Alkyl esters, such as isononyl acrylate, decyl acrylate, undecyl acrylate, dodecyl acrylate (laurate), tridecyl acrylate, tetradecyl acrylate (myristyl acrylate), pentadecyl acrylate, hexadecyl acrylate (palmitoyl acrylate), heptadecanyl acrylate, and octadecyl acrylate (stearyl acrylate), are alkyl esters in which the alkyl group has a chain structure with 1 to 18 carbon atoms.

Examples of (meth)acrylates that are cyclic esters but lack the aforementioned functional groups include: isobornyl (meth)acrylate, dicyclopentyl (meth)acrylate, and other cycloalkyl (meth)acrylates; benzyl (meth)acrylate, and other aralkyl (meth)acrylates; dicyclopentenyl (meth)acrylate, and other cycloalkyl (meth)acrylates; dicyclopentenyl (meth)acrylate, and other cycloalkyl (meth)acrylates.

Examples of the aforementioned (meth)acrylates containing glycidyl groups include glycidyl methacrylate. Examples of the aforementioned (meth)acrylates containing hydroxyl groups include alkyl (meth)acrylates lacking the aforementioned functional groups and cyclic skeletons, and (meth)acrylates lacking the aforementioned functional groups but possessing a cyclic skeleton, wherein one or more hydrogen atoms are replaced by hydroxyl groups. Preferred examples of the aforementioned (meth)acrylates containing hydroxyl groups include hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. Examples of the aforementioned (meth)acrylates containing substituted amino groups include N-methylaminoethyl (meth)acrylate.

As constituents of acrylic resin (b), the aforementioned non-acrylic monomers include, for example, olefins such as ethylene and norbornene; vinyl acetate; styrene, etc.

Acrylic resin (b) that is at least partially crosslinked using a crosslinking agent, for example, is an acrylic resin (b) formed by reacting functional groups of acrylic resin (b) with a crosslinking agent. The aforementioned functional groups can be appropriately selected according to the type of crosslinking agent, and there is no particular limitation. For example, when the crosslinking agent is a polyisocyanate compound, hydroxyl, carboxyl, and amino groups can be listed as the aforementioned functional groups, among which hydroxyl groups, which have high reactivity with isocyanate groups, are preferred. Furthermore, when the crosslinking agent is an epoxy compound, carboxyl and amino groups can be listed as the aforementioned functional groups, among which carboxyl groups, which have high reactivity with epoxy groups, are preferred. However, in terms of preventing circuit corrosion on wafers or chips, it is preferable that the aforementioned functional groups are groups other than carboxyl groups.

As an example of the aforementioned acrylic resin (b) having a functional group, an acrylic resin (b) obtained by polymerizing at least the aforementioned functionalized monomers can be listed. More specifically, an example of the aforementioned acrylic resin (b) having a functional group can be listed as an acrylic resin (b) obtained by polymerizing one or more monomers selected from the group consisting of the aforementioned (meth)acrylates containing glycidyl groups, the aforementioned (meth)acrylates containing hydroxyl groups, the aforementioned (meth)acrylates containing substituted amino groups, the aforementioned (meth)acrylates containing carboxyl groups, the aforementioned (meth)acrylates containing amino groups, and monomers having a structure in which one or more hydrogen atoms in the aforementioned non-acrylic monomers are replaced by the aforementioned functional groups.

In the aforementioned acrylic resin (b), the proportion (content) of the constituent units derived from functional monomers relative to the total amount of constituent units constituting the polymer (b) is preferably 1% to 20% by mass, more preferably 2% to 10% by mass. With the aforementioned proportion within this range, the degree of crosslinking in the acrylic resin (b) becomes even more desirable.

Regarding the further suppression of seepage due to the reflux step, the weight average molecular weight (Mw) of the acrylic resin (b) is preferably 10,000 or more, more preferably 20,000 or more, and even more preferably 40,000 or more. Regarding the improved film-forming properties of component (IV), the weight average molecular weight (Mw) of the acrylic resin (b) is preferably 10,000 to 2,000,000, more preferably 100,000 to 1,500,000.

Unless otherwise specified, the "weight average molecular weight" in this manual refers to the polystyrene conversion value determined by gel permeation chromatography (GPC).

The acrylic resin (b) contained in the composition (IV) and the aforementioned protective film forming film may be only one type or two or more types. In the case of two or more types, the combination and ratio of these polymers (b) may be arbitrarily selected.

In composition (IV), the ratio of the content of acrylic resin (b) to the total content of all components other than the solvent (i.e., the ratio of the content of acrylic resin (b) in the protective film to the total mass of the protective film) is preferably 8% by mass or more, more preferably 10% by mass or more, and for example, it may also be any one of 12% by mass or more and 14% by mass or more.

In composition (IV), there is no particular upper limit to the ratio of the content of acrylic resin (b) to the total content of all components other than the solvent (i.e., the ratio of the content of acrylic resin (b) in the protective film to the total mass of the protective film). Regarding the aspect where the protective film can achieve a balanced performance of its properties in inhibiting seepage caused by the reflux step and other properties, the aforementioned upper limit may also be 27% by mass or less, preferably 25% by mass or less, more preferably 23% by mass or less, and even more preferably 21% by mass or less.

In composition (IV), the ratio of the acrylic resin (b) content to the total content of all components other than the solvent (i.e., the ratio of the acrylic resin (b) content in the protective film to the total mass of the protective film) can be appropriately adjusted within any combination of the aforementioned lower and upper limits. For example, in one embodiment, the aforementioned ratio is preferably 8% to 27% by mass, more preferably 10% to 25% by mass, and can also be 12% to 23% by mass, and any one of 14% to 21% by mass.

When the composition (IV) and the protective film forming film contain energy line curing component (a) and acrylic resin (b), the content of energy line curing component (a) in the composition (IV) and the protective film forming film is 100 parts by weight, preferably 70 parts by weight to 310 parts by weight, more preferably 80 parts by weight to 280 parts by weight, and even more preferably 85 parts by weight to 250 parts by weight.

In composition (IV), the ratio of the total content of the energy line curing component (a) and acrylic resin (b) to the total content of all components other than the solvent (i.e., the ratio of the total content of the energy line curing component (a) and acrylic resin (b) in the protective film to the total mass of the protective film) is preferably 10% to 60% by mass, for example, it can also be any one of 20% to 50% by mass and 30% to 45% by mass. By using the aforementioned ratio within this range, the effectiveness brought about by using the energy line curing component (a) and acrylic resin (b) can be further improved.

[Other Components] Without impairing the effectiveness of the invention, the composition (IV) and the protective film forming film may also contain other components not equivalent to either the energy-curing component (a) or the acrylic resin (b). Examples of the aforementioned other components include: photopolymerization initiator (c); inorganic filler (d); coupling agent (e); crosslinking agent (f); colorant (g); thermosetting component (h); general additive (z); and polymers (b0) not equivalent to the acrylic resin (b) that do not have energy-curing groups (sometimes referred to in this specification as "other polymers (b0) without energy-curing groups" or "polymer (b0)").

(Photopolymerization Initiator (c)) When both the composition (IV) and the protective film forming film contain the photopolymerization initiator (c), the polymerization (curing) reaction of the energy line hardening component (a) can proceed efficiently.

Examples of photopolymerization initiators include: benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, methyl benzoate, benzoin dimethyl ketone, and other benzoin compounds; acetophenone compounds such as 2-hydroxy-2-methyl-1-phenylpropane-1-one, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropane)benzyl)phenyl)-2-methylpropane-1-one, and 2-(dimethylamino)-1-(4-mofolinphenyl)-2-benzyl-1-butanone; and bis(2,4,6-trimethylammonium trioxide). Phosphine oxide compounds such as methylbenzoyl(phenyl)phosphine oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide; sulfide compounds such as benzylphenyl sulfide and tetramethylthiuram monosulfide; α-keto alcohol compounds such as 1-hydroxycyclohexylphenyl ketone; azo compounds such as azobisisobutyronitrile; titanium eccentricate compounds such as titanium eccentricate; thiotonone compounds such as thiotonone; peroxide compounds; diacetyl compounds such as diacetyl; benzohexane; dibenzohexane; benzophenone; 2,4-diethylthiotonone; 1,2-diphenylmethane; 2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone; quinone compounds such as 1-chloroanthraquinone and 2-chloroanthraquinone. In addition, photosensitizers such as amines can also be listed as the aforementioned photopolymerization initiators.

The photopolymerization initiator (c) contained in the composition (IV) and the protective film forming film can be one or more types. When there are two or more types, the combination and ratio of these photopolymerization initiators (c) can be arbitrarily selected. For example, highly reactive photopolymerization initiators such as 2-hydroxy-2-methyl-1-phenylpropane-1-one, which are liquid at room temperature, can be used alone to enable efficient crosslinking of the protective film forming film and improve the gel fraction. Low-reactivity photopolymerization initiators such as 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionic)benzyl)phenyl)-2-methylpropane-1-one and 1-hydroxycyclohexyl-phenyl one can be combined with highly reactive photopolymerization initiators such as 2-(dimethylamino)-1-(4-mofolinphenyl)-2-benzyl-1-butanone to enable efficient crosslinking of the protective film and improve the gel fraction.

When using a photopolymerization initiator (c), the content of the photopolymerization initiator (c) in the composition (IV) is 100 parts by mass, preferably 0.1 parts by mass to 20 parts by mass, more preferably 1 part by mass to 10 parts by mass, and even more preferably 2 parts by mass to 5 parts by mass.

(Inorganic Filler Material (d)) When both the composition (IV) and the protective film forming film contain inorganic filler material (d), the coefficient of thermal expansion of the cured component of the protective film forming film (e.g., the protective film) can be more easily adjusted by regulating the amount of inorganic filler material (d) in both the composition (IV) and the protective film forming film. For example, by optimizing the coefficient of thermal expansion of the protective film for the object to which the protective film is formed, the reliability of the encapsulation obtained using the protective film forming film is further improved. Furthermore, by using a protective film forming film containing inorganic filler material (d), the moisture absorption rate of the cured component of the protective film forming film (e.g., the protective film) can also be reduced or heat dissipation improved.

Examples of inorganic filler materials (d) include: powders of inorganic materials such as silicon dioxide, alumina, talc, calcium carbonate, titanium dioxide, iron oxide, silicon carbide, and boron nitride; beads formed by spheroidizing these inorganic fillers; surface-modified products of these inorganic fillers; single-crystal fibers of these inorganic fillers; and glass fibers. Among these, silicon dioxide or alumina is preferred as the inorganic filler material (d).

The inorganic filler material (d) contained in the composition (IV) and the protective film forming film may be only one type or two or more types. In the case of two or more types, the combination and ratio of these inorganic filler materials (d) can be arbitrarily selected.

In composition (IV), the ratio of the content of inorganic filler material (d) to the total content of all components other than the solvent (i.e., the ratio of the content of inorganic filler material (d) in the protective film forming film to the total mass of the protective film forming film) is preferably 35% to 75% by mass, for example, it can also be any one of 45% to 70% by mass and 50% to 65% by mass. By using the aforementioned ratio within this range, the effectiveness brought about by the use of inorganic filler material (d) can be further improved without compromising the characteristics of the protective film forming film.

(Coupling Agent (e)) When both the composition (IV) and the protective film forming film contain a coupling agent (e) having functional groups capable of reacting with inorganic or organic compounds, the adhesion and bonding strength of the protective film forming film relative to the substrate are improved. Furthermore, the hardened form of the protective film forming film (e.g., the protective film itself) can improve water resistance without compromising heat resistance.

The coupling agent (e) is preferably a compound having a functional group capable of reacting with the functional groups of acrylic resin (b), energy line curing component (a), etc., and is more preferably a silane coupling agent. Preferred silane coupling agents include, for example: 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, and 3-(2-aminoethylamino)propyltrimethoxysilane. Alkane, 3-(2-aminoethylamino)propylmethyldiethoxysilane, 3-(phenylamino)propyltrimethoxysilane, 3-anilinepropyltrimethoxysilane, 3-ureopropyltriethoxysilane, 3-caprylylpropyltrimethoxysilane, 3-caprylylpropylmethyldimethoxysilane, bis(3-triethoxysilylpropyl)tetrasulfide, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, imidazolylsilane, etc.

The coupling agent (e) contained in the composition (IV) and the protective film forming film may be only one type or two or more types. In the case of two or more types, the combination and ratio of these coupling agents (e) can be arbitrarily selected.

When using coupling agent (e), the content of coupling agent (e) in composition (IV) and the protective film forming film is preferably 0.03 to 20 parts by mass relative to the total content of energy line curing component (a) and acrylic resin (b) of 100 parts by mass. By having the aforementioned content of coupling agent (e) at or above the aforementioned lower limit, the following effects brought about by the use of coupling agent (e) can be more significantly obtained: improved dispersibility of inorganic filler material (d) in the resin, or improved adhesion between the protective film forming film and the substrate. By having the aforementioned content of coupling agent (e) at or below the aforementioned upper limit, the generation of gas escape can be further suppressed.

(Crosslinking Agent (f)) When the acrylic resin (b) uses components with functional groups such as vinyl, (meth)acrylic, amino, hydroxyl, carboxyl, and isocyanate groups that can bond with other compounds, the composition (IV) and the protective film forming film may also contain a crosslinking agent (f). The crosslinking agent (f) is a component used to crosslink the aforementioned functional groups in the acrylic resin (b) with other compounds. Through this crosslinking, the initial adhesion and cohesion of the protective film forming film can be adjusted.

Examples of crosslinking agents (f) include: organic polyisocyanate compounds, organic polyimine compounds, metal chelate crosslinking agents (crosslinking agents with metal chelate structures), aziridine crosslinking agents (crosslinking agents with aziridine groups), etc.

Examples of the aforementioned organic polyisocyanate compounds include, for example, aromatic polyisocyanate compounds, aliphatic polyisocyanate compounds, and alicyclic polyisocyanate compounds (hereinafter sometimes abbreviated as "aromatic polyisocyanate compounds, etc."); trimers, isocyanurates, and adducts of the aforementioned aromatic polyisocyanate compounds; and terminal isocyanate carbamate prepolymers obtained by reacting the aforementioned aromatic polyisocyanate compounds with polyol compounds. The aforementioned "adduct" refers to the reaction product of the aforementioned aromatic polyisocyanate compounds, aliphatic polyisocyanate compounds, or alicyclic polyisocyanate compounds with compounds containing low-molecular-weight active hydrogen, such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, or castor oil. Examples of the aforementioned adducts include trihydroxymethylpropane dimethyl diisocyanate adducts, as described later. Furthermore, the term "terminated isocyanate carbamate prepolymer" refers to a prepolymer having carbamate bonds and isocyanate groups at the ends of the molecule.

More specifically, examples of the aforementioned organic polyisocyanate compounds include: 2,4-toluene diisocyanate; 2,6-toluene diisocyanate; 1,3-phenylenedimethyl diisocyanate; 1,4-phenylenedimethyl diisocyanate; diphenylmethane-4,4'-diisocyanate; diphenylmethane-2,4'-diisocyanate; 3-methyldiphenylmethane diisocyanate; hexanoate. Methyl diisocyanate; isophorone diisocyanate; dicyclohexylmethane-4,4'-diisocyanate; dicyclohexylmethane-2,4'-diisocyanate; compounds formed by the addition of all or part of the hydroxyl groups of polyols such as trihydroxymethylpropane to toluene diisocyanate, hexamethylene diisocyanate, and phenyl diisocyanate, or two or more thereof; lysine diisocyanate, etc.

Examples of the aforementioned organic polyimide compounds include: N,N’-diphenylmethane-4,4’-bis(1-aziridinium methylamine), trihydroxymethylpropane-tri-β-aziridinium propionate, tetrahydroxymethylmethane-tri-β-aziridinium propionate, and N,N’-toluene-2,4-bis(1-aziridinium methylamine)triethyl melamine.

When an organic polyisocyanate compound is used as the crosslinking agent (f), it is preferable to use a hydroxyl-containing polymer as the acrylic resin (b). When the crosslinking agent (f) has isocyanate groups and the acrylic resin (b) has hydroxyl groups, the crosslinked structure can be easily introduced into the protective film by reacting the crosslinking agent (f) with the acrylic resin (b).

The crosslinking agent (f) contained in the composition (IV) and the protective film forming film may be only one type or two or more types. In the case of two or more types, the combination and ratio of these crosslinking agents (f) can be arbitrarily selected.

When crosslinking agent (f) is used, the content of crosslinking agent (f) in composition (IV) is preferably 0.01 to 20 parts by weight relative to 100 parts by weight of acrylic resin (b). By ensuring that the content of crosslinking agent (f) is above or above the aforementioned lower limit, the efficacy brought about by the use of crosslinking agent (f) can be obtained more significantly. By ensuring that the content of crosslinking agent (f) is below the aforementioned upper limit, the overuse of crosslinking agent (f) is suppressed.

(Colorant (g)) When both the composition (IV) and the protective film contain colorant (g), the light transmittance of the protective film can be adjusted by varying the amount of colorant (g). Furthermore, by adjusting the light transmittance in this way, for example, the laser marking recognition of the protective film or the protective film after laser marking can be adjusted. Additionally, it can improve the design flexibility of the protective film or make grinding marks on the inner surface of the wafer less visible.

As coloring agents (g), examples include: inorganic pigments, organic pigments, organic dyes and other known pigments.

Examples of organic pigments and dyes mentioned above include: amine-based pigments, anthocyanin-based pigments, quinone-based pigments, squalene-based pigments, azuron-based pigments, polymethyl pigments, naphthoquinone-based pigments, pyranone-based pigments, phthalocyanine-based pigments, naphthyl phthalocyanine-based pigments, naphthyl lactone-based pigments, azo-based pigments, condensed azo-based pigments, indigo-based pigments, pyrenone-based pigments, and perylene-based pigments. Dioxazine pigments, quinacridone pigments, isoindolineone pigments, quinolineone pigments, pyrrole pigments, indigo pigments, metal complex pigments (metal chromate dyes), dithiol metal complex pigments, indolephenol pigments, triallylmethane pigments, anthraquinone pigments, naphthol pigments, methylimine pigments, benzimidazole pigments, pinantrone pigments, and vat pigments, etc.

Examples of inorganic pigments mentioned above include: carbon black, cobalt-based pigments, iron-based 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) pigments, and ATO (Antimony Tin Oxide) pigments.

The colorant (g) contained in the composition (IV) and the protective film forming film may be only one type or two or more types. In the case of two or more types, the combination and ratio of these colorants (g) can be arbitrarily selected.

When using a colorant (g), the content of the colorant (g) in the composition (IV) and the protective film forming film can be adjusted appropriately according to the purpose. For example, in cases such as improving the laser marking identification of the protective film or the design of the protective film, or making the grinding marks on the inner surface of the wafer less visible, the ratio of the content of the colorant (g) in the composition (IV) to the total content of all components other than the solvent (i.e., the ratio of the content of the colorant (g) in the protective film forming film to the total mass of the protective film forming film) is preferably 0.05% to 12% by mass, more preferably 0.05% to 9% by mass, and even more preferably 0.1% to 7% by mass. By using the aforementioned ratio at or above the aforementioned lower limit, the effects brought about by the use of the colorant (g) can be more significantly obtained. By keeping the aforementioned ratio below the aforementioned upper limit, the overuse of colorant (g) is suppressed.

(Thermocurable component (h)) When the composition (IV) and the protective film forming film contain both energy-curing component (a) and thermocurable component (h), the protective film forming film enhances its adhesion to the substrate by heating, and also increases the strength of the cured protective film (e.g., the protective film itself).

Examples of thermosetting components (h) include epoxy thermosetting resins, polyimide resins, and unsaturated polyester resins, with epoxy thermosetting resins being preferred.

The aforementioned epoxy thermosetting resin is composed of epoxy resin (h1) and thermosetting agent (h2). The epoxy thermosetting resin contained in component (IV) and the protective film forming film may be only one type or may be two or more types. In the case of two or more types, the combination and ratio of these epoxy thermosetting resins can be arbitrarily selected.

• Epoxy Resins (h1) As for epoxy resins (h1), known epoxy resins can be listed, such as: multifunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ether and its hydrogenates, o-cresol phenolic varnish epoxy resins, dicyclopentadiene-type epoxy resins, biphenyl-type epoxy resins, bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, and phenyl-skeletal epoxy resins, etc., which are epoxy compounds with two or more functions.

As an epoxy resin (h1), epoxy resins with unsaturated hydrocarbon groups can also be used. Epoxy resins with unsaturated hydrocarbon groups have higher compatibility with acrylic resins compared to epoxy resins without unsaturated hydrocarbon groups. Therefore, by using epoxy resins with unsaturated hydrocarbon groups, the reliability of wafers with protective films obtained using protective film forming composites can be improved.

Examples of epoxy resins having unsaturated hydrocarbon groups include compounds formed by converting some epoxy groups in multifunctional epoxy resins into groups having unsaturated hydrocarbon groups. Such compounds can be obtained, for example, by an addition reaction of (meth)acrylic acid or its derivatives with an epoxy group. Furthermore, examples of epoxy resins having unsaturated hydrocarbon groups include compounds in which unsaturated hydrocarbon groups are directly bonded to aromatic rings or other components constituting the epoxy resin. An unsaturated hydrocarbon is a polymerizable unsaturated group. Specific examples of such unsaturated hydrocarbons include: methine (vinyl), 2-propenyl (allyl), (meth)acrylyl, (meth)acrylamino, etc., with acrylyl being preferred.

The number-average molecular weight of the epoxy resin (h1) is not particularly limited, but in terms of the curability, strength, and heat resistance of the protective film, it is preferably 300 to 30,000, more preferably 300 to 10,000, and even more preferably 300 to 3,000. The epoxy equivalent of the epoxy resin (h1) is preferably 100 g/eq to 1,000 g/eq, more preferably 150 g/eq to 950 g/eq.

The epoxy resin (h1) contained in the composition (IV) and the protective film forming film may be only one type or two or more types. In the case of two or more types, the combination and ratio of these epoxy resins (h1) can be arbitrarily selected.

• Thermosetting Agent (h2) Thermosetting agent (h2) functions as a curing agent for epoxy resins (h1). Examples of thermosetting agents (h2) include compounds having two or more functional groups in one molecule that can react with epoxy groups. Examples of such functional groups include phenolic hydroxyl groups, alcoholic hydroxyl groups, amino groups, carboxyl groups, and groups formed by anhydride conversion of acid groups. Phenolic hydroxyl groups, amino groups, or groups formed by anhydride conversion of acid groups are preferred, and phenolic hydroxyl groups or amino groups are even more preferred.

Among thermosetting agents (h2), phenolic curing agents containing phenolic hydroxyl groups include, for example, polyfunctional phenolic resins, biphenol, phenolic varnish-type phenolic resins, dicyclopentadiene-type phenolic resins, and aralkyl-type phenolic resins. Amino curing agents (h2) containing amino groups include, for example, dicyandiamide.

Thermosetting agents (h2) can also contain unsaturated hydrocarbon groups. Examples of thermosetting agents (h2) containing unsaturated hydrocarbon groups include: compounds in which a portion of the hydroxyl groups in a phenolic resin are replaced by unsaturated hydrocarbon groups; and compounds in which unsaturated hydrocarbon groups are directly bonded to the aromatic rings of a phenolic resin. Among the aforementioned unsaturated hydrocarbon groups in thermosetting agents (h2), examples include those identical to the unsaturated hydrocarbon groups in the aforementioned epoxy resins.

When using phenolic curing agents as thermosetting agents (h2), from the perspective of improving the peelability of the protective film's self-supporting sheet, thermosetting agents (h2) with high softening points or glass transition temperatures are preferred.

The average molecular weight of resin components in the thermosetting agent (h2), such as polyfunctional phenolic resins, phenolic varnish-type phenolic resins, dicyclopentadiene-type phenolic resins, and aralkyl-type phenolic resins, is preferably 300 to 30,000, more preferably 400 to 10,000, and even more preferably 500 to 3,000. The molecular weight of non-resin components in the thermosetting agent (h2), such as biphenol and dicyandiamide, is not particularly limited, but is preferably 60 to 500.

The thermosetting agent (h2) contained in the composition (IV) and the protective film forming film may be only one type or two or more types. In the case of two or more types, the combination and ratio of these thermosetting agents (h2) can be arbitrarily selected.

When using a thermosetting component (h), the content of the thermosetting agent (h2) in the composition (IV) and the protective film forming film is preferably 0.1 to 100 parts by mass relative to the content of epoxy resin (h1) per 100 parts by mass. By ensuring that the content of the thermosetting agent (h2) is above the aforementioned lower limit, the curing of the protective film forming film can be facilitated. By ensuring that the content of the thermosetting agent (h2) is below the aforementioned upper limit, the moisture absorption rate of the protective film forming film is reduced, further improving the reliability of the package obtained using the wafer with the protective film.

When using a thermosetting component (h), the content of the thermosetting component (h) in the composition (IV) and the protective film forming film (e.g., the total content of epoxy resin (h1) and thermosetting agent (h2)) relative to the content of acrylic resin (b) is preferably 5 to 120 parts by mass. By using the aforementioned content of the thermosetting component (h) within this range, for example, the adhesion between the hardened material of the protective film forming film and the support sheet is suppressed, thereby improving the peelability of the support sheet.

(General Additive (z)) The general additive (z) can be any known general additive, and can be selected arbitrarily according to the purpose without particular limitation. Preferred general additives (z) include, for example, plasticizers, antistatic agents, antioxidants, getters, and UV absorbers.

The composition (IV) and the protective film forming film contain only one type of general additive (z), or two or more types. When there are two or more types, the combination and ratio of these general additives (z) can be arbitrarily selected.

When using a universal additive (z), there are no particular limitations on the content of the universal additive (z) in both component (IV) and the protective film forming film; it can be selected appropriately according to the purpose. For example, when the universal additive (z) is an ultraviolet absorber, the ratio of the content of the universal additive (z) (ultraviolet absorber) in component (IV) to the total content of all components other than the solvent (i.e., the ratio of the content of the universal additive (z) (ultraviolet absorber) in the protective film forming film to the total mass of the protective film forming film) is preferably 0.1% to 5% by mass. By setting the aforementioned ratio above the lower limit, the effects of using the universal additive (z) can be more significantly obtained. By setting the aforementioned ratio below the upper limit, the excessive use of the universal additive (z) is suppressed.

(Other polymers (b0) without energy-line hardening groups) Other polymers (b0) without energy-line hardening groups impart membrane-forming properties to the protective film. The aforementioned polymers (b0) are not particularly limited as long as they are not equivalent to acrylic resin (b). The aforementioned polymers (b0) may be at least partially crosslinked using a crosslinking agent, or they may not be crosslinked.

Examples of the aforementioned polymers (b0) include: acrylic resins with a weight average molecular weight exceeding 1,100,000; acrylic resins with a dispersion of 3.0 or less (in this specification, these acrylic resins are sometimes referred to as "other acrylic resins"); and polymers other than acrylic resins that do not have energy line hardening groups.

Other acrylic resins mentioned above, except for those with a weight average molecular weight exceeding 1,100,000 or a dispersion of 3.0 or less, are similar to acrylic resin (b).

Polymers other than acrylic resins that do not have energy-curing groups include, for example, urethane resins, phenoxy resins, polysiloxane resins, saturated polyester resins, etc.

The weight average molecular weight (Mw) of polymers other than acrylic resins that do not have energy line hardening groups is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1,500,000, in terms of improving the film-forming properties of the composition (IV).

The aforementioned polymer (b0) contained in the composition (IV) and the protective film forming film may be only one type or two or more types. In the case of two or more types, the combination and ratio of these polymers (b0) can be arbitrarily selected.

In the composition (IV) and the protective film forming membrane, the content of polymer (b0) relative to the content of acrylic resin (b) is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, even more preferably 1 part by mass or less, and most preferably 0 parts by mass (i.e., preferably the composition (IV) and the protective film forming membrane do not contain polymer (b0)). By ensuring that the aforementioned content of polymer (b0) is below the aforementioned upper limit, the aforementioned seepage caused by the reflux step is suppressed.

[Soluble Medium] Composition (IV) preferably contains a solvent. The operability of composition (IV) containing a solvent improves. The aforementioned solvent is not particularly limited. Preferred solvents include, for example: hydrocarbons such as toluene and xylene; alcohols such as methanol, ethanol, 2-propanol, isobutanol (2-methylpropane-1-ol), and 1-butanol; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; and amides (compounds containing amide bonds) such as dimethylformamide and N-methylpyrrolidone. Composition (IV) may contain only one solvent or two or more solvents. In the case of two or more solvents, the combination and ratio of these solvents can be arbitrarily selected.

The solvent contained in composition (IV), for example, is a better solvent in terms of making the components contained in composition (IV) mix more evenly, such as methyl ethyl ketone.

There is no particular limitation on the content of solvent in component (IV). For example, it can be appropriately selected according to the type of components other than solvent.

[Manufacturing Method of Composition for Protective Film Formation] Composition (IV) isoelectric line curing protective film formation composition can be obtained by formulating the components used to constitute the composition. The order in which the components are added during formulation is not particularly limited, and two or more components may be added simultaneously. The method of mixing the components during formulation is not particularly limited; any of the following known methods may be appropriately selected: mixing by rotating a stir bar or stirring blade; mixing using a mixer; mixing by applying ultrasound, etc. Regarding the temperature and time for adding and mixing the components, there are no particular limitations as long as the formulation components are not degraded; they may be adjusted appropriately. A temperature of 15°C to 30°C is preferred.

Figure 1 is a cross-sectional view schematically illustrating an example of a protective film forming film of the present embodiment. Furthermore, in order to facilitate understanding of the features of the present invention, some parts that are important are sometimes enlarged for convenience, and the size ratios of each component may not be the same as the actual dimensions.

The protective film 13 shown here has a first peeling film 151 on one side (sometimes referred to as the "first side" in this specification) 13a, and a second peeling film 152 on the opposite side (sometimes referred to as the "second side" in this specification) 13b. This protective film 13 is suitable, for example, for storage in a roller shape.

The protective film forming film 13 possesses the aforementioned characteristics. The protective film forming film 13 can be formed using the aforementioned protective film forming composition.

Both the first exfoliating membrane 151 and the second exfoliating membrane 152 are known. The first exfoliating membrane 151 and the second exfoliating membrane 152 may be the same as each other, or they may be different from each other, for example, by having different exfoliating forces required for the formation of the protective membrane 13.

The protective film forming film 13 shown in Figure 1 exposes the inner surface of the wafer (not shown) after removing either the first release film 151 or the second release film 152. Furthermore, the exposed surface of the remaining release film of the first release film 151 and the second release film 152 becomes the attachment surface of the support sheet or dicing sheet described later.

Figure 1 shows an example where the peeling membrane is disposed on both sides (first side 13a, second side 13b) of the protective film forming membrane 13, but the peeling membrane may also be disposed on only one side of the protective film forming membrane 13 (i.e. only the first side 13a, or only the second side 13b).

The protective film forming membrane of this embodiment has the following aspects. "1" A protective film forming membrane is an energy-line hardening protective film forming membrane; the aforementioned protective film forming membrane contains an energy-line hardening component (a); the weight reduction rate ( _ΔW3 ) of the protective film after energy-line hardening and heat treatment at 260°C for 10 minutes relative to the weight ( _W0 ) of the aforementioned protective film forming membrane before energy-line hardening is 3.0% _or less, preferably 2.8% or less, more preferably 2.6% or less, and even more preferably 2.4% or less; after energy-line hardening of the aforementioned protective film forming membrane, the gel content of components other than inorganic filler materials is 60% or more. "2" As described in "1" above, the gloss value (G2) of the protective film formed after energy line curing and heat treatment at 260°C for 10 minutes is reduced by 30% or less, preferably 28% or less, and more preferably 26% or less. "3" As described in "1" or "2" above, the energy line curing component (a) contains a polyfunctional (meth)acrylate oligomer. "4" As described in any of "1" to "3" above, the weight reduction rate _ΔW1 of the protective film formed after the protective film formed by heating it at 130°C for 2 hours relative to the weight ( _W0 ) of the protective film formed before heat treatment is _1.5 % or less, more preferably 1.4% or less, and even more preferably 1.3% or less. "5" As described in any of "1" to "4" above, the weight reduction rate _ΔW2 of the protective film formed after energy line hardening of the protective film formed by the protective film formed by the protective film formed after energy _line hardening is _0.30 % or less, more preferably 0.25% or less, and even more preferably 0.20% or less.

"6" The protective film forming film as described in any one of "1" to "5" above, wherein the protective film forming film contains the aforementioned energy line curing component (a), an acrylic resin (b) without energy line curing groups, and an inorganic filler material (d). "7" The protective film forming film as described in "6" above, wherein in the aforementioned acrylic resin (b), the ratio (content) of the constituent units derived from functionalized monomers to the total amount of constituent units constituting the aforementioned acrylic resin (b) is 1% to 20% by mass, more preferably 2% to 10% by mass. "8" The protective film forming film as described in "6" or "7" above, wherein the content of acrylic resin (b) relative to the total mass of the protective film forming film is 8% by mass or more, more preferably 10% by mass or more, even more preferably 12% by mass or more, and particularly preferably 14% by mass or more. "9" The protective film forming film as described in any one of "6" to "8" above, wherein the content of acrylic resin (b) relative to the total mass of the protective film forming film is 27% by mass or less, more preferably 25% by mass or less, even more preferably 23% by mass or less, and even more preferably 21% by mass or less. "10" The protective film forming film as described in any of "6" to "9" above, wherein the content of the energy line hardening component (a) relative to the total mass of the protective film forming film is 12% to 31% by mass, more preferably 14% to 28% by mass, and even more preferably 16% to 25% by mass, and the total content of the components contained in the protective film forming film does not exceed 100% by mass. "11" The protective film forming film as described in any of "1" to "10" above, wherein the protective film forming film contains a photopolymerization initiator (c). "12" The protective film forming film as described in "11" above, wherein the aforementioned photopolymerization initiator (c) contains 2-hydroxy-2-methyl-1-phenylpropane-1-one; or contains 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropoxy)benzyl)phenyl)-2-methylpropane-1-one; or contains 1-hydroxycyclohexyl-phenyl one and 2-(dimethylamino)-1-(4-mofolinphenyl)-2-benzyl-1-butanone.

The protective film forming film of this embodiment can be attached to the inner surface of the wafer without being used in conjunction with the support sheet described later. In this case, a release film can also be provided on the side opposite to the wafer attachment surface of the protective film forming film, which can be removed at an appropriate time.

On the other hand, the protective film forming film of this embodiment can be used in conjunction with the support sheet described later to simultaneously form and cut the protective film, thereby constituting a composite sheet for forming a protective film. This composite sheet for forming a protective film will be described below.

◇Composite Sheet for Protective Film Formation One embodiment of the present invention provides a composite sheet for protective film formation comprising: a support sheet and a protective film forming film disposed on one side of the support sheet; the aforementioned protective film forming film is the protective film forming film of one embodiment of the present invention. The composite sheet for protective film formation of this embodiment, by having the aforementioned protective film forming film, suppresses the seepage caused by the reflow step during the formation of the protective film.

In this manual, even after the protective film has hardened, as long as the laminated structure of the support sheet and the hardened protective film is maintained, the laminated structure is still referred to as a "composite sheet for forming a protective film".

The following is a detailed description of each layer of the composite sheet constituting the aforementioned protective film formation.

◎Supporting Sheet The aforementioned supporting sheet may consist of a single layer or multiple layers (two or more). When the supporting sheet is composed of multiple layers, the materials and thicknesses of these layers may be the same or different. The combination of these layers is not particularly limited as long as it does not impair the function of the invention.

The support sheet is preferably transparent, but can also be colored depending on the purpose. In this embodiment where the protective film forming film has energy line hardening properties, the support sheet is preferably designed to allow energy lines to pass through.

Examples of support sheets include: a support sheet having a substrate and an adhesive layer disposed on one side of the substrate; and a support sheet consisting only of a substrate. When the support sheet has an adhesive layer, the adhesive layer is disposed between the substrate and the protective film forming film in the composite sheet for forming the protective film.

When using a support sheet comprising a substrate and an adhesive layer, the adhesion and peelability between the support sheet and the protective film forming film in the protective film forming composite sheet can be easily adjusted. When using a support sheet consisting solely of a substrate, the protective film forming composite sheet can be manufactured at a low cost.

The following describes examples of composite sheets for forming protective films in this embodiment, with reference to the drawings, for each type of such support sheet.

Figure 2 is a cross-sectional view schematically showing an example of a protective film forming composite sheet of the present embodiment. Furthermore, in the figures below Figure 2, the same constituent elements shown in the previously described figures are labeled with the same symbols as in the previously described figures, and detailed descriptions of the constituent elements are omitted.

The protective film forming composite sheet 101 shown here comprises: a support sheet 10 and a protective film forming film 13 disposed on one side (sometimes referred to as "first side") 10a of the support sheet 10. The support sheet 10 comprises: a substrate 11 and an adhesive layer 12 disposed on one side (first side) 11a of the substrate 11. In the protective film forming composite sheet 101, the adhesive layer 12 is disposed between the substrate 11 and the protective film forming film 13. That is, the protective film forming composite sheet 101 is formed by sequentially laminating the substrate 11, the adhesive layer 12, and the protective film forming film 13 in the thickness direction of these layers. The first surface 10a of the support sheet 10 is the same as the surface opposite to the substrate 11 side of the adhesive layer 12 (sometimes referred to as "first surface" in this specification) 12a.

The protective film forming composite sheet 101 further comprises a jig adhesive layer 16 and a peeling film 15 on the protective film forming film 13. In the protective film forming composite sheet 101, the protective film forming film 13 is laminated on the entire or almost entire surface of the first surface 12a of the adhesive layer 12, and a jig adhesive layer 16 is laminated on a portion of the surface (sometimes referred to as the "first surface" in this specification) 13a opposite to the adhesive layer 12 of the protective film forming film 13, i.e., in the area near the periphery. Furthermore, a release film 15 is deposited on the first surface 13a of the protective film forming film 13, in the area where the fixture adhesive layer 16 is not deposited, and on the opposite side of the protective film forming film 13 of the fixture adhesive layer 16 (sometimes referred to as the "first surface" in this specification) 16a. A support sheet 10 is provided on the opposite side of the first surface 13a of the protective film forming film 13 (sometimes referred to as the "second surface" in this specification) 13b.

Not limited to the protective film forming composite sheet 101, in the protective film forming composite sheet of this embodiment, the peeling membrane (for example, the peeling membrane 15 shown in FIG1) can be of any configuration. The protective film forming composite sheet of this embodiment may or may not have a peeling membrane.

The adhesive layer 16 for the fixture is used to fix the protective film forming composite sheet 101 to a fixture such as an annular frame. The adhesive layer 16 for the fixture may have, for example, a single-layer structure containing adhesive components, or a multi-layer structure, wherein the multi-layer structure comprises a sheet serving as a core material, and layers containing adhesive components disposed on both sides of the aforementioned sheet.

With the protective film forming composite sheet 101 in the state of having the peeling film 15 removed, the inner surface of the wafer is attached to the first surface 13a of the protective film forming film 13, and then the first surface 16a of the fixture bonding agent layer 16 is attached to a fixture such as a ring frame for use.

Figure 3 is a cross-sectional view schematically showing another example of the protective film forming composite sheet of this embodiment. The protective film forming composite sheet 102 shown here is the same as the protective film forming composite sheet 101 shown in Figure 2, except that the shape and size of the protective film forming film are different, and the adhesive layer for the fixture is deposited on the first surface of the adhesive layer instead of on the first surface of the protective film forming film.

More specifically, in the protective film forming composite sheet 102, the protective film forming film 23 is deposited on a portion of the first surface 12a of the adhesive layer 12 (that is, the central area of the adhesive layer 12 in the width direction (left-right direction in FIG. 3)). Furthermore, in the area of the first surface 12a of the adhesive layer 12 where the protective film forming film 23 is not deposited, the adhesive layer 16 for jig is deposited from the outer side of the protective film forming film 23 in a non-contact manner. Furthermore, a release film 15 is laminated between the first surface 16a of the adhesive layer 12 of the protective film forming film 23 (sometimes referred to as the "first surface" in this specification) and the first surface 16a of the fixture adhesive layer 16. A support sheet 10 is provided on the second surface 23b of the protective film forming film 23 (sometimes referred to as the "second surface" in this specification).

Figure 4 is a cross-sectional view schematically illustrating another example of the protective film forming composite sheet of this embodiment. The protective film forming composite sheet 103 shown here is identical to the protective film forming composite sheet 102 shown in Figure 3, except that it lacks the adhesive layer 16 for the jig.

Figure 5 is a cross-sectional view schematically illustrating another example of the protective film forming composite sheet of this embodiment. The protective film forming composite sheet 104 shown here is identical to the protective film forming composite sheet 101 shown in Figure 2, except that it replaces the support sheet 10 with a support sheet 20.

The support sheet 20 is composed solely of the substrate 11. That is, the protective film forming composite sheet 104 is formed by laminating the substrate 11 and the protective film forming film 13 in the thickness direction of these layers. The side surface (first side) 20a of the protective film forming film 13 of the support sheet 20 is identical to the first side surface 11a of the substrate 11. The substrate 11 has adhesiveness at least within the first side surface 11a.

The protective film forming composite sheet of this embodiment is not limited to that shown in Figures 2 to 5. Without impairing the effectiveness of the invention, some components may be modified or deleted from those shown in Figures 2 to 5, and other components may be added to those described so far.

Next, a detailed explanation of each layer that makes up the support sheet is provided.

○ Substrate The aforementioned substrate is in sheet or film form. Examples of materials constituting the aforementioned substrate include various resins. Examples of such resins include: polyethylene such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and high-density polyethylene (HDPE); polyolefins other than polyethylene such as polypropylene, polybutene, polybutadiene, polymethylpentene, and norbornene resins; and ethylene-based copolymers such as ethylene-vinyl acetate copolymer, ethylene-(meth)acrylate copolymer, ethylene-(meth)acrylate copolymer, and ethylene-norbornene copolymer. Copolymers (copolymers obtained using ethylene as a monomer); vinyl chloride resins (resins obtained using vinyl chloride as a monomer), such as polyvinyl chloride and vinyl chloride copolymers; polystyrene; polycyclic aromatic hydrocarbons; polyethylene terephthalate, polyethylene naphthalate, polyethylene terephthalate, polyethylene isophthalate, polyethylene 2,6-naphthalenedicarboxylate, and other fully aromatic polyesters whose constituent units all have aromatic cyclic groups; copolymers of two or more of the aforementioned polyesters; poly(meth)acrylates; polyurethane; polyurethane acrylates; polyimide; polyamide; polycarbonate; fluororesins; polyacetal; modified polyphenylene ether; polyphenylene sulfide; polyurethane; polyetherketone, etc. Furthermore, as the aforementioned resin, examples include polymer alloys such as mixtures of the aforementioned polyester and resins other than the aforementioned polyester. Preferably, in polymer alloys of the aforementioned polyester and resins other than the aforementioned polyester, the amount of resins other than the polyester is relatively small. Furthermore, as the aforementioned resin, examples include: crosslinked resins formed by crosslinking one or more of the aforementioned resins; modified resins using one or more of the aforementioned ionic polymers.

The resin constituting the base material may be of only one type or of two or more types. In the case of two or more types, the combination and ratio of these resins can be arbitrarily selected.

The substrate can be composed of one layer (single layer) or multiple layers (two or more layers). When the substrate is composed of multiple layers, these multiple layers can be the same or different from each other, and there is no particular limitation on the combination of these multiple layers.

The substrate thickness is preferably between 50 μm and 300 μm, more preferably between 60 μm and 100 μm. This thickness range improves the flexibility of the composite sheet used for forming the protective film and its adhesion to the wafer. Here, "substrate thickness" refers to the overall thickness of the substrate. For example, the thickness of a multi-layered substrate refers to the total thickness of all layers constituting the substrate.

In addition to the aforementioned main constituent materials such as resins, the substrate may also contain various known additives such as fillers, colorants, antioxidants, organic lubricants, catalysts, and plasticizers.

The substrate is preferably transparent, but it can also be colored depending on the purpose, and other layers can be vapor-deposited. In this embodiment where the protective film forms a film with energy line hardening properties, the substrate is preferably designed to allow energy lines to pass through.

To adjust the adhesion of the substrate to layers disposed on it (such as adhesive layers, protective film forming films, or other aforementioned layers), the following treatments may be applied to the surface: roughening treatments such as sandblasting and solvent treatment; oxidation treatments such as corona discharge treatment, electron beam irradiation treatment, plasma treatment, ozone-ultraviolet irradiation treatment, flame treatment, chromic acid treatment, and hot air treatment; oleophilic treatment; and hydrophilic treatment. Additionally, a primer treatment may be applied to the surface of the substrate.

The substrate may also have adhesiveness on at least one side by containing a specific range of components (such as resin).

The substrate can be manufactured using known methods. For example, a resin-containing substrate can be manufactured by molding a resin composition containing the aforementioned resin.

○ Adhesive Layer The aforementioned adhesive layer is in sheet or film form and contains an adhesive. Examples of the aforementioned adhesive include: acrylic resins, carbamate resins, rubber-based resins, polysiloxane resins, epoxy resins, polyvinyl ether, polycarbonate, ester-based resins, and other adhesive resins.

In this manual, "adhesive resin" includes both adhesive resin and bonding resin. For example, the aforementioned adhesive resin includes not only resins that are adhesive in themselves, but also resins that exhibit adhesiveness when used in combination with other ingredients such as additives, or resins that exhibit bondingness when triggered by heat or water.

The adhesive layer can consist of a single layer or multiple layers, either two or more. When the adhesive layer consists of multiple layers, these layers can be the same or different from each other, and there are no particular restrictions on the combination of these layers.

The thickness of the adhesive layer is not particularly limited, but is preferably 1 μm to 100 μm, more preferably 1 μm to 60 μm, and even more preferably 1 μm to 30 μm. Here, "thickness of the adhesive layer" refers to the overall thickness of the adhesive layer, such as the thickness of an adhesive layer composed of multiple layers, meaning the total thickness of all the layers constituting the adhesive layer.

The adhesive layer is preferably transparent, but can also be colored depending on the purpose. In this embodiment where the protective film forms a film with energy line hardening properties, the adhesive layer preferably allows energy lines to pass through.

The adhesive layer can be either line-hardened or non-line-hardened. The properties of the line-hardened adhesive layer can be adjusted before and after hardening. For example, by hardening the line-hardened adhesive layer before picking up the chip with the protective film, the chip with the protective film can be picked up more easily.

An adhesive layer can be formed using an adhesive composition containing an adhesive. For example, by applying an adhesive composition to the object surface to which the adhesive layer is to be formed and drying it as needed, an adhesive layer can be formed on the target area. The ratio of the non-vaporizing components in the adhesive composition to each other at room temperature is usually the same as the ratio of the aforementioned components in the adhesive layer.

In the adhesive layer, the total content of one or more of the ingredients described below (described later) in the adhesive layer does not exceed 100% by mass relative to the total mass of the adhesive layer. Similarly, in the adhesive composition, the total content of one or more of the ingredients described below (described later) in the adhesive composition does not exceed 100% by mass relative to the total mass of the adhesive composition.

The application and drying of the adhesive composition can be carried out, for example, by the same method as the application and drying of the composition for forming the protective film described above.

When an adhesive layer is applied to a substrate, it can be done by simply applying an adhesive composition to the substrate and drying it as needed. Alternatively, an adhesive layer can be pre-formed on the release liner by applying an adhesive composition to the release liner and drying it as needed, and then depositing the adhesive layer on the substrate by attaching the exposed side of the adhesive layer to a surface of the substrate. In this case, the release liner can be removed at any time during the manufacturing process of the protective film forming composite sheet or during use.

When the adhesive layer is energy-line hardening, the following are examples of energy-line hardening adhesive compositions: an adhesive composition containing a non-energy-line hardening adhesive resin (I-1a) (hereinafter sometimes abbreviated as "adhesive resin (I-1a)") and an energy-line hardening compound (I-1); an adhesive composition containing an energy-line hardening adhesive resin (I-2a) (hereinafter sometimes abbreviated as "adhesive resin (I-2a)") with unsaturated groups introduced into the side chains of the non-energy-line hardening adhesive resin (I-1a) (I-2); and an adhesive composition containing the aforementioned adhesive resin (I-2a) and an energy-line hardening compound (I-3), etc.

When the adhesive layer is non-energy-line hardening, examples of non-energy-line hardening adhesive compositions include adhesive compositions (I-4) containing the aforementioned non-energy-line hardening adhesive resin (I-1a).

[Non-energy-line curing adhesive resin (I-1a)] The aforementioned adhesive resin (I-1a) is preferably an acrylic resin.

Examples of the aforementioned acrylic resins include, for example, acrylic polymers having at least one constituent unit derived from an alkyl (meth)acrylate. Examples of the aforementioned alkyl (meth)acrylates include, for example, alkyl groups having 1 to 20 carbon atoms, preferably linear or branched.

In addition to the constituent units derived from (meth)acrylate alkyl esters, the aforementioned acrylic polymer preferably further comprises constituent units derived from functionalized monomers. Examples of such functionalized monomers include: monomers that introduce unsaturated groups into the side chains of the acrylic polymer by reacting the aforementioned functional groups with crosslinking agents described later, or by reacting the aforementioned functional groups with isocyanate groups, glycidyl groups, or other functional groups in compounds containing unsaturated groups described later.

Examples of functionalized monomers include, for example, monomers containing hydroxyl groups, monomers containing carboxyl groups, monomers containing amino groups, and monomers containing epoxy groups.

The aforementioned acrylic polymers, in addition to having constituent units derived from alkyl (meth)acrylates and those derived from functionalized monomers, may also have constituent units derived from other monomers. These other monomers are not particularly limited as long as they can copolymerize with alkyl (meth)acrylates, etc. Examples of these other monomers include: styrene, α-methylstyrene, ethylene-toluene, vinyl formate, vinyl acetate, acrylonitrile, acrylamide, etc.

In the aforementioned adhesive composition (I-1), adhesive composition (I-2), adhesive composition (I-3) and adhesive composition (I-4) (hereinafter including these adhesive compositions, abbreviated as "adhesive composition (I-1) to adhesive composition (I-4)"), the aforementioned acrylic polymer and other acrylic resins may have only one type of constituent unit or two or more types. In the case of two or more types, the combination and ratio of these constituent units can be arbitrarily selected.

In the aforementioned acrylic polymer, the ratio of the amount of the constituent unit derived from the functional group to the total amount of the constituent unit is preferably 1% to 35% by mass.

The adhesive composition (I-1) or adhesive composition (I-4) may contain only one type of adhesive resin (I-1a) or two or more types. In the case of two or more types, the combination and ratio of these adhesive resins (I-1a) can be arbitrarily selected.

In the adhesive layer formed by adhesive composition (I-1) or adhesive composition (I-4), the content of adhesive resin (I-1a) relative to the total mass of the aforementioned adhesive layer is preferably 5% to 99% by mass, for example, it can also be any one of 25% to 95% by mass, 45% to 95% by mass, and 65% to 95% by mass.

[Energy Line Curing Adhesive Resin (I-2a)] The aforementioned adhesive resin (I-2a) can be obtained, for example, by reacting the functional groups of the adhesive resin (I-1a) with a compound containing unsaturated groups that have energy line polymerizability unsaturated groups.

The aforementioned compounds containing unsaturated groups are compounds that, in addition to possessing the aforementioned energy-line polymerizable unsaturated groups, further possess a group capable of bonding with the adhesive resin (I-1a) through reaction with functional groups in the adhesive resin (I-1a). Examples of the aforementioned energy-line polymerizable unsaturated groups include: (meth)acrylonitrile, vinyl(ethylene), allyl(2-propenyl), etc., with (meth)acrylonitrile being preferred. Examples of groups capable of bonding with functional groups in the adhesive resin (I-1a) include: isocyanate groups and glycidyl groups that can bond with hydroxyl or amino groups, and hydroxyl and amino groups that can bond with carboxyl or epoxy groups.

Examples of compounds containing unsaturated groups include: methacryloxyethyl isocyanate, methacrylamide isocyanate, and glycidyl methacrylate.

The adhesive composition (I-2) or adhesive composition (I-3) may contain only one type of adhesive resin (I-2a) or two or more types. In the case of two or more types, the combination and ratio of these adhesive resins (I-2a) can be arbitrarily selected.

In the adhesive layer formed by the self-adhesive composition (I-2) or the adhesive composition (I-3), the content of adhesive resin (I-2a) relative to the total mass of the aforementioned adhesive layer is preferably 5% to 99% by mass.

[Energy Line Hardening Compounds] The energy line hardening compounds contained in the aforementioned adhesive composition (I-1) or adhesive composition (I-3) can include monomers or oligomers having energy line polymerizable unsaturated groups and capable of being hardened by irradiation with energy lines.

Among energy line-curing compounds, examples of monomers include: trimethylolpropane tri(meth)acrylate, pentaerythritol (meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol (meth)acrylate, and other poly(meth)acrylates; methacrylate aminocarbamates; polyester (meth)acrylates; polyether (meth)acrylates; epoxy (meth)acrylates, etc. Among energy line-curing compounds, examples of oligomers include oligomers of polymers containing the monomers exemplified above.

The adhesive composition (I-1) or adhesive composition (I-3) may contain only one or more of the aforementioned energy line hardening compounds. In the case of two or more, the combination and ratio of these energy line hardening compounds may be arbitrarily selected.

In the adhesive layer formed by the self-adhesive composition (I-1) or the adhesive composition (I-3), the ratio of the content of the aforementioned energy line hardening compound to the total mass of the aforementioned adhesive layer is preferably 1% to 95% by mass.

[Crosslinking Agent] As an adhesive resin (I-1a), when using the aforementioned acrylic polymer that has constituent units derived from functional groups in addition to those derived from alkyl (meth)acrylates, adhesive composition (I-1) or adhesive composition (I-4) preferably contains a crosslinking agent. Furthermore, as an adhesive resin (I-2a), when using, for example, the aforementioned acrylic polymer with constituent units derived from functional groups, similar to those in adhesive resin (I-1a), adhesive composition (I-2) or adhesive composition (I-3) may also contain a crosslinking agent.

The aforementioned crosslinking agent, for example, reacts with the aforementioned functional groups to crosslink the adhesive resins (I-1a) with each other or the adhesive resins (I-2a) with each other. Examples of crosslinking agents include: isocyanate-based crosslinking agents such as toluene diisocyanate, hexamethylene diisocyanate, phenyl diisocyanate, and adducts of these diisocyanates (crosslinking agents with isocyanate groups); epoxy-based crosslinking agents such as ethylene glycol glycidyl ether (crosslinking agents with glycidyl groups); aziridine-based crosslinking agents such as hexa[1-(2-methyl)-aziridine]triphosphine triazine (crosslinking agents with aziridine groups); metal chelate-based crosslinking agents such as aluminum chelates (crosslinking agents with metal chelate structures); and isocyanurate-based crosslinking agents (crosslinking agents with an isocyanuric acid skeleton), etc.

The adhesive composition (I-1) to adhesive composition (I-4) may contain only one type of crosslinking agent or two or more types. In the case of two or more types, the combination and ratio of these crosslinking agents can be arbitrarily selected.

In the aforementioned adhesive composition (I-1) or adhesive composition (I-4), the content of the crosslinking agent relative to 100 parts by weight of the adhesive resin (I-1a) is preferably 0.01 to 50 parts by weight, for example, it can also be any one of 1 to 40 parts by weight, 5 to 35 parts by weight, and 10 to 30 parts by weight. In the aforementioned adhesive composition (I-2) or adhesive composition (I-3), the content of the crosslinking agent relative to 100 parts by weight of the adhesive resin (I-2a) is preferably 0.01 to 50 parts by weight.

[Photopolymerization Initiator] Adhesive components (I-1), (I-2), and (I-3) (hereinafter referred to as "Adhesive Components (I-1) to Adhesive Components (I-3)") may further contain a photopolymerization initiator. Adhesive components (I-1) to (I-3) containing a photopolymerization initiator can undergo sufficient curing reaction even when irradiated with relatively low-energy rays such as ultraviolet light.

As a photopolymerization initiator, examples of those identical to the aforementioned photopolymerization initiator (c) can be listed.

The photopolymerization initiator contained in the adhesive composition (I-1) to the adhesive composition (I-3) may be only one type or two or more types. In the case of two or more types, the combination and ratio of these photopolymerization initiators can be arbitrarily selected.

In adhesive composition (I-1), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by weight per 100 parts by weight of the aforementioned energy line curing compound. In adhesive composition (I-2), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by weight per 100 parts by weight of the adhesive resin (I-2a). In adhesive composition (I-3), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by weight per 100 parts by weight of the total content of the adhesive resin (I-2a) and the aforementioned energy line curing compound.

[Other Additives] Adhesive compositions (I-1) to (I-4) may also contain other additives, not equivalent to any of the above-mentioned components, to the extent that they do not impair the effectiveness of the invention. Examples of such other additives include, for example, antistatic agents, antioxidants, softeners (plasticizers), fillers, rust inhibitors, colorants (pigments, dyes), sensitizers, adhesive enhancers, reaction retarders, crosslinking accelerators (catalysts), and other known additives. Furthermore, a reaction retarder, for example, is a component used to inhibit the action of a catalyst mixed in adhesive components (I-1) to (I-4), thereby preventing unintended cross-linking reactions from occurring in the stored adhesive components (I-1) to (I-4). Examples of reaction retarders include those that form chelate complexes by targeting the catalyst; more specifically, those having two or more carbonyl groups (-C(=O)-) in one molecule.

The adhesive composition (I-1) to adhesive composition (I-4) may contain only one or more other additives. In the case of two or more additives, the combination and ratio of these other additives may be arbitrarily selected.

There are no particular limitations on the content of other additives in adhesive compositions (I-1) to adhesive compositions (I-4), and they can be selected appropriately according to the type of additive.

[Soluble Material] Adhesive components (I-1) to (I-4) may also contain a solvent. By including a solvent in adhesive components (I-1) to (I-4), the application suitability to the target surface can be improved.

The aforementioned solvent is preferably an organic solvent. Examples of such organic solvents include: ketones such as methyl ethyl ketone and acetone; esters (carboxylic acid esters) such as ethyl acetate; ethers such as tetrahydrofuran and dioxane; aliphatic hydrocarbons such as cyclohexane and n-hexane; aromatic hydrocarbons such as toluene and xylene; and alcohols such as 1-propanol and 2-propanol.

The adhesive composition (I-1) to adhesive composition (I-4) may contain only one type of solvent or two or more types of solvents. In the case of two or more types of solvents, the combination and ratio of these solvents may be arbitrarily selected.

There is no particular limitation on the content of solvent in adhesive composition (I-1) to adhesive composition (I-4), as long as it is adjusted appropriately.

Method for Manufacturing Adhesive Compositions Adhesive compositions (I-1) to (I-4), etc., can be obtained by formulating the aforementioned adhesive and, as needed, adding other components besides the aforementioned adhesive to form the various components constituting the adhesive composition. The adhesive compositions, except for differences in the types of formulated components, can be manufactured using the same method as the protective film forming compositions described above.

◇Manufacturing Method of Composite Sheet for Protective Film Formation The aforementioned composite sheet for protective film formation can be manufactured by laminating layers in a manner corresponding to the positional relationships of the aforementioned layers, and by adjusting the shape of some or all of the layers as needed. The formation method of each layer is as described above.

For example, when manufacturing support sheets, if an adhesive layer is deposited on a substrate, simply apply the aforementioned adhesive composition to the substrate and dry it as needed. Alternatively, even if the adhesive layer is pre-formed on the release liner by applying the adhesive composition to the release liner and drying it as needed, and then attaching the exposed surface of the adhesive layer to a surface of the substrate, the adhesive layer can still be deposited on the substrate. In this case, it is preferable to apply the adhesive composition to the release treatment surface of the release liner. So far, examples have been given of adhesive layers deposited on a substrate. However, the method described above can also be applied to cases where layers other than adhesive layers are deposited on the substrate.

On the other hand, when a protective film is to be deposited on an adhesive layer already deposited on a substrate, a protective film forming component can be applied to the adhesive layer to directly form the protective film forming film. Layers other than the protective film forming film can also be formed using the same component and deposited on the adhesive layer in the same manner. Thus, when a new layer (hereinafter referred to as "the second layer") is formed on any layer already deposited on the substrate (hereinafter referred to as "the first layer") to form a continuous two-layer laminated structure (in other words, a laminated structure of the first and second layers), the following method can be applied: The composition used to form the second layer is applied to the aforementioned first layer, and dried as necessary. Preferably, the second layer is pre-formed on the release membrane using a composition for forming the second layer. The exposed surface of this pre-formed second layer, opposite to the side contacting the release membrane, is then adhered to the exposed surface of the first layer, forming a continuous two-layer laminated structure. Preferably, the aforementioned composition is applied to the release treatment surface of the release membrane. The release membrane can be removed as needed after the laminated structure is formed. Here, although the example given is of a protective film formed by laminating a protective film on an adhesive layer, any laminated structure can be chosen, such as when a layer (film) other than the protective film is formed on the adhesive layer.

Thus, since all layers other than the substrate constituting the composite sheet for forming the protective film can be deposited by pre-forming them on the release film and then bonding them to the surface of the target layer, the composite sheet for forming the protective film can be manufactured by simply selecting the appropriate layers to use as needed.

In addition, the protective film forming composite sheet is usually preserved with a release film attached to the outermost surface (e.g., the protective film forming film) on the opposite side of the support sheet. Therefore, a protective film forming component or other component used to form the outermost layer is applied to the release membrane (preferably the release treatment surface of the release membrane), and dried as needed. The outermost layer is pre-formed on the release membrane. On the exposed surface of the layer opposite to the side in contact with the release membrane, the remaining layers are deposited using any of the methods described above. The release membrane is not removed, and the membrane remains adhered, thereby obtaining a protective film forming composite sheet with a release membrane.

◇Method for Manufacturing a Wafer with a Protective Film (Method for Using a Protective Film Forming Film and a Composite for Protective Film Formation) The aforementioned protective film forming film and composite for protective film formation can be used to manufacture the aforementioned wafer with a protective film. That is, one embodiment of the present invention's method for manufacturing a wafer with a protective film is used to manufacture a wafer having a protective film and a protective film disposed on the inner surface of the wafer; it includes the following steps: by attaching the aforementioned protective film forming film of one embodiment of the present invention to the inner surface of the wafer, a first laminated film is formed by stacking the aforementioned protective film forming film and the wafer in the thickness direction of these layers; or by attaching the aforementioned protective film forming film of one embodiment of the present invention to the inner surface of the wafer. The step of forming a first laminated composite film by sequentially stacking the aforementioned support sheet, protective film forming film, and wafer in the thickness direction of these layers using the aforementioned protective film forming film in the composite film (sometimes referred to as the "attachment step" in this specification); forming the aforementioned protective film by energy line hardening the aforementioned first laminated film or the aforementioned protective film forming film in the first laminated composite film to form the aforementioned protective film, and stacking the aforementioned protective film and wafer in the thickness direction of these layers to form the second laminated film; or forming... The step of sequentially stacking the aforementioned support layer, protective film, and wafer in the thickness direction of these layers to form a second laminated composite film (sometimes referred to as the "hardening step" in this specification); with a dicing blade provided on the protective film side of the aforementioned second laminated film, the aforementioned wafer in the aforementioned second laminated film is diced to cut the aforementioned protective film, thereby producing a third laminated film in which multiple aforementioned wafers with protective films are fixed on the aforementioned dicing blade; or by dicing the aforementioned second laminated composite film... The steps involved in creating a third laminated composite wafer by cutting the protective film off the aforementioned wafer to fabricate multiple protective film-bearing wafers fixed onto the aforementioned support sheet (sometimes referred to as the "dicing step" in this specification); and the steps involved in picking up the protective film-bearing wafers from the aforementioned dicing wafer in the third laminated composite wafer, either by detaching them from the aforementioned support sheet (sometimes referred to as the "pickup step" in this specification).

The following describes, with reference to the figures, a method for manufacturing a wafer with a protective film when a protective film forming film that does not constitute a protective film forming composite is attached to the inner surface of the wafer (sometimes referred to as "manufacturing method 1" in this specification), and a method for manufacturing a wafer with a protective film when a protective film forming film in a protective film forming composite is attached to the inner surface of the wafer (sometimes referred to as "manufacturing method 2" in this specification).

[Manufacturing Method 1] Figure 6 is a cross-sectional view schematically illustrating Manufacturing Method 1. Here, Manufacturing Method 1 will be explained using, for example, the protective film forming film 13 shown in Figure 1. In the aforementioned attachment step of Manufacturing Method 1, as shown in Figure 6(a), the protective film forming film 13 is attached to the inner surface 9b of the wafer 9 to create a first laminated film 601 formed by stacking the protective film forming film 13 and the wafer 9 in the thickness direction of these layers. The first surface 13a of the protective film forming film 13 is attached to the inner surface 9b of the wafer 9. A second release film 152 is provided on the second surface 13b of the protective film forming film 13. This indicates the case where the first peel film 151 is removed from the protective film forming film 13 as shown in Figure 1, and the first surface 13a of the protective film forming film 13 is attached to the inner surface 9b of the wafer 9. However, it is also possible to remove the second peel film 152 from the protective film forming film 13 as shown in Figure 1, and attach the second surface 13b of the protective film forming film 13 to the inner surface 9b of the wafer 9.

The protective film 13 can be applied to the wafer 9 using known methods. For example, the protective film 13 can also be applied to the wafer 9 while being heated.

Then, in the aforementioned curing step of manufacturing method 1, a protective film 13' is formed by energy line curing of the protective film forming film 13 in the first laminated film 601, as shown in FIG. 6(b). A second laminated film 602 is formed by laminating the protective film 13' and the wafer 9 in the thickness direction of these layers. The symbol 13a' indicates the surface of the protective film 13' that was once the first surface 13a of the protective film forming film 13 (sometimes referred to as "first surface" in this specification). The symbol 13b' indicates the surface of the protective film 13' that was once the second surface 13b of the protective film forming film 13 (sometimes referred to as "second surface" in this specification).

In the aforementioned curing step, a protective film 13' is formed by irradiating the protective film forming film 13 from the outside of the protective film forming film 13 side of the first laminated film 601, passing through the second peeling film 152. Alternatively, in the aforementioned curing step, the second peeling film 152 can be removed from the protective film forming film 13 in the first laminated film 601, exposing the second surface 13b of the protective film forming film 13, and then irradiating the protective film forming film 13 with energy rays.

The irradiation conditions of the energy lines in the aforementioned hardening step are as described above.

Alternatively, the protective film 13 shown in FIG6(a) can be laser-marked by laser irradiation across the second peeling membrane 152 (penetrating the second peeling membrane 152), or the protective film 13' shown in FIG6(b) can be laser-marked by laser irradiation across the second peeling membrane 152 (penetrating the second peeling membrane 152).

Then, in the aforementioned segmentation step of manufacturing method 1, the second peel-off film 152 is first removed from the protective film 13' in the second laminated film 602. Furthermore, one side (sometimes referred to as the "first side") 8a of the cutting disc 8 shown in FIG. 6(c) is attached to the second side 13b' of the newly exposed protective film 13'. The cutting disc 8 shown here comprises: a substrate 81, and an adhesive layer 82 disposed on one side 81a of the substrate 81; the adhesive layer 82 of the cutting disc 8 is attached to the protective film 13'. The side of the adhesive layer 82 facing the protective film 13' (sometimes referred to as the "first side") 82a is identical to the first side 8a of the cutting disc 8.

The cutting disc 8 can also be a known cutting disc. For example, the substrate 81 can also be the same as the substrate in the composite sheet for forming the protective film described above, and the adhesive layer 82 can also be the same as the adhesive layer in the composite sheet for forming the protective film described above.

Here, it is indicated that in the case of using a cutting disc 8 having a substrate 81 and an adhesive layer 82, other types of cutting discs, such as those made solely of a substrate, can also be used in the aforementioned slitting step.

Then, in the aforementioned slicing step, as shown in Figure 6(d), with the dicing blade 8 disposed on the protective film 13' side of the second laminated film 602, the wafer 9 in the second laminated film 602 is sliced, and the protective film 13' is cut off. The wafer 9 is monolithized by slicing, becoming multiple chips 90.

The dicing of wafer 9 and the cutting of the protective film 13' can be performed using known methods. For example, various cutting methods can be used, such as blade cutting, laser cutting, or water jet cutting with water containing abrasive, to continuously dice wafer 9 and cut the protective film 13'. Regardless of the cutting method, the protective film 13' is cut along the outer periphery of the wafer 90.

Thus, by slicing wafer 9 and cutting the protective film 13', multiple wafers 901 with protective films can be obtained, each having a wafer 90 and a protective film (referred to as "protective film" in this specification) 130' disposed on the inner surface 90b of the wafer 90. The symbol 130b' indicates the second surface 13b' of the protective film 130' that was once the protective film 13' (sometimes referred to as "second surface" in this specification).

In the aforementioned slitting step of manufacturing method 1, the third laminated film 603 is formed by fixing multiple protective film wafers 901 onto the dicing plate 8 in the above manner.

Then, in the aforementioned pick-up step of manufacturing method 1, as shown in FIG. 6(e), the wafer 901 with the protective film in the third laminated film 603 is picked up by peeling it off from the dicing die 8. In the aforementioned pick-up step, a peeling occurs between the second surface 130b' of the protective film 130' in the wafer 901 with the protective film and the first surface 82a of the adhesive layer 82 in the dicing die 8.

This section illustrates the use of a vacuum clamp or similar detachment method 7 to detach the protective film-coated wafer 901 in the direction of arrow P. Furthermore, a cross-sectional view of the detachment method 7 is omitted here. The protective film-coated wafer 901 can be picked up using known methods.

When the adhesive layer 82 is energy-line hardened, it is preferable that, during the aforementioned pick-up step, the adhesive layer 82 is hardened by irradiating it with an energy line to form a hardened material (not shown), and then the wafer 901 with the protective film is peeled off from the dicing die 8. In this case, during the aforementioned pick-up step, peeling occurs between the protective film 130' in the wafer 901 and the hardened adhesive layer 82 in the dicing die 8. In this case, because the adhesive force between the hardened adhesive layer 82 and the protective film 130' is less than the adhesive force between the adhesive layer 82 and the protective film 130', the wafer 901 with the protective film can be picked up more easily.

In the aforementioned pickup step, the irradiation conditions for the energy lines of the adhesive layer 82 can also be, for example, the same as the irradiation conditions for the energy lines of the protective film forming film 13 in the aforementioned curing step.

In this specification, even after the energy line curing adhesive layer has been cured, as long as the laminate structure formed by the hardened substrate and the energy line curing adhesive layer is maintained, the laminate structure is still referred to as a "cutting disc".

On the other hand, when the adhesive layer 82 is not line-cured, the chip 901 with the protective film can be directly peeled off from the adhesive layer 82. Since the adhesive layer 82 does not need to be cured, the process for picking up the chip 901 with the protective film can be simplified. Even if the adhesive layer 82 is line-cured, picking up the chip 901 with the protective film without curing the adhesive layer 82 allows for a simplified process for picking up the chip 901 with the protective film.

In the aforementioned picking step, this picking of the protective film-covered wafers 901 is performed on all the target wafers 901.

In manufacturing method 1, by proceeding up to the aforementioned picking step, the target chip 901 with a protective film can be obtained.

In manufacturing method 1, since the protective film is formed using the aforementioned protective film, during the reflow step when the chip 901 with the protective film is mounted on the circuit substrate, the seepage of the protective film surface is suppressed. Therefore, when the laser marking is on the protective film, the deterioration of the laser marking can be suppressed even after the reflow step.

[Manufacturing Method 2] Figure 7 is a cross-sectional view schematically illustrating Manufacturing Method 2. Here, Manufacturing Method 2 is explained using, for example, the protective film forming composite sheet 101 shown in Figure 2. In the aforementioned attachment step of Manufacturing Method 2, as shown in Figure 7(a), the protective film forming film 13 of the protective film forming composite sheet 101 is attached to the inner surface 9b of the wafer 9 to create a first laminated composite sheet 501 formed by sequentially stacking the support sheet 10, the protective film forming film 13, and the wafer 9 in the thickness direction of these layers. This is also the same as in Manufacturing Method 1, where the first surface 13a of the protective film forming film 13 of the protective film forming composite sheet 101 is attached to the inner surface 9b of the wafer 9.

When attaching the protective film forming film 13 in the protective film forming composite 101 to the wafer 9, it can be done by known methods. For example, the protective film forming film 13 can also be attached to the wafer 9 while being heated.

Then, in the aforementioned hardening step of manufacturing method 2, a protective film 13' is formed by energy line hardening of the protective film forming film 13 in the first laminated composite 501, as shown in FIG7(b), to make a second laminated composite 502 composed of the support sheet 10, the protective film 13' and the wafer 9 sequentially laminated in the thickness direction of these layers.

In the aforementioned hardening step, an energy line is irradiated onto the protective film forming film 13 from the outside of the support sheet 10 side of the first laminated composite sheet 501, passing through the support sheet 10 (penetrating the support sheet 10), to form the protective film 13'.

The aforementioned curing step, except for replacing the first laminated film 601 with the first laminated composite sheet 501, can be performed in the same manner as the curing step in manufacturing method 1.

The second laminated composite sheet 502 obtained by the aforementioned curing step has the same structure as the second laminated film 602 and the laminate of the cutting sheet 8 in the slitting step of manufacturing method 1. When the cutting sheet 8 is the same as the support sheet 10, the second laminated composite sheet 502 is the same as the aforementioned laminate.

Then, in the aforementioned slitting step of manufacturing method 2, as shown in FIG7(c), the wafer 9 in the second stacked composite 502 is slitted and the protective film 13' is cut off. The wafer 9 is monolithized by slitting into multiple chips 90.

The aforementioned slitting step, except that it replaces the laminated material of the second laminated film 602 and the dicing wafer 8 with a second laminated composite wafer 502, can be performed in the same manner as the slitting step in manufacturing method 1. Even in manufacturing method 2, regardless of the slitting method, the protective film 13' is slid along the outer periphery of the wafer 90.

Thus, by dicing wafer 9 and cutting the protective film 13', multiple wafers 901 with protective films are obtained, each having a wafer 90 and a cut protective film 130' disposed on the inner surface 90b of the wafer 90. These wafers 901 with protective films obtained in the dicing step described above in manufacturing method 2 are the same as those wafers 901 with protective films obtained in the dicing step in manufacturing method 1.

Alternatively, the protective film 13 shown in FIG7(a) can be laser-marked by laser irradiation through the support sheet 10 (penetrating the support sheet 10), or the protective film 13' shown in FIG7(b) can be laser-marked by laser irradiation through the support sheet 10 (penetrating the support sheet 10).

In the aforementioned dicing step of manufacturing method 2, the third laminated composite sheet 503, consisting of multiple protective film-bearing wafers 901 fixed on the support sheet 10, is fabricated using the above method. The third laminated composite sheet 503 has the same structure as the third laminated film 603 obtained in the dicing step of manufacturing method 1. When the dicing wafer 8 is identical to the support sheet 10, the third laminated composite sheet 503 is identical to the third laminated film 603.

Then, in the aforementioned pick-up step of manufacturing method 2, as shown in FIG. 7(d), the wafer 901 with the protective film in the third laminated composite 503 is picked up by peeling it off from the support sheet 10. In the aforementioned pick-up step, a peeling occurs between the second surface 130b' of the protective film 130' in the wafer 901 with the protective film and the first surface 12a of the adhesive layer 12 in the support sheet 10.

The aforementioned pick-up step, except that the third laminated composite sheet 503 is used instead of the third laminated film 603, can be performed in the same manner as the pick-up step in manufacturing method 1.

For example, when the adhesive layer 12 is energy-line hardened, it is preferable that, during the aforementioned pickup step, the adhesive layer 12 is hardened by irradiating it with an energy line to form a hardened material (not shown), and then the protective film-bearing wafer 901 is peeled off from the support sheet 10. In this case, during the aforementioned pickup step, a peeling occurs between the protective film 130' in the protective film-bearing wafer 901 and the hardened adhesive layer 12 in the support sheet 10. In this case, because the adhesive force between the hardened adhesive layer 12 and the protective film 130' is less than the adhesive force between the adhesive layer 12 and the protective film 130', the protective film-bearing wafer 901 can be picked up more easily.

On the other hand, when the adhesive layer 12 is not line-cured, the chip 901 with the protective film can be directly peeled off from the adhesive layer 12. Since curing of the adhesive layer 12 is not required, the chip 901 with the protective film can be picked up using a simplified procedure. Even when the adhesive layer 12 is line-cured, the chip 901 with the protective film can be picked up without curing the adhesive layer 12, thereby simplifying the process.

In manufacturing method 2, by proceeding to the aforementioned picking step, the target chip 901 with a protective film can be obtained. The chip 901 with a protective film obtained by manufacturing method 2 is the same as the chip 901 with a protective film obtained by manufacturing method 1.

In manufacturing method 2, since the aforementioned protective film forming composite sheet is used, during the reflow step when the chip 901 with the protective film is mounted on the circuit substrate, the seepage of the protective film surface is suppressed. Therefore, when laser marking is performed on the protective film, the deterioration of the laser marking can be suppressed even after the reflow step.

Up to this point, manufacturing method 2 has been described when using the protective film forming composite sheet 101 shown in FIG. 2. However, in manufacturing method 2, protective film forming composite sheets of this embodiment other than the protective film forming composite sheet 101, such as the protective film forming composite sheet 102, protective film forming composite sheet 103, or protective film forming composite sheet 104 shown in FIG. 3 to 5, can also be used.

◇Method for Manufacturing a Substrate Device (Method for Using a Wafer with a Protective Film) After obtaining a wafer with a protective film using the above-described manufacturing method, the substrate device can be manufactured in the same manner as the previous substrate device manufacturing method, except that it replaces the previous wafer with a protective film and is used instead.

For example, the following method of manufacturing a substrate device can be cited: through a reflow step (using a reflow oven equipped with a halogen heater to heat a circuit substrate on which a chip with a protective film obtained by forming the aforementioned protective film is mounted, thereby melting the protruding electrodes on the chip with the protective film), the electrical connection between the protruding electrodes and the bonding pads on the circuit substrate is strengthened.

The substrate apparatus of this embodiment, by using the aforementioned protective film forming film or protective film forming composite sheet, suppresses surface seepage of the protective film caused by the reflow step. Therefore, the substrate apparatus of this embodiment is superior to previous substrate apparatuses in terms of superior design of the protective film surface and suppression of laser marking degradation. [Example]

The invention will now be described in more detail with reference to specific embodiments. However, the invention is not limited to the embodiments shown below.

[Raw Materials for Resin Manufacturing] The formal names of the raw materials for manufacturing the resins abbreviated in this embodiment and comparative examples are as follows: BA: n-Butyl acrylate MA: Methyl acrylate ACrMO: 4-Acryloylphosphonic acid HEA: 2-Hydroxyethyl acrylate 2EHMA: 2-Ethylhexyl methacrylate

[Raw Materials for Manufacturing Protective Film Forming Components] The raw materials used to manufacture the protective film forming components are as follows: [Energy-curing component (a)] (a)-1: Carbamate acrylate (KJ Chemicals, "Quickcure 8100EA70") (a)-2: ε-caprolactone-modified tri-(2-acryloxyethyl) isocyanurate (Shin-Nakamura Chemical Industry Co., Ltd., "A-9300-1CL", a 3-functional UV-curing compound) [Acrylic resin without energy-curing groups (b)] (b)-1: Acrylic resin of a copolymer of BA (33 parts by mass), MA (27 parts by mass), ACrMO (25 parts by mass), and HEA (15 parts by mass) (weight average molecular weight (700,000), glass transition temperature 2°C) (b)-2: Acrylic resin of a copolymer of MA (85 parts by weight) and HEA (15 parts by weight) (weight average molecular weight 400,000, glass transition temperature 6°C) [Photopolymerization Initiator (c)] (c)-1: 2-(dimethylamino)-1-(4-mofolinphenyl)-2-benzyl-1-butanone (manufactured by BASF, "Omnirad (registered trademark) 369") (c)-2: 2-Hydroxyl-1-(4-(4-(2-hydroxy-2-methylpropyl)benzyl)phenyl)-2-methylpropane-1-one (manufactured by BASF, "Omnirad (registered trademark) 127D") (c)-3: 2-Hydroxyl-2-methyl-1-phenylpropane-1-one (BASF Omnirad 1173) (c)-4: 1-Hydrocyclohexyl-phenylone (BASF Omnirad 184) [Inorganic Filler (d)] (d)-1: Silica filler (fused silica filler, average particle size 8 μm) [Colorant (g)] (g)-1: 32 parts by weight of black pigment (Pigment Blue 15:3), 18 parts by weight of isoindolinone yellow pigment (Pigment Yellow 139), and anthraquinone red pigment (Pigment Red) 177) 50 parts by weight are mixed to obtain a pigment by pigmentation in which the total amount of the three pigments / the amount of styrene-acrylic resin = 1/3 (mass ratio). (g)-2: Organic black pigment (Dainichi Seika Co., Ltd. "6377 Black") [General Additives (z)] (z)-1: Hydroxyphenyl triazine UV absorber (BASF Co., Ltd. "Tinuvin (registered trademark) 479")

[Manufacturing of protective film forming film, composite film for protective film forming, and wafer with protective film] [Example 1] [Manufacturing of component (IV)-1 for protective film forming] The energy line curing component (a)-1 (10.1 parts by mass), the energy line curing component (a)-2 (12.4 parts by mass), the acrylic resin (b)-1 (14.7 parts by mass) without energy line curing groups, the photopolymerization initiator (c)-1 (0.1 parts by mass), the photopolymerization initiator (c)-2 (0.5 parts by mass), the inorganic filler (d)-1 (58.4 parts by mass), the colorant (g)-1 (3 parts by mass), and the general additive (z)-1 (0.8 parts by mass) are melted or dispersed in methyl ethyl ketone and stirred at 23°C to obtain an energy line curing protective film forming component (IV)-1 with a total concentration of 45% by mass of all components other than the solvent. Furthermore, all the amounts of components other than the solvent shown here are solvent-free target substances.

[Manufacturing of Protective Film Forming Film] A single-sided release film (second release film, manufactured by Lintec Corporation, "SP-PET382150", 38μm thick) made of polyethylene terephthalate (PET) was subjected to a polysiloxane treatment. The protective film forming component (IV)-1 obtained above was applied to the release-treated side prior to the release film and dried at 100°C for 2 minutes, thereby manufacturing a 25μm thick energy line curing protective film forming film.

Furthermore, by attaching the peeling treatment surface of the peeling membrane (first peeling membrane, manufactured by Lintec Corporation "SP-PET381031", thickness 38μm) to the exposed surface of the obtained protective film forming film that does not have the second peeling membrane, a protective film forming film with a peeling membrane is obtained, which consists of a protective film forming film, a first peeling membrane disposed on one side of the aforementioned protective film forming film, and a second peeling membrane disposed on the other side of the aforementioned protective film forming film.

[Preparation of Adhesive Composition (I-4)-1] A non-energy-line curable adhesive composition (I-4)-1 was prepared, comprising acrylic resin (100 parts by weight), a toluene diisocyanate crosslinker (TOYOCHEM, "BHS8515") (10.0 parts by weight as a crosslinker), a hexamethylene diisocyanate crosslinker (Tosoh, "Coronate HL") (7.5 parts by weight as a crosslinker), and methyl ethyl ketone as a solvent. The aforementioned acrylic resin is a copolymer with a weight average molecular weight of 600,000, formed by copolymerizing 2EHMA (80 parts by weight) and HEA (20 parts by weight).

[Manufacturing of Support Sheet] A release film (Lintec Corporation "SP-PET381031", 38μm thick) was prepared by polysiloxane treatment on one side of a polyethylene terephthalate (PET) film. Before the release film, the aforementioned adhesive composition (I-4)-1 was applied to the release-treated side and dried at 100°C for 2 minutes, thereby forming a 5μm thick non-energy-line-curing adhesive layer. Then, a polypropylene film (80 μm thick, colorless) serving as the substrate is laminated onto the exposed surface of the adhesive layer, thereby creating a support sheet with a release membrane, formed by sequentially laminating the substrate, adhesive layer, and release membrane in the thickness direction of these layers.

[Manufacturing of Composite Sheet for Protective Film Formation] The release film is removed from the support sheet obtained above. Furthermore, the second release film is removed from the protective film forming film obtained above. Then, by attaching the exposed surface of the adhesive layer resulting from the removal of the release film to the exposed surface of the protective film forming film resulting from the removal of the second release film, a composite sheet for protective film formation is manufactured, consisting of a substrate, an adhesive layer, a protective film forming film, and a first release film sequentially laminated in the thickness direction of these layers.

[Manufacturing of a Wafer with a Protective Film] In the protective film forming composite obtained above, the first peel film is removed from the protective film forming film. Then, using a bonding device (AdwillRAD-2700, Lyndeco), the newly exposed surface of the protective film forming film is placed against the ♯2000 grinding surface of a silicon wafer (300μm thick), and heated lamination is performed under conditions of a bonding temperature of 70°C, a bonding pressure of 0.3MPa, and a bonding speed of 0.3mm/s, so that the protective film forming composite is bonded to the silicon wafer (bonding step). The first laminated composite is manufactured in this manner.

Then, using an ultraviolet irradiation device (LINDECO "RAD2000m/8"), the protective film is irradiated twice through the aforementioned substrate and adhesive layer under conditions of 200mW/ ^cm² illuminance and 300mJ/ ^cm² light intensity, thereby hardening the protective film to form a protective film (hardening step). The second laminated composite sheet is produced in this manner.

Then, in the second laminated composite, the silicon wafer is diced into 3mm x 3mm silicon wafers using a dicing device (DISCO's "DFD6362"). The protective film is also cut along the outer periphery of the silicon wafers to create multiple wafers with protective films (dicing step). Multiple silicon wafers with protective films are then fixed onto a support sheet to form the third laminated composite. These silicon wafers with protective films are each dried at 125°C for 24 hours.

Then, the silicon wafer with the protective film in the aforementioned third laminated composite is picked up by peeling it from the support sheet (picking step). The target wafer with the protective film is obtained in this way.

[Example 2] [Manufacturing of Protective Film Forming Component (IV)-2] Except for replacing acrylic resin (b)-1 (14.7 parts by mass) which lacks energy-curing groups with acrylic resin (b)-2 (14.7 parts by mass), replacing photopolymerization initiator (c)-1 (0.1 parts by mass) and photopolymerization initiator (c)-2 (0.5 parts by mass) with photopolymerization initiator (c)-3 (0.6 parts by mass), and replacing colorant (g)-1 (3 parts by mass) with colorant (g)-2 (3 parts by mass), protective film forming component (IV)-2 is manufactured by the same method as in Example 1.

[Manufacturing of Protective Film Forming Film, Protective Film Forming Composite, and Wafer with Protective Film] Except for using Protective Film Forming Composition (IV)-2 instead of Protective Film Forming Composition (IV)-1, the protective film forming film is manufactured using the same method as in Embodiment 1. Furthermore, except for using the protective film forming film, the protective film forming composite and the wafer with protective film are manufactured using the same method as in Embodiment 1.

[Example 3] [Manufacturing of Protective Film Forming Composition (IV)-3] Except for replacing 12.4 parts by mass of the energy-curing component (a)-2 with 7.4 parts by mass, and replacing 14.7 parts by mass of the acrylic resin (b)-1 (which does not have energy-curing groups) with 19.7 parts by mass, the protective film forming composition (IV)-3 is manufactured using the same method as that used for protective film forming composition (IV)-1 in Example 1.

[Manufacturing of Protective Film Forming Film, Protective Film Forming Composite, and Wafer with Protective Film] Except for using Protective Film Forming Composition (IV)-3 instead of Protective Film Forming Composition (IV)-1, the protective film forming film is manufactured using the same method as in Embodiment 1. Furthermore, except for using this protective film forming film, the protective film forming composite and the wafer with protective film are manufactured using the same method as in Embodiment 1.

[Comparative Example 1] [Manufacturing of Component (X)-1 for Protective Film Formation] Except for replacing photopolymerization initiator (c)-3 (0.6 parts by mass) with photopolymerization initiator (c)-4 (0.6 parts by mass), component (X)-1 for protective film formation is manufactured using the same method as component (IV)-1 for protective film formation in Example 1.

[Manufacturing of Protective Film Forming Film, Protective Film Forming Composite, and Wafer with Protective Film] Except for using protective film forming composition (X)-1 instead of protective film forming composition (IV)-1, the protective film forming film is manufactured using the same method as in Embodiment 1. Furthermore, except for using this protective film forming film, the protective film forming composite and the wafer with protective film are manufactured using the same method as in Embodiment 1.

[Comparative Example 2] [Manufacturing of Component (X)-2 for Protective Film Formation] Except for replacing photopolymerization initiator (c)-3 (0.6 parts by mass) with photopolymerization initiator (c)-2 (0.6 parts by mass), component (X)-2 for protective film formation is manufactured using the same method as that used for component (IV)-1 for protective film formation in Example 1.

[Manufacturing of Protective Film Forming Film, Protective Film Forming Composite, and Wafer with Protective Film] Except for using protective film forming composition (X)-2 instead of protective film forming composition (IV)-1, the protective film forming film is manufactured using the same method as in Embodiment 1. Furthermore, except for using this protective film forming film, the protective film forming composite and the wafer with protective film are manufactured using the same method as in Embodiment 1.

[Comparative Example 3] [Manufacturing of Protective Film Forming Composition (X)-3] Except for omitting the use of the energy-curing component (a)-1, and replacing 12.4 parts by mass of the energy-curing component (a)-2 with 10.1 parts by mass, and replacing 14.7 parts by mass of the acrylic resin (b)-1 (which does not have energy-curing groups) with 27.1 parts by mass, the protective film forming composition (X)-3 is manufactured using the same method as that used for protective film forming composition (IV)-1 in Example 1.

[Manufacturing of Protective Film Forming Film, Protective Film Forming Composite, and Wafer with Protective Film] Except for using protective film forming composition (X)-3 instead of protective film forming composition (IV)-1, the protective film forming film is manufactured using the same method as in Embodiment 1. Furthermore, except for using this protective film forming film, the protective film forming composite and the wafer with protective film are manufactured using the same method as in Embodiment 1.

[Evaluation of Protective Film Forming Membrane] [Determination of Storage Elastic Modulus of Protective Film Forming Membrane] In each embodiment and comparative example, using the multiple protective film forming membranes with peelable membranes obtained above, while removing the first or second peelable membrane of these protective film forming membranes, the exposed surfaces of the protective film forming membranes were bonded together to produce a test piece (protective film forming membrane test piece) of multiple protective film forming membrane stacks (thickness 200 μm, length in the stretching direction of the aforementioned stretching mode 30 mm). Then, using a dynamic viscoelasticity automatic measuring device (RHEOVIBRON DDV-01FP, A&D Corporation), the storage elastic modulus E’ of the protective film forming test sheet was measured within a temperature range of -10℃ to 140℃ under the following conditions: tensile method (tensile mode), clamp distance 20mm, amplitude 5μm, frequency 11Hz, heating rate 3℃/min, and constant heating.

[Determination of the storage elastic modulus of the protective film] In each embodiment and comparative example, using the multiple protective film forming films with peelable membranes obtained above, while removing the first or second peelable membrane of these protective film forming films with peelable membranes, the exposed surfaces of the protective film forming films are bonded together to produce a multi-layered protective film forming film (thickness 50 μm). Then, the laminate was irradiated twice with ultraviolet light at a wavelength of 365nm on both sides using an ultraviolet irradiation device (LINTEC Corporation "RAD2000m/8") under conditions of 200mW/ ^cm² illuminance and 300mJ/ ^cm² light intensity, thereby curing the protective film to form a protective film. After obtaining multiple laminates of protective film in the above manner, a test piece (protective film test piece) with a width of 5mm (thickness 50μm) was made. Then, using a dynamic mechanical analysis apparatus (TA Instruments "DMAQ800"), the storage elastic modulus E' of the protective film test piece was determined within a temperature range of 0°C to 300°C under the following conditions: tensile method (tensile mode), clamp distance 20 mm, amplitude 5 μm, frequency 11 Hz, heating rate 3°C/min, and constant heating.

[Determination of weight reduction rate _ΔW1 (%) after heating at 130°C for 2 hours] For the protective film formed in Examples 1 to 3 and Comparative Examples 1 to 3, a Shimadzu DTG-60 TG/DTA simultaneous measuring device was used. Approximately 10 mg of test tablets were heated from 25°C to 130°C at a heating rate of 10°C/min, and then heated at 130°C for 2 hours. The weight reduction rate ( _ΔW1 ) (weight %) was calculated from the weight of the protective film formed before heating (W0) and the weight of the protective film formed after heating ( _W1 ) using the following formula ( ₁ ). The results are shown in Tables 1 and 2. _ΔW1 = ( _W0 - _W1 ) / _W0 × 100... (1)

[Determination of weight reduction rate _ΔW2 (%) after two UV irradiations] For the protective film forming films of Examples 1 to 3 and Comparative Examples 1 to 3, a RAD2000 UV irradiation device manufactured by Lintec Corporation was used to irradiate 150mm×150mm test pieces twice under the conditions of illuminance of 200mW/ ^cm2 and light intensity of 300mJ/ ^cm2 . The weight reduction rate (ΔW2) (weight %) was calculated from the weight of the protective film forming film before UV irradiation ( _W0 ) and the weight of the protective film forming film after UV irradiation ( _W2 ) using the following formula ( ₂ ). The results are shown in Tables 1 and 2. _ΔW2 = ( _W0 - _W2 ) / _W0 × 100... (2)

[Determination of weight loss rate ( _ΔW3 ) (%) after two UV irradiations and heating at 260°C for 10 min] Regarding the protective film formed in Examples 1 to 3 and Comparative Examples 1 to 3, a RAD2000 UV irradiation device manufactured by Lintec Corporation was used to irradiate each 150mm × 150mm test piece twice with UV irradiation at an illuminance of 200mW/cm² and ^a light intensity of 300mJ/ ^cm² . Furthermore, a DTG-60 TG/DTA simultaneous measurement device manufactured by Shimadzu Corporation was used to heat the film from 25°C to 260°C at a heating rate of 10°C/min, and then heat it at 260°C for 10 minutes. The weight reduction rate ( _ΔW3 ) (weight %) was calculated using the following formula (3) based on the weight of the protective film before UV irradiation ( _W0 ) and the weight of the protective film after heating (W3). The results are shown in Tables 1 and 2. _ΔW3 = ( _W0 - _W3 ) / _W0 × 100... ( ₃ )

[Determination of Gel Content of Components Other Than Inorganic Fillers] Regarding the protective film forming films of Examples 1 to 3 and Comparative Examples 1 to 3, a RAD2000 UV irradiation device manufactured by Lintec Corporation was used to irradiate the films twice with a wavelength of 365nm under conditions of 200mW/ ^cm² illuminance and 300mJ/ ^cm² light intensity. Then, the protective film forming films after UV irradiation were cut into 50mm×100mm sizes to form test samples, which were then covered with 100mm×150mm nylon mesh sheets (mesh size 200) and stapled to form test pieces. The mass _M1 of the test piece, the mass _M2 of the nylon mesh, and the mass _M3 of the stapler needle were weighed using a precision balance. Furthermore, during the process of pre-determining the mass of the inorganic portion of the test piece's mass _M1 from the mass of the residue portion after the protective film forming film has been calcined at 600°C for 30 minutes, it was confirmed that the mass of the inorganic portion was equal to the mass _M4 of the inorganic filler material (d) in the formulation of the protective film forming film in Examples 1 to 3 and Comparative Examples 1 to 3.

Then, the test piece was immersed in ethyl acetate (100 mL) at 25°C for 48 hours. The insoluble matter of the protective film after UV irradiation, the nylon mesh, and the stapler needle were removed together and dried at 90°C for 3 hours. Then, it was placed at 23°C and 50% relative humidity for 1 hour to adjust the humidity. Then, the mass _M5 of the immersed and dried test piece was weighed with a precision balance. And, the gel fraction of the components other than the inorganic filler was calculated by the following formula (4). The results are shown in Table 1 and Table 2. ΔG＝( _M5 － _M2 － _M3 － _M4 )／( _M1 － _M2 － _M3 － _M4 )×100・・・(4)

[Determination of Gloss Reduction Rate] Test pieces were prepared by peeling the support sheet from each second-layer laminated composite sheet obtained from the protective film forming films of Examples 1 to 3 and Comparative Examples 1 to 3. The gloss value (gloss value of the protective film after energy line curing (G1)) of the exposed protective film surface was measured using a gloss meter (Nippon Denshoku Kogyo Co., Ltd. "VG7000") at an incident angle of 60°. Then, each test piece was heated at 260°C for 10 minutes. Afterward, the gloss value of the protective film surface was measured under the same conditions as the measurement of the gloss value (G1) before heating (gloss value of the protective film after 10 minutes of heat treatment (G2)). The gloss reduction rate (%) was calculated using the following formula (5). Gloss reduction rate (%) = (G1 - G2) / G1 × 100...(5) The results of the gloss value before heating (G1), the gloss value after heating (G2), and the gloss reduction rate (%) are shown in Tables 1 and 2.

In addition, based on visual observation, as the amount of exudation on the surface of the protective film increases, the gloss value tends to decrease. Therefore, those with a gloss value reduction rate of less than 30% are evaluated as having less and better exudation on the surface of the protective film (A), while those with a gloss value reduction rate of more than 30% are evaluated as having more and worse exudation on the surface of the protective film (C), as shown in Tables 1 and 2.

[Table 1] Implementation Examples 1 2 3 Protective film formation film Ingredients (Quality Department) Energy line hardening component (a) (a)-1 10.1 10.1 10.1 (a)-2 12.4 12.4 7.4 Acrylic resins without energy line hardening groups (b) (b)-1 14.7 - 19.7 (b)-2 - 14.7 - Photopolymerization initiator (c) (c)-1 0.1 - 0.1 (c)-2 0.5 - 0.5 (c)-3 - 0.6 - Inorganic filling materials (d) (d)-1 58.4 58.4 58.4 Colorant (g) (g)-1 3 - 3 (g)-2 - 3 - General Additives (z) (z)-1 0.8 0.8 0.8 total 100 100 100 Weight loss rate ( _ΔW1 ) after heat treatment at 130°C for 2 hours (by weight %) 1.1 1.3 1.1 Weight loss rate ( _ΔW² ) after two treatments with ultraviolet (300 mJ/ ^cm² ) irradiation (by weight %) 0.0 0.1 0.0 Weight loss rate ( _ΔW3 ) (wt%) after irradiation with ultraviolet light (300 mJ/ ^cm2 ) twice and heat treatment at 260°C for 10 min. 2.0 2.4 2.8 Gel fraction (ΔG) (%) of components other than inorganic fillers 95.2 92.8 73.6 Evaluation results Gloss value before heating (G1) 85.0 85.0 85.2 Gloss level after heating (G2) 77.4 72.1 62.7 Gloss reduction rate (%) 9.0 15.2 26.5 Exudation on the surface of the protective film A A A

[Table 2] Comparative example 1 2 3 Protective film formation film Ingredients (Quality Department) Energy line hardening component (a) (a)-1 10.1 10.1 10.1 (a)-2 12.4 12.4 - Acrylic resins without energy line hardening groups (b) (b)-1 - - 27.1 (b) - 2 14.7 14.7 - Photopolymerization initiator (c) (c)-1 - - 0.1 (c)-2 - 0.6 0.5 (c)-4 0.6 - - Inorganic filling materials (d) (d)-1 58.4 58.4 58.4 Colorant (g) (g)-1 - - 3 (g)-2 3 3 - General Additives (z) (z)-1 0.8 0.8 0.8 total 100 100 100 Weight loss rate ( _ΔW1 ) after heat treatment at 130°C for 2 hours (by weight %) 1.1 1.1 1.2 Weight loss rate ( _ΔW² ) after two treatments with ultraviolet (300 mJ/ ^cm² ) irradiation (by weight %) 0.0 0.0 0.0 Weight loss rate ( _ΔW3 ) (wt%) after irradiation with ultraviolet light (300 mJ/ ^cm2 ) twice and heat treatment at 260°C for 10 min. 3.1 3.3 4.0 Gel fraction (%) of components other than inorganic fillers 52.0 38.2 27.9 Evaluation results Gloss value before heating (G1) 85.1 85.0 84.8 Gloss level after heating (G2) 57.5 55.3 39.0 Gloss reduction rate (%) 32.4 35.0 54.0 Exudation on the surface of the protective film C C C

As can be clearly seen from the above results, the protective film formed in Examples 1 to 3 contains an energy-curing component (a), and the weight loss rate after energy-curing and heat treatment at 260°C for 10 minutes is less than 3.0%, and the gel content of components other than inorganic fillers after energy-curing is more than 60%. Therefore, the decrease in gloss value under the general conditions of the reflow step, i.e., heat treatment at 260°C for 10 minutes, is minimal, and the exudation of the protective film formed by energy-curing is suppressed due to the reflow step.

The aforementioned protective film forming test piece has a storage elastic modulus E' ₇₀ of 1.0 MPa (Example 1), 1.0 MPa (Example 2), and 0.9 MPa (Example 3) at 70°C, all of which have better characteristics for wafer adhesion.

The aforementioned protective film test pieces have a storage elastic modulus E' ₁₃₀ of 50 MPa (Example 1), 40 MPa (Example 2), and 25 MPa (Example 3) at 130°C, which are all considered to be good properties for protective films.

In contrast, the protective film formed in Comparative Examples 1 to 3 showed a weight reduction rate exceeding 3.0% after energy line curing and heat treatment at 260°C for 10 minutes, and the gel content of components other than inorganic fillers after energy line curing was less than 60%. The protective film formed in Comparative Examples 1 to 3 showed a significant decrease in gloss value under typical reflow conditions (i.e., heat treatment at 260°C for 10 minutes), raising concerns about leakage due to the reflow process. [Industry Applicability]

This invention can be used in the manufacture of various substrate devices, including semiconductor devices.

7: Detachment method 8: Cutting disc 8a: One side of the cutting disc (first side) 9: Wafer 9b: Inner surface of the wafer 10, 20: Supporting sheet 10a, 20a: One side of the supporting sheet (first side) 11, 81: Substrate 11a, 81a: One side of the substrate (first side) 12, 82: Adhesive layer 12a, 82a: One side of the adhesive layer (first side) 13, 23: Protective film forming film for energy line hardening 13’: Protective film 13a, 23a: One side of the protective film forming film (first side) 13b, 23b: The other side of the protective film forming film (second side) 13a’: One side of the protective film ( 13b’: The other side of the protective film (2nd side) 15: Peeling film 16: Fixture adhesive layer 16a: One side of the fixture adhesive layer (1st side) 90: Wafer 90b: Inner side of the wafer 901: Wafer with protective film 130’: Protective film after cutting 130b’: The first side of the protective film 101, 102, 103, 104: Composite sheet for protective film formation; 151: First peel film; 152: Second peel film; 501: First laminated composite sheet; 502: Second laminated composite sheet; 503: Third laminated composite sheet; 601: First laminated film; 602: Second laminated film; 603: Third laminated film.

[Figure 1] is a schematic cross-sectional view illustrating an example of a protective film forming film according to an embodiment of the present invention. [Figure 2] is a schematic cross-sectional view illustrating an example of a composite sheet for forming a protective film according to an embodiment of the present invention. [Figure 3] is a schematic cross-sectional view illustrating another example of a composite sheet for forming a protective film according to an embodiment of the present invention. [Figure 4] is a schematic cross-sectional view illustrating yet another example of a composite sheet for forming a protective film according to an embodiment of the present invention. [Figure 5] is a schematic cross-sectional view illustrating yet another example of a composite sheet for forming a protective film according to an embodiment of the present invention. [Figure 6] is a schematic cross-sectional view illustrating an example of a method for manufacturing a wafer with a protective film according to an embodiment of the present invention. [Figure 7] is a cross-sectional view illustrating another example of a method for manufacturing a chip with a protective film, representing one embodiment of the present invention.

13: Protective film formation for energy line hardening 13a: One side of the protective film (side 1) 13b: The other side of the protective film (side 2) 151: First peeling membrane 152: Second peeling membrane

Claims (7)

A protective film forming film is an energy-line curable protective film forming film; the aforementioned protective film forming film contains an energy-line curable component (a), an acrylic resin (b) without energy-line curable groups, and a photopolymerization initiator (c); the content of the aforementioned energy-line curable component (a) relative to the total mass of the aforementioned protective film forming film is 12% to 31% by mass; the content of the aforementioned acrylic resin (b) without energy-line curable groups relative to the total mass of the aforementioned protective film forming film is 8% to 27% by mass; the content of the aforementioned photopolymerization initiator (c) relative to 100 parts by mass of the aforementioned energy-line curable component (a) is 0.1 parts by mass to 20 parts by mass; the weight (W ₃₎ of the protective film after the aforementioned protective film forming film is subjected to energy-line curing and heat-treated at 260°C for 10 minutes. The weight reduction rate ( _ΔW3 ) of the aforementioned protective film-forming film relative to the weight ( _W0 ) before energy line hardening is less than 3.0%; after energy line hardening of the aforementioned protective film-forming film, the gel content of components other than inorganic filler materials is more than 60%. The protective film forming film as described in claim 1, wherein the aforementioned photopolymerization initiator (c) contains 2-hydroxy-2-methyl-1-phenylpropane-1-one; or contains 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropoxy)benzyl)phenyl)-2-methylpropane-1-one; or contains 1-hydroxycyclohexyl-phenyl one and 2-(dimethylamino)-1-(4-mofolinphenyl)-2-benzyl-1-butanone. As described in claim 2, the protective film forming film comprises: a polymer (a1) having energy-curing groups and a weight-average molecular weight of 80,000 to 2,000,000, and a compound (a2) having energy-curing groups and a molecular weight of 100 to 80,000; and an acrylic resin (b) without energy-curing groups having a weight-average molecular weight (Mw) of 100. 00 to 2,000,000; the aforementioned photopolymerization initiator (c) contains only 2-hydroxy-2-methyl-1-phenylpropane-1-one; or contains 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropane)benzyl)phenyl)-2-methylpropane-1-one; or contains 1-hydroxycyclohexyl-phenyl one and 2-(dimethylamino)-1-(4-methyl-folin-phenyl)-2-benzyl-1-butanone. The protective film forming film as described in claim 1 or 2, wherein the gloss value (G2) of the protective film after energy line hardening and heat treatment at 260°C for 10 minutes is reduced by less than 30% relative to the gloss value (G1) of the protective film after energy line hardening. The protective film forming film as described in claim 1 or 2, wherein the aforementioned energy line hardening component (a) contains a polyfunctional (meth)acrylate oligomer. A composite sheet for forming a protective film comprises a support sheet and a protective film forming film disposed on one side of the support sheet; the protective film forming film is the protective film forming film as described in any one of claims 1 to 5. A method for manufacturing a wafer with a protective film is used to manufacture a wafer having a protective film disposed on the inner surface of the wafer; the method for manufacturing the wafer with a protective film includes the following steps: by attaching a protective film forming film as described in any one of claims 1 to 5 to the inner surface of the wafer to form the aforementioned protective film forming film and a first laminated film formed by laminating the wafer in the thickness direction of these layers; or by attaching a protective film forming film as described in any one of claims 1 to 5 to the inner surface of the wafer to form the protective film forming film and a first laminated film formed by laminating the wafer in the thickness direction of these layers; or by attaching a protective film forming film as described in any one of claims 1 to 5 to the inner surface of the wafer to form the protective film forming film. The step of attaching the protective film forming film as described in claim 6 to the inner surface of the composite sheet for forming the protective film, thereby fabricating a first laminated composite sheet composed of the support sheet, the protective film forming film, and the wafer sequentially laminated in the thickness direction of these layers; forming the protective film by energy line hardening the protective film forming film in the first laminated film or in the first laminated composite sheet, thereby fabricating the protective film and the wafer in the thickness direction of these layers. The process involves either fabricating a second laminated film formed by stacking layers in the thickness direction, or fabricating a second laminated composite film formed by sequentially stacking the aforementioned support sheet, protective film, and wafer in the thickness direction of these layers; with a dicing blade disposed on the protective film side of the second laminated film, the protective film is cut by dicing the wafer in the second laminated film to fabricate a third laminated film in which multiple wafers with protective films are fixed on the dicing blade. The steps include: a third laminated composite consisting of multiple wafers with protective films fixed on a support sheet by cutting the protective film in the second laminated composite; or picking up the wafers with protective films in the third laminated composite by peeling them off from the dicing sheet or by peeling them off from the support sheet.