PROTECTIVE FILM-FORMING FILM, PROTECTIVE FILM-FORMING COMPOSITE SHEET, AND PROTECTIVE FILM-COATED CHIP MANUFACTURING METHOD

Abstract

To provide a protective coat formation film with energy ray-curable properties, the protective coat formation film capable of preventing a bleedout by a reflow process for a protective coat formed by irradiating and curing the protective coat formation film with energy rays, a composite sheet for forming a protective coat having the protective coat formation film, and a manufacturing method of a chip having a protective coat that uses the protective coat formation film or the composite sheet for forming a protective coat.SOLUTION: A protective coat formation film 13 has energy ray-curable properties. The protective coat formation film 13 contains an energy ray-curable component (a). After curing the protective coat formation film by energy rays and applying a heat treatment thereto at 260°C for 10 minutes, a weight loss ratio is 3.0% or less. In the protective coat formation film after energy ray-curing, a gel fraction of components other than inorganic filler is 60% or more.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a protective film-forming film, a composite sheet for forming a protective film, and a method for producing a chip with a protective film. [Background technology]

[0002] Some wafers, such as semiconductor wafers and insulator wafers, have circuits formed on one surface (circuit surface) and also have protruding electrodes such as bumps on that surface (circuit surface). Such wafers are divided into chips, and the protruding electrodes are connected to connection pads on a circuit board, thereby mounting the chips on the circuit board. In such wafers and chips, the surface opposite to the circuit surface (back surface) may be protected with a protective film to prevent damage such as cracks.

[0003] To form such a protective film, a protective film-forming film for forming the protective film is attached to the back surface of the wafer. The protective film-forming film may be laminated on a support sheet for supporting it and used in the form of a composite sheet for forming a protective film, or may be used without being laminated on a support sheet. After laser marking on the protective film-forming film, the film may be cured with heat or energy rays as necessary to enhance the protective performance of the protective film-forming layer, and the semiconductor wafer may be divided into chips by dicing and picked up. Alternatively, the protective film formed by curing the protective film-forming film with heat or energy rays may be laser marked, and the semiconductor wafer may be divided into chips by dicing and picked up. The picked-up protective film-coated semiconductor chips are then flip-chip connected to connection pads on a circuit board such as a motherboard, and the circuit board is heated to melt the protruding electrodes on the protective film-coated chip (hereinafter referred to as a reflow process), strengthening the electrical connection between the protruding electrodes and the connection pads on the circuit board, and the chips are then mounted on the circuit board.

[0004] Among protective film-forming films, there are non-curable ones that do not have curing properties and function as a protective film as is. When a non-curable protective film-forming film is used, a curing step is not required, so chips with a protective film can be manufactured at low cost using a simplified method. On the other hand, when a curable protective film-forming film is used, the cured product serves as the protective film, which has the advantage of high wafer protection. While a thermosetting protective film-forming film that is cured by heating requires a relatively long heating time for curing, an energy ray-curable protective film-forming film that is cured by irradiation with energy rays has the advantage that energy ray irradiation for curing can be completed in a short time. Therefore, various developments of energy ray-curable protective film-forming films have been underway (see Patent Documents 1 to 3). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-031183 [Patent Document 2] International Publication No. 2017 / 188197 [Patent Document 3] International Publication No. 2019 / 082977 Summary of the Invention [Problem to be solved by the invention]

[0006] In a conventional method for manufacturing a semiconductor chip with a protective film using a protective film-forming film or a composite sheet for forming a protective film, a phenomenon in which low-molecular-weight compounds bleed out onto the surface of the protective film during the reflow process when the picked-up semiconductor chip with the protective film is mounted on a circuit board has been observed. Bleeding out onto the surface of the protective film can impair the design and can degrade the laser mark.

[0007] The present invention aims to provide an energy ray-curable protective film-forming film, in which the protective film formed by curing the protective film-forming film with energy rays is suppressed from bleeding out during a reflow process, a protective film-forming composite sheet including the protective film-forming film, and a method for manufacturing a chip with a protective film using the protective film-forming film or the protective film-forming composite sheet. [Means for solving the problem]

[0008] The present invention provides an energy ray-curable protective film-forming film, which contains an energy ray-curable component (a), and which has a weight loss rate of 3.0% or less after being energy ray-cured and heat-treated at 260°C for 10 minutes, and which has a gel fraction of components other than an inorganic filler of 60% or more after being energy ray-cured.

[0009] In the protective film-forming film of the present invention, it is preferable that the reduction rate of the gloss value (G2) of the protective film after curing the protective film with energy rays and heat-treating the protective film at 260°C for 10 minutes relative to the gloss value (G1) of the protective film after curing the protective film with energy rays is 30% or less.

[0010] In the protective film-forming film of the present invention, the energy ray-curable component (a) preferably contains a polyfunctional urethane (meth)acrylate oligomer.

[0011] The present invention also provides a composite sheet for forming a protective film, comprising a support sheet and a protective film-forming film provided on one side of the support sheet, wherein the protective film-forming film is the protective film-forming film of the present invention described above.

[0012] The present invention also provides a method for manufacturing a chip with a protective film, the chip including a chip and a protective film provided on the back surface of the chip, the method for manufacturing the chip with a protective film comprising: a step of attaching the protective film-forming film of the present invention to the back surface of a wafer to produce a first laminated film in which the protective film-forming film and the wafer are laminated in their thickness direction, or a step of attaching the protective film-forming film in the composite sheet for forming a protective film of the present invention to the back surface of a wafer to produce a first laminated composite sheet in which the support sheet, the protective film-forming film, and the wafer are laminated in this order in their thickness direction, and a step of curing the protective film-forming film in the first laminated film or in the first laminated composite sheet with energy rays to form the protective film, to produce a second laminated film in which the protective film and the wafer are laminated in their thickness direction, or a step of producing a second laminated composite sheet in which a wafer, a protective film, and a wafer are laminated in this order in the thickness direction; a step of dividing the wafer in the second laminated film and cutting the protective film with a dicing sheet provided on the protective film side of the second laminated film to produce a third laminated film in which a plurality of the protective film-coated chips are fixed on the dicing sheet, or a step of dividing the wafer in the second laminated composite sheet and cutting the protective film to produce a third laminated composite sheet in which a plurality of the protective film-coated chips are fixed on the support sheet; and a step of picking up the protective film-coated chips in the third laminated film by either separating the protective film-coated chips in the third laminated film from the dicing sheet or separating the protective film-coated chips in the third laminated composite sheet by separating the protective film-coated chips in the third laminated film from the dicing sheet. [Effects of the Invention]

[0013] According to the present invention, there are provided an energy ray-curable protective film-forming film, in which the protective film formed by curing the protective film-forming film with energy rays is suppressed from bleeding out during a reflow process, a protective film-forming composite sheet including the protective film-forming film, and a method for manufacturing a chip with a protective film using the protective film-forming film or the protective film-forming composite sheet. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a cross-sectional view schematically illustrating an example of a protective film-forming film according to an embodiment of the present invention. [Figure 2] 1 is a cross-sectional view schematically illustrating an example of a composite sheet for forming a protective film according to an embodiment of the present invention. [Figure 3] FIG. 3 is a cross-sectional view schematically showing another example of a composite sheet for forming a protective film according to one embodiment of the present invention. [Figure 4] FIG. 10 is a cross-sectional view schematically showing yet another example of a composite sheet for forming a protective film according to one embodiment of the present invention. [Figure 5] FIG. 10 is a cross-sectional view schematically showing yet another example of a composite sheet for forming a protective film according to one embodiment of the present invention. [Figure 6] 1A to 1C are cross-sectional views for schematically explaining an example of a method for manufacturing a chip with a protective film according to an embodiment of the present invention. [Figure 7] 10A to 10C are cross-sectional views for schematically explaining another example of a method for manufacturing a chip with a protective film according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0015] ◇Protective film forming film A protective film-forming film according to one embodiment of the present invention is an energy ray-curable protective film-forming film, which contains an energy ray-curable component (a), and after the protective film is energy ray-cured and heat-treated at 260°C for 10 minutes, the weight loss rate is 3.0% or less, and after the protective film is energy ray-cured, the gel fraction of components other than the inorganic filler is 60% or more. The protective film-forming film of this embodiment is a film used to provide a protective film on a chip to protect the chip.

[0016] By using the protective film-forming film of this embodiment or a composite sheet for forming a protective film comprising the same, a chip with a protective film can be manufactured that comprises a chip and a protective film provided on the back surface of the chip. The chip with the protective film can be manufactured, for example, by attaching a protective film-forming film to the back surface of a wafer, forming a protective film by hardening the protective film-forming film, dividing the wafer into chips, and cutting the protective film along the outer periphery of the chip.

[0017] In this specification, the term "wafer" refers to a semiconductor wafer made of an elemental semiconductor such as silicon, germanium, or selenium, or a compound semiconductor such as GaAs, GaP, InP, CdTe, ZnSe, or SiC; or an insulating wafer made of an insulating material such as sapphire, glass, lithium niobate, or lithium tantalate. A circuit is formed on one surface of each of these wafers, and in this specification, the surface of the wafer on which the circuit is formed is referred to as the "circuit side," and the surface of the wafer opposite the circuit side is referred to as the "back side." The wafer is divided into chips by dicing or other means. In this specification, as with the wafer, the surface of the chip on which the circuit is formed is referred to as the "circuit side," and the surface of the chip opposite the circuit side is referred to as the "back side." Both the circuit surface of the wafer and the circuit surface of the chip are provided with protruding electrodes such as bumps, pillars, etc. The protruding electrodes are preferably made of solder.

[0018] Furthermore, by using the chip with the protective film, a substrate device can be manufactured. In this specification, the term "substrate device" refers to a device in which a chip with a protective film is flip-chip connected to connection pads on a circuit board at protruding electrodes on the circuit surface of the chip. For example, if a semiconductor wafer is used as the wafer, the substrate device may be a semiconductor device.

[0019] The protective film-forming film of the present embodiment is energy ray-curable and may or may not be thermosetting. When the protective film-forming film of the present embodiment has both energy ray-curable and thermosetting properties, the contribution of energy ray curing of the protective film-forming film to the formation of the protective film is greater than the contribution of thermosetting.

[0020] As used herein, "energy rays" refers to electromagnetic waves or charged particle beams that have an energy quantum. Examples of energy rays include ultraviolet rays, radioactive rays, and electron beams. Ultraviolet rays can be irradiated using, for example, a high-pressure mercury lamp, a fusion lamp, a xenon lamp, a black light, or an LED lamp as an ultraviolet light source. Electron beams can be irradiated using those generated by an electron beam accelerator or the like. In this specification, "energy ray curable" means a property of being cured by irradiation with energy rays, and "non-energy ray curable" means a property of not being cured even when irradiated with energy rays. Moreover, "non-curable" means a property that does not cure by any means such as heating or irradiation with energy rays.

[0021] The curing conditions when the protective film-forming film is cured with energy rays to form a protective film are not particularly limited as long as the degree of curing is such that the protective film can fully perform its function, and may be selected appropriately depending on the type of protective film-forming film. For example, the irradiance of the energy ray when the energy ray curable protective film forming film is cured with the energy ray is 60 to 320 mW / cm2 The amount of energy rays during the curing is preferably 100 to 1000 mJ / cm. 2 It is preferable that:

[0022] The protective film-forming film may, for example, contain an energy ray-curable component (a) and an acrylic resin (b) having no energy ray-curable group. The components contained in the protective film-forming film will be described in detail later.

[0023] The protective film-forming film preferably has a weight loss rate ΔW1 after heat treatment at 130° C. for 2 hours of 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. and 2 hours are general conditions for heat curing when the protective film-forming film is thermosetting. When the weight loss rate ΔW1 is equal to or less than the upper limit, bleeding out is suppressed when the protective film-forming film is heat-treated. For example, using a TG / DTA simultaneous measurement 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 loss rate (ΔW1) (wt%) can be calculated from the weight (W0) of the protective film-forming film before heating and the weight (W1) of the protective film-forming film after heating using the following formula (1). ΔW1=(W0-W1) / W0×100 (1)

[0024] The protective film-forming film preferably has a weight loss rate ΔW2 after energy ray curing of 0.30% or less, more preferably 0.25% or less, and even more preferably 0.20% or less. Here, the conditions for energy ray curing are not limited as long as the conditions are such that the protective film-forming film is sufficiently energy ray cured.

[0025] Using a UV irradiation device, the protective film is exposed to an illuminance of 200 mW / cm2 , light intensity 300mJ / cm 2 The protective film-forming film is irradiated twice with ultraviolet light having a wavelength of 365 nm under the conditions described above. The weight loss rate (ΔW2) (wt%) can be calculated from the weight (W0) of the protective film-forming film before ultraviolet light irradiation and the weight (W2) of the protective film-forming film after heating using the following formula (2). ΔW2=(W0-W2) / W0×100 (2)

[0026] The protective film-forming film has a weight loss rate ΔW3 of 3.0% or less after being energy ray cured and heat-treated at 260° C. for 10 minutes. When the weight loss rate ΔW3 is 3.0% or less, bleeding out during the reflow process is suppressed in the protective film formed by curing the protective film-forming film with energy rays. If the weight loss rate ΔW3 after curing the protective film-forming film with energy rays and heat-treating it at 260°C for 10 minutes is small, it is thought that there will be less low-molecular-weight substances bleeding out onto the protective film surface during the reflow process when mounting the protective film-equipped semiconductor chip on a circuit board.

[0027] Here, the conditions for energy ray curing are not limited as long as the protective film-forming film is sufficiently cured by the energy ray. For example, the conditions are: illuminance 200 mW / cm 2 , light intensity 300mJ / cm 2 It is sufficient to irradiate the film with ultraviolet light having a wavelength of 365 nm twice under the conditions described above. The energy ray curing treatment can be carried out using, for example, a UV irradiation device RAD2000 manufactured by Lintec Corporation. The protective film after UV irradiation is heated from 25°C to 260°C at a heating rate of 10°C / min using, for example, a TG / DTA simultaneous measurement device, and then heated at 260°C for 10 minutes. The weight loss rate (ΔW3) (wt%) can be calculated from the weight (W0) of the protective film-forming film before UV irradiation and the weight (W3) of the protective film after heating using the following formula (3): ΔW3=(W0-W3) / W0×100 (3)

[0028] The weight loss rate ΔW3 is preferably 2.8% or less, more preferably 2.6% or less, and even more preferably 2.4% or less.

[0029] The protective film-forming film has a gel fraction of 60% or more of components other than the inorganic filler after being cured with energy rays. When the gel fraction is 60% or more, bleeding out during a reflow process is suppressed in the protective film formed by curing the protective film-forming film with energy rays. It is thought that if the gel fraction of components other than the inorganic filler is large, there will be less low-molecular-weight material bleeding out onto the protective film surface during the reflow process when mounting a semiconductor chip with a protective film on a circuit board. Here, the gel fraction of components other than the inorganic filler refers to the degree to which components other than the inorganic filler have gelled in the protective film after the protective film-forming film has been cured with energy rays. In the protective film-forming film, the inorganic filler is excluded because it does not contribute to the gelation of the resin component due to energy ray curing.

[0030] Next, a method for measuring the gel fraction of components other than the inorganic filler will be described. The protective film is applied at an illumination intensity of 200mW / cm 2 , light intensity 300mJ / cm 2 Under the conditions, the protective film is irradiated twice with ultraviolet light at a wavelength of 365 nm. After ultraviolet irradiation, the protective film is wrapped in, for example, a nylon mesh sheet (mesh size 200) and stapled to form a test piece. The mass M1 of the test piece, the mass M2 of the nylon mesh sheet, and the mass M3 of the staples are weighed using a precision balance. In addition, the mass M4 of the inorganic filler (d) in the test piece of the protective film-forming film is determined in advance. The mass M4 of the inorganic filler (d) can be calculated from the amount blended when the protective film-forming film is produced. The test piece is then immersed in ethyl acetate at 25°C for 48 hours, after which the insoluble portion of the protective film after UV irradiation, the nylon mesh sheet, and the staples are removed and dried. The mass M5 of the test piece after immersion and drying is then weighed using a precision balance. The gel fraction of the components other than the inorganic filler can then be calculated using the following formula (4): ΔG=(M5-M2-M3-M4) / (M1-M2-M3-M4)×100 (4)

[0031] Here, (M1-M2-M3-M4) is the mass of the components other than the inorganic filler in the protective film after energy ray curing, and (M5-M2-M3-M4) is the mass of the components insoluble in ethyl acetate other than the inorganic filler in the protective film after energy ray curing.

[0032] The rate of decrease in the gloss value (G2) of the protective film after energy ray-curing the protective film-forming film and heat-treating it at 260°C for 10 minutes relative to the gloss value (G1) of the protective film after energy ray-curing the protective film-forming film is preferably 30% or less, more preferably 28% or less, and even more preferably 26% or less. When the rate of decrease is equal to or less than the upper limit, bleeding out of the surface of the protective film formed by curing the protective film-forming film with energy rays is suppressed in the reflow process when mounting the protective film on a circuit board.

[0033] The gloss value (G1) and the gloss value (G2) are both measured in a state where a protective film formed by curing a protective film-forming film with energy rays is laminated on a wafer to be protected. The gloss value of the protective film is measured from the protective film side under the condition of an incident angle of 60°.

[0034] More specifically, the protective film-forming film in the first laminate film is cured with energy rays to form the protective film, thereby producing a second laminate film in which the protective film and the wafer are laminated in their thickness direction. The gloss value (G1) of the protective film is measured from the protective film side of the second laminate film using a glossmeter at an incident angle of 60°. Thereafter, the second laminate film is heated at 260°C for 10 minutes, and the gloss value (G2) of the protective film after heating can be measured under the same conditions as the gloss value (G1) before heating. Furthermore, the protective film-forming film in the first laminate composite sheet is cured with energy rays to form the protective film, thereby producing a second laminate composite sheet configured by stacking the support sheet, protective film, and wafer in this order in the thickness direction. The support sheet is peeled off from the second laminate composite sheet to prepare a test piece, and the gloss value (G1) of the protective film is measured from the protective film side using a gloss meter at an incident angle of 60°. Thereafter, the test piece is heated at 260°C for 10 minutes, and the gloss value (G2) of the protective film after heating can be measured under the same conditions as the measurement of the gloss value (G1) before heating.

[0035] The reduction rate (%) of the gloss value of the protective film after heat treatment at 260° C. for 10 minutes can be calculated using the following formula (5). Gloss value decrease rate (%) = (G1 - G2) / G1 × 100 (5)

[0036] The protective film-forming film preferably satisfies the following condition for storage modulus E'. That is, a test piece of a 200 μm thick protective film-forming film (sometimes simply referred to as a "protective film-forming film test piece" in this specification), which is a laminate of a plurality of protective film-forming films, is held at two points spaced 20 mm apart, and the storage modulus E' of the protective film-forming film test piece is measured between the two points under measurement conditions of a tensile mode with a frequency of 11 Hz and a temperature rise rate of 3° C. / min in a temperature range of -10° C. to 140° C. The storage modulus E' of the protective film-forming film test piece at 70° C. 70The storage modulus E' is preferably 30 MPa or less, more preferably 10 MPa or less, and may be, for example, 5 MPa or less. 70 When the thickness is equal to or less than the upper limit, the protective film-forming film can be more easily attached to the object (wafer). The storage modulus E' 70 The lower limit of the storage modulus E' is not particularly limited. 70 A protective film-forming film having a compressive strength of 0.5 MPa or more can be produced more easily and forms a protective film with better properties.

[0037] The length of the protective film-forming film test piece in the tensile direction in the tensile mode is not particularly limited as long as it does not impair the measurement accuracy of the storage modulus E', but is preferably 30 mm or more. When measuring the storage modulus E' of the protective film-forming film test piece, it is preferable to raise the temperature of the test piece at a constant rate. When measuring the storage modulus E' of the protective film-forming film specimen, the amplitude is preferably 5 μm.

[0038] The protective film, which is the energy ray-cured product of the protective film-forming film, preferably satisfies the following condition for storage modulus E'. That is, a laminate of a plurality of protective film-forming films, the thickness of which is 50 μm, is exposed to an illuminance of 200 mW / cm from both sides. 2 , light intensity 300mJ / cm 2 The protective film-forming film was cured by irradiating it twice with ultraviolet light having a wavelength of 365 nm under the conditions above to obtain a protective film test piece (sometimes simply referred to as a "protective film test piece" in this specification). The protective film test piece was held at two points spaced 20 mm apart, and the storage modulus E' of the protective film test piece was measured between the two points under measurement conditions of a tensile mode with a frequency of 11 Hz and a temperature rise rate of 3°C / min in a temperature range from 0°C to 300°C. The storage modulus E' of the protective film test piece at 130°C was 130The storage modulus E' is preferably 5 MPa or more, more preferably 8 MPa or more, and even more preferably 10 MPa or more. 130 When the value is equal to or greater than the lower limit, the protective effect of the protective film on the object (wafer) to be attached is further improved. The storage modulus E' 130 There is no particular upper limit to the storage modulus E'. 130 A protective film having a modulus of 3000 MPa or less is easier to manufacture and has better properties.

[0039] The length of the protective film test piece in the tensile direction in the tensile mode is not particularly limited as long as it does not impair the measurement accuracy of the storage modulus E', but is preferably 30 mm or more. When measuring the storage modulus E' of the protective film test piece, it is preferable to raise the temperature of the test piece at a constant rate. When measuring the storage modulus E' of the protective film test piece, the amplitude is preferably 5 μm.

[0040] The storage modulus E' of the protective film-forming film test piece and the protective film test piece (in other words, the storage modulus E' of the protective film-forming film and the protective film) can be reduced, for example, by increasing the content of low-molecular-weight polymer components, such as the energy ray-curable component (a) described below, in the protective film-forming film. Furthermore, the storage modulus E' of the protective film-forming film test piece can also be reduced by increasing the content of the inorganic filler (d) described below in the protective film-forming film. On the other hand, the storage modulus E' of the protective film test piece can be increased by increasing the content of the energy ray-curable component (a) described below in the protective film-forming film. Also, the storage modulus E' of the protective film test piece can be increased by decreasing the content of the inorganic filler (d) described below in the protective film-forming film.

[0041] The protective film-forming film may be composed of one layer (single layer) or two or more layers. When the protective film-forming film is composed of multiple layers, these multiple layers may be the same or different from each other, and the combination of these multiple layers is not particularly limited.

[0042] In this specification, not only in the case of a protective film-forming film, "multiple layers may be the same or different from each other" means "all layers may be the same, all layers may be different, or only some layers may be the same," and further, "multiple layers are different from each other" means "at least one of the constituent materials and thicknesses of each layer is different from each other."

[0043] The thickness of the protective film-forming film is preferably 1 to 100 μm, more preferably 3 to 80 μm, and particularly preferably 5 to 60 μm. When the thickness of the protective film-forming film is equal to or greater than the lower limit, a protective film with higher protective ability can be formed. When the thickness of the protective film-forming film is equal to or less than the upper limit, the thickness of the protective film-coated chip can be prevented from becoming excessive. Here, "thickness of the protective film-forming film" means the thickness of the entire protective film-forming film, and for example, the thickness of a protective film-forming film consisting of multiple layers means the total thickness of all layers that make up the protective film-forming film.

[0044] <<Composition for forming protective film>> The protective film-forming film can be formed using an energy ray-curable protective film-forming composition (sometimes simply referred to as "protective film-forming composition" in this specification) containing its constituent materials. For example, the protective film-forming film can be formed by applying the protective film-forming composition to the surface to be formed and drying it as necessary. The ratio of the contents of the components that do not vaporize at room temperature in the protective film-forming composition is usually the same as the ratio of the contents of the components in the protective film-forming film. In this specification, "room temperature" means a temperature that is not particularly cooled or heated, i.e., an ordinary temperature, and examples thereof include a temperature of 18 to 28°C.

[0045] The protective film-forming composition may be applied by a known method, such as a method using various coaters such as an air knife coater, blade coater, bar coater, gravure coater, roll coater, roll knife coater, curtain coater, die coater, knife coater, screen coater, Mayer bar coater, or kiss coater.

[0046] The drying conditions for the protective film-forming composition are not particularly limited. However, when the protective film-forming composition contains a solvent, which will be described later, it is preferable to heat-dry it. The protective film-forming composition containing the solvent is preferably heat-dried, for example, at 70 to 130°C for 10 seconds to 5 minutes. However, the protective film-forming composition having thermosetting properties is preferably heat-dried so as not to thermally cure the composition itself or the thermosetting protective film-forming film formed from this composition.

[0047] <Energy ray-curable protective film-forming composition (IV)> A preferred example of a composition for forming a protective film is an energy ray-curable composition for forming a protective film (IV) (sometimes simply referred to as "composition (IV)" in this specification) containing the energy ray-curable component (a), the acrylic resin (b) having no energy ray-curable group, and the inorganic filler (d).

[0048] [Energy ray curable component (a)] The energy ray-curable component (a) is a component that is cured by irradiation with energy rays, and imparts film-forming properties, flexibility, etc. to the protective film-forming film, and is also a component for forming a hard protective film after curing. By containing the energy ray-curable component (a), the protective film-forming film forms a protective film with good properties. In the protective film-forming film, the energy ray-curable component (a) is preferably uncured and has adhesive properties, and more preferably uncured and has adhesive properties.

[0049] Examples of the energy ray-curable component (a) include a polymer (a1) having an energy ray-curable group and a weight-average molecular weight of 80,000 to 2,000,000, and a compound (a2) having an energy ray-curable group and a molecular weight of 100 to 80,000. The polymer (a1) may be at least partially crosslinked with a crosslinking agent, or may not be crosslinked.

[0050] (Polymer (a1) having an energy ray-curable group and a weight-average molecular weight of 80,000 to 2,000,000) Examples of the polymer (a1) having an energy ray-curable group and a weight average molecular weight of 80,000 to 2,000,000 include an acrylic resin (a1-1) obtained by reacting an acrylic polymer (a11) having a functional group capable of reacting with a group possessed by another compound with an energy ray-curable compound (a12) having a group reactive with the functional group and an energy ray-curable group such as an energy ray-curable double bond.

[0051] Examples of the functional group capable of reacting with a group possessed by another compound include a hydroxyl group, a carboxy group, an amino group, a substituted amino group (a group having a structure in which one or two hydrogen atoms of an amino group are substituted with a group other than a hydrogen atom), an epoxy group, etc. However, from the viewpoint of preventing corrosion of circuits of a wafer, a chip, etc., it is preferable that the functional group be a group other than a carboxy group. Among these, the functional group is preferably a hydroxyl group.

[0052] Acrylic polymers having functional groups (a11) The acrylic polymer (a11) having a functional group may be, for example, a polymer obtained by copolymerizing an acrylic monomer having the functional group with an acrylic monomer not having the functional group, and may also be a polymer obtained by copolymerizing, in addition to these monomers, a monomer other than the acrylic monomer (a non-acrylic monomer). The acrylic polymer (a11) may be a random copolymer or a block copolymer, and known methods can be used for the polymerization method.

[0053] Examples of the acrylic monomer having a functional group include a hydroxyl group-containing monomer, a carboxy group-containing monomer, an amino group-containing monomer, a substituted amino group-containing monomer, and an epoxy group-containing monomer.

[0054] Examples of the hydroxyl group-containing monomer include hydroxyalkyl (meth)acrylates such as 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; and non-(meth)acrylic unsaturated alcohols (unsaturated alcohols not having a (meth)acryloyl skeleton) such as vinyl alcohol and allyl alcohol.

[0055] Examples of the carboxy group-containing monomer include ethylenically unsaturated monocarboxylic acids (monocarboxylic acids having an ethylenically unsaturated bond) such as (meth)acrylic acid and crotonic acid; ethylenically unsaturated dicarboxylic acids (dicarboxylic acids having an ethylenically unsaturated bond) such as fumaric acid, itaconic acid, maleic acid and citraconic acid; anhydrides of the ethylenically unsaturated dicarboxylic acids; and (meth)acrylic acid carboxyalkyl esters such as 2-carboxyethyl methacrylate.

[0056] The acrylic monomer having a functional group is preferably a hydroxyl group-containing monomer.

[0057] The acrylic monomer having a functional group that constitutes the acrylic polymer (a11) may be of only one type or of two or more types, and when two or more types are used, the combination and ratio thereof can be selected arbitrarily.

[0058] Examples of the acrylic monomer not having a functional group include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, and isopropyl (meth)acrylate. Examples of alkyl (meth)acrylate esters include those in which the alkyl group constituting the alkyl ester has a chain structure having 1 to 18 carbon atoms, such as sononyl, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauryl (meth)acrylate), tridecyl (meth)acrylate, tetradecyl (meth)acrylate (myristyl (meth)acrylate), pentadecyl (meth)acrylate, hexadecyl (meth)acrylate (palmityl (meth)acrylate), heptadecyl (meth)acrylate, and octadecyl (meth)acrylate (stearyl (meth)acrylate).

[0059] Examples of the acrylic monomer not having a functional group include alkoxyalkyl group-containing (meth)acrylic acid esters such as methoxymethyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxymethyl (meth)acrylate, and ethoxyethyl (meth)acrylate; (meth)acrylic acid esters having an aromatic group, including (meth)acrylic acid aryl esters such as phenyl (meth)acrylate; non-crosslinkable (meth)acrylamide and derivatives thereof; and non-crosslinkable tertiary amino group-containing (meth)acrylic acid esters such as N,N-dimethylaminoethyl (meth)acrylate and N,N-dimethylaminopropyl (meth)acrylate.

[0060] The acrylic monomer not having a functional group constituting the acrylic polymer (a11) may be of only one type or of two or more types, and when two or more types are used, the combination and ratio thereof can be selected arbitrarily.

[0061] Examples of the non-acrylic monomer include olefins such as ethylene and norbornene; vinyl acetate; and styrene. The non-acrylic monomer constituting the acrylic polymer (a11) may be of only one kind or of two or more kinds, and when two or more kinds are used, the combination and ratio thereof can be selected arbitrarily.

[0062] In the acrylic polymer (a11), the proportion (content) of the structural units derived from the acrylic monomer having the functional group relative to the total amount of structural units constituting the acrylic polymer (a11) is preferably 0.1 to 50 mass%, more preferably 1 to 40 mass%, and particularly preferably 3 to 30 mass%. When the proportion is within this range, the content of the energy ray-curable group in the acrylic resin (a1-1) obtained by copolymerization of the acrylic polymer (a11) and the energy ray-curable compound (a12) can adjust the degree of curing of the protective film within a preferred range.

[0063] The acrylic polymer (a11) constituting the acrylic resin (a1-1) may be one kind or two or more kinds, and when two or more kinds are used, the combination and ratio thereof can be selected arbitrarily.

[0064] The content of the acrylic resin (a1-1) in the protective film-forming film relative to the total mass of the protective film-forming film is preferably 1 to 70 mass%, more preferably 5 to 60 mass%, and particularly preferably 10 to 50 mass%.

[0065] Energy ray curable compounds (a12) The energy ray-curable compound (a12) preferably has one or more groups selected from the group consisting of an isocyanate group, an epoxy group, and a carboxy group as a group reactive with the functional group of the acrylic polymer (a11), and more preferably has an isocyanate group as the group. For example, when the energy ray-curable compound (a12) has an isocyanate group as the group, the isocyanate group easily reacts with the hydroxyl group of the acrylic polymer (a11) having the hydroxyl group as the functional group.

[0066] The number of energy ray-curable groups that the energy ray-curable compound (a12) has in one molecule is not particularly limited and can be appropriately selected in consideration of, for example, the physical properties required for the target protective film, such as the shrinkage rate. For example, the energy ray-curable compound (a12) preferably has 1 to 5, and more preferably 1 to 3, energy ray-curable groups in one molecule.

[0067] Examples of the energy ray-curable compound (a12) include 2-methacryloyloxyethyl isocyanate, meta-isopropenyl-α,α-dimethylbenzyl isocyanate, methacryloyl isocyanate, allyl isocyanate, and 1,1-(bisacryloyloxymethyl)ethyl isocyanate; an acryloyl monoisocyanate compound obtained by reacting a diisocyanate compound or a polyisocyanate compound with hydroxyethyl (meth)acrylate; Examples thereof include an acryloyl monoisocyanate compound obtained by reacting a diisocyanate compound or polyisocyanate compound with a polyol compound and hydroxyethyl (meth)acrylate. Among these, the energy ray-curable compound (a12) is preferably 2-methacryloyloxyethyl isocyanate.

[0068] The energy ray-curable compound (a12) constituting the acrylic resin (a1-1) may be one type or two or more types, and when two or more types are used, the combination and ratio thereof can be selected arbitrarily.

[0069] In the acrylic resin (a1-1), the ratio of the content of the energy ray-curable group derived from the energy ray-curable compound (a12) to the content of the functional group derived from the acrylic polymer (a11) is preferably 20 to 120 mol%, more preferably 35 to 100 mol%, and particularly preferably 50 to 100 mol%. When the content ratio is within such a range, the adhesive strength of the cured product of the protective film-forming film is further increased. Note that when the energy ray-curable compound (a12) is a monofunctional compound (having one such group per molecule), the upper limit of the content ratio is 100 mol%, but when the energy ray-curable compound (a12) is a polyfunctional compound (having two or more such groups per molecule), the upper limit of the content ratio may exceed 100 mol%.

[0070] The weight average molecular weight (Mw) of the polymer (a1) is preferably 100,000 to 2,000,000, and more preferably 300,000 to 1,500,000. Here, the "weight average molecular weight" is as explained above.

[0071] The polymer (a1) contained in the composition (IV) and the protective film-forming film may be one type or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0072] (Compound (a2) having an energy ray-curable group and a molecular weight of 100 to 80,000) The energy ray-curable group in the compound (a2) having an energy ray-curable group and a molecular weight of 100 to 80,000 includes a group containing an energy ray-curable double bond, and preferred examples thereof include a (meth)acryloyl group and a vinyl group.

[0073] The compound (a2) is not particularly limited as long as it satisfies the above conditions, and examples thereof include a low-molecular-weight compound having an energy ray-curable group, an epoxy resin having an energy ray-curable group, and a phenolic resin having an energy ray-curable group.

[0074] Among the compounds (a2), examples of the low molecular weight compound having an energy ray-curable group include polyfunctional monomers or oligomers, and acrylate compounds having a (meth)acryloyl group are preferred.

[0075] Examples of the acrylate compound include polyfunctional monomers or oligomers, and polyfunctional acrylate compounds having two or more (meth)acryloyl groups in one molecule are preferred. Examples of the polyfunctional acrylate compound include 2-hydroxy-3-(meth)acryloyloxypropyl 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)acryloyloxyethoxy)phenyl]fluorene, 2,2-bis[4-((meth)acryloxypolypropoxy)phenyl]propane, tricyclodecane dimethanol di(meth)acrylate (also known as tricyclodecane dimethylol di(meth)acrylate), 1,10-decane diol di(meth)acrylate, 1, Bifunctional (meth)acrylates ((meth)acrylates having two (meth)acryloyl groups in one molecule) such as 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, and 2-hydroxy-1,3-di(meth)acryloxypropane; Polyfunctional (meth)acrylates ((meth)acrylates having three or more (meth)acryloyl groups in one molecule), such as tris(2-(meth)acryloxyethyl)isocyanurate, ε-caprolactone-modified tris-(2-(meth)acryloxyethyl)isocyanurate, ethoxylated glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol poly(meth)acrylate, and dipentaerythritol hexa(meth)acrylate; Examples include polyfunctional (meth)acrylate oligomers ((meth)acrylate oligomers having two or more (meth)acryloyl groups in one molecule), such as polyfunctional urethane (meth)acrylate oligomers.

[0076] Among the compounds (a2), examples of the epoxy resin having an energy ray-curable group and the phenolic resin having an energy ray-curable group that can be used include those described in paragraph 0043 of JP 2013-194102 A. Although such resins also fall under the category of resins constituting the thermosetting component described below, they are treated as the compound (a2) in the composition (IV).

[0077] The weight average molecular weight of the compound (a2) is preferably 100 to 30,000, and more preferably 300 to 10,000.

[0078] The compound (a2) contained in the composition (IV) and the protective film-forming film may be one type or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0079] The protective film-forming film preferably contains the compound (a2) as the energy ray-curable component (a), more preferably a polyfunctional acrylate compound having two or more (meth)acryloyl groups in one molecule, and even more preferably a polyfunctional urethane (meth)acrylate oligomer. The cured product (protective film) of the protective film-forming film containing such energy ray-curable component (a) by energy ray irradiation has good protective ability and flexibility, and has particularly excellent properties.

[0080] When the composition (IV) and the protective film-forming film contain the energy ray-curable component (a), the content of the energy ray-curable component (a) in the composition (IV) and the protective film-forming film is preferably 100 to 310 parts by mass, more preferably 130 to 280 parts by mass, relative to 100 parts by mass of the acrylic resin (b), and may be, for example, 130 to 200 parts by mass or 210 to 280 parts by mass.

[0081] In composition (IV), the content ratio of the energy ray-curable component (a) relative to the total content of all components other than the solvent (i.e., the content ratio of the energy ray-curable component (a) in the protective film relative to the total mass of the protective film) is preferably 12 to 31 mass%, more preferably 14 to 28 mass%, and even more preferably 16 to 25 mass%. When the content ratio of the energy ray-curable component (a) (i.e., the content ratio of the energy ray-curable component (a)) is not less than the lower limit, the energy ray curability of the protective film-forming film becomes better, and in the protective film formed by curing the protective film-forming film with energy rays, bleeding out during the reflow process is more suppressed. When the content ratio of the energy ray-curable component (a) (i.e., the content ratio of the energy ray-curable component (a)) is not more than the upper limit, it is easy to prepare a desired protective film-forming film.

[0082] [Acrylic resin (b) not having an energy ray-curable group] The protective film-forming film preferably contains an acrylic resin (b) that does not have an energy ray-curable group (sometimes simply referred to as "acrylic resin (b)" in this specification).

[0083] The acrylic resin (b) is a component that imparts film-forming properties to the protective film-forming film.

[0084] The acrylic resin (b) may be a known one, for example, a homopolymer of one type of acrylic monomer, a copolymer of two or more types of acrylic monomers, or a copolymer of one or more types of acrylic monomers and one or more types of monomers other than the acrylic monomers (non-acrylic monomers).

[0085] The acrylic resin (b) may be at least partially crosslinked with a crosslinking agent, or may not be crosslinked.

[0086] Examples of the acrylic monomer constituting the acrylic resin (b) include (meth)acrylic acid alkyl esters, (meth)acrylic acid esters having no functional group but a cyclic skeleton, glycidyl group-containing (meth)acrylic acid esters, hydroxyl group-containing (meth)acrylic acid esters, substituted amino group-containing (meth)acrylic acid esters, carboxyl group-containing (meth)acrylic acid esters, and amino group-containing (meth)acrylic acid esters; (meth)acrylamide; and (meth)acrylamide derivatives such as 4-(meth)acryloylmorpholine. Here, the term "substituted amino group" refers to a group having a structure in which one or two hydrogen atoms of an amino group are substituted with a group other than a hydrogen atom. Here, the term "functional group" refers to a group (reactive functional group) that can react with other groups, such as a glycidyl group, a hydroxyl group, a substituted amino group, a carboxyl group, or an amino group.

[0087] In this specification, the term "(meth)acrylic acid" is a concept that encompasses both "acrylic acid" and "methacrylic acid." The same applies to terms similar to (meth)acrylic acid; for example, "(meth)acrylate" is a concept that encompasses both "acrylate" and "methacrylate," and "(meth)acryloyl group" is a concept that encompasses both "acryloyl group" and "methacryloyl group."

[0088] In this specification, when a structure in which one or more hydrogen atoms in a particular compound are substituted with a group other than a hydrogen atom is assumed, the compound having such a substituted structure is referred to as a "derivative" of the particular compound. In this specification, the term "group" includes not only an atomic group formed by bonding multiple atoms but also a single atom.

[0089] Examples of the (meth)acrylic acid alkyl esters not having a functional group and a cyclic skeleton include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, and (meth)acrylate alkyl esters in which the alkyl group constituting the alkyl ester has a chain structure and has 1 to 18 carbon atoms, such as isononyl acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauryl (meth)acrylate), tridecyl (meth)acrylate, tetradecyl (meth)acrylate (myristyl (meth)acrylate), pentadecyl (meth)acrylate, hexadecyl (meth)acrylate (palmityl (meth)acrylate), heptadecyl (meth)acrylate, and octadecyl (meth)acrylate (stearyl (meth)acrylate).

[0090] Examples of the (meth)acrylic acid ester having no functional group and a cyclic skeleton include (meth)acrylic acid cycloalkyl esters such as isobornyl (meth)acrylate and dicyclopentanyl (meth)acrylate; (Meth)acrylic acid aralkyl esters such as benzyl (meth)acrylate; (Meth)acrylic acid cycloalkenyl esters such as (meth)acrylic acid dicyclopentenyl ester; (Meth)acrylic acid cycloalkenyloxyalkyl esters such as (meth)acrylic acid dicyclopentenyloxyethyl ester are included.

[0091] Examples of the glycidyl group-containing (meth)acrylic acid ester include glycidyl (meth)acrylate. Examples of the hydroxyl group-containing (meth)acrylic acid ester include those having a structure in which one or more hydrogen atoms are substituted with hydroxyl groups in either an alkyl (meth)acrylate ester that does not have the functional group or a cyclic skeleton, or a (meth)acrylic acid ester that does not have the functional group and has a cyclic skeleton. Preferred examples of the hydroxyl group-containing (meth)acrylic acid ester 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 substituted amino group-containing (meth)acrylic acid ester include N-methylaminoethyl (meth)acrylate.

[0092] Examples of the non-acrylic monomer that constitutes the acrylic resin (b) include olefins such as ethylene and norbornene; vinyl acetate; and styrene.

[0093] Examples of the acrylic resin (b) at least a part of which is crosslinked with a crosslinking agent include those in which functional groups in the acrylic resin (b) have reacted with a crosslinking agent. The functional group may be appropriately selected depending on the type of crosslinking agent, and is not particularly limited. For example, when the crosslinking agent is a polyisocyanate compound, examples of the functional group include a hydroxyl group, a carboxyl group, an amino group, etc., and among these, a hydroxyl group, which has high reactivity with an isocyanate group, is preferred. When the crosslinking agent is an epoxy compound, examples of the functional group include a carboxyl group, an amino group, etc., and among these, a carboxyl group, which has high reactivity with an epoxy group, is preferred. However, from the viewpoint of preventing corrosion of the circuits of a wafer or chip, it is preferable that the functional group be a group other than a carboxyl group.

[0094] Examples of the acrylic resin (b) having a functional group include those obtained by polymerizing at least a monomer having the functional group. More specifically, examples of the acrylic resin (b) having a functional group include those obtained by polymerizing one or more monomers selected from the group consisting of the glycidyl group-containing (meth)acrylic ester, the hydroxyl group-containing (meth)acrylic ester, the substituted amino group-containing (meth)acrylic ester, the carboxy group-containing (meth)acrylic ester, the amino group-containing (meth)acrylic ester, and the non-acrylic monomer having a structure in which one or more hydrogen atoms have been substituted with the functional group.

[0095] In the acrylic resin (b), the proportion (content) of the amount of structural units derived from monomers having functional groups relative to the total amount of structural units constituting the resin is preferably 1 to 20 mass%, more preferably 2 to 10 mass%. When the proportion is in this range, the degree of crosslinking in the acrylic resin (b) becomes a more preferable range.

[0096] 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, in order to further suppress bleeding out during the reflow process.The weight average molecular weight (Mw) of the acrylic resin (b) is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1,500,000, in order to further improve the film-forming properties of the composition (IV).

[0097] In this specification, unless otherwise specified, the "weight average molecular weight" is a polystyrene equivalent value measured by gel permeation chromatography (GPC).

[0098] The acrylic resin (b) contained in the composition (IV) and the protective film-forming film may be one type or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0099] 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-forming film to the total mass of the protective film-forming film) is preferably 8 mass% or more, more preferably 10 mass% or more, and may be, for example, either 12 mass% or more or 14 mass% or more.

[0100] In composition (IV), the upper limit of the ratio of the content of the acrylic resin (b) to the total content of all components other than the solvent (i.e., the ratio of the content of the acrylic resin (b) in the protective film-forming film to the total mass of the protective film-forming film) is not particularly limited. In order for the protective film to exhibit a good balance between the property of suppressing bleed-out during the reflow process and other properties, the upper limit may 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.

[0101] 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-forming film to the total mass of the protective film-forming film) can be appropriately adjusted within a range set by any combination of any of the above-mentioned lower limit values ​​and upper limit values. For example, in one embodiment, the proportion is preferably 8 to 27% by mass, more preferably 10 to 25% by mass, and may be any of 12 to 23% by mass and 14 to 21% by mass.

[0102] When the composition (IV) and the protective film-forming film contain the energy ray-curable component (a) and the acrylic resin (b), the content of the energy ray-curable component (a) in the composition (IV) and the protective film-forming film is preferably 70 to 310 parts by mass, more preferably 80 to 280 parts by mass, and still more preferably 85 to 250 parts by mass, per 100 parts by mass of the content of the acrylic resin (b).

[0103] In composition (IV), the ratio of the total content of the energy ray-curable component (a) and the 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 ray-curable component (a) and the acrylic resin (b) to the total mass of the protective film-forming film) is preferably 10 to 60 mass%, and may be, for example, 20 to 50 mass%, or 30 to 45 mass%. When the ratio is in this range, the effect of using the energy ray-curable component (a) and the acrylic resin (b) is further enhanced.

[0104] [Other ingredients] The composition (IV) and the protective film-forming film may contain other components that do not fall under either the energy ray-curable component (a) or the acrylic resin (b), as long as the effects of the present invention are not impaired. Examples of the other components include a photopolymerization initiator (c); an inorganic filler (d); a coupling agent (e); a crosslinking agent (f); a colorant (g); a thermosetting component (h); a general-purpose additive (z); and a polymer (b0) that does not fall under the category of the acrylic resin (b) and does not have an energy ray-curable group (sometimes referred to in this specification as "another polymer (b0) that does not have an energy ray-curable group" or "polymer (b0)").

[0105] (Photopolymerization initiator (c)) When the composition (IV) and the protective film-forming film contain a photopolymerization initiator (c), the polymerization (curing) reaction of the energy ray-curable component (a) can be efficiently promoted.

[0106] Examples of the photopolymerization initiator include benzoin compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, benzoin methyl benzoate, and benzoin dimethyl ketal; acetophenone compounds such as acetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2,2-dimethoxy-1,2-diphenylethan-1-one, 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropan-1-one, and 2-(dimethylamino)-1-(4-morpholinophenyl)-2-benzyl-1-butanone; and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide. Examples of suitable acylphosphine oxide compounds include acylphosphine oxide compounds such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide; sulfide compounds such as benzyl phenyl sulfide and tetramethylthiuram monosulfide; α-ketol compounds such as 1-hydroxycyclohexyl phenyl ketone; azo compounds such as azobisisobutyronitrile; titanocene compounds such as titanocene; thioxanthone compounds such as thioxanthone; peroxide compounds; diketone compounds such as diacetyl; benzyl; dibenzyl; benzophenone; 2,4-diethylthioxanthone; 1,2-diphenylmethane; 2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone; and quinone compounds such as 1-chloroanthraquinone and 2-chloroanthraquinone. Examples of the photopolymerization initiator include photosensitizers such as amines.

[0107] The photopolymerization initiator (c) contained in the composition (IV) and the protective film-forming film may be one type or two or more types. When two or more types are used, the combination and ratio thereof can be selected arbitrarily. For example, a highly reactive photopolymerization initiator that is liquid at room temperature, such as 2-hydroxy-2-methyl-1-phenylpropan-1-one, can be used alone to efficiently crosslink the protective film-forming film and increase the gel fraction. A less reactive photopolymerization initiator, such as 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropan-1-one or 1-hydroxycyclohexyl-phenyl ketone, can be used in combination with a more reactive photopolymerization initiator, such as 2-(dimethylamino)-1-(4-morpholinophenyl)-2-benzyl-1-butanone, to efficiently crosslink the protective film-forming film and increase the gel fraction.

[0108] When the photopolymerization initiator (c) is used, the content of the photopolymerization initiator (c) in the composition (IV) is preferably 0.1 to 20 parts by mass, more preferably 1 to 10 parts by mass, and particularly preferably 2 to 5 parts by mass, per 100 parts by mass of the energy ray-curable component (a).

[0109] (Inorganic filler (d)) When the composition (IV) and the protective film-forming film contain an inorganic filler (d), the thermal expansion coefficient of the cured product of the protective film-forming film (e.g., a protective film) can be more easily adjusted by adjusting the amount of the inorganic filler (d) in the composition (IV) and the protective film-forming film. For example, by optimizing the thermal expansion coefficient of the protective film for the object on which the protective film is formed, the reliability of the package obtained using the protective film-forming film is further improved. In addition, by using a protective film-forming film containing an inorganic filler (d), it is possible to reduce the moisture absorption rate of the cured product of the protective film-forming film (e.g., a protective film) and improve heat dissipation properties.

[0110] Examples of the inorganic filler (d) include powders of inorganic materials such as silica, alumina, talc, calcium carbonate, titanium white, red iron oxide, silicon carbide, and boron nitride; beads made by spheronizing these inorganic materials; surface-modified products of these inorganic materials; single-crystal fibers of these inorganic materials; and glass fibers. Among these, the inorganic filler (d) is preferably silica or alumina.

[0111] The inorganic filler (d) contained in the composition (IV) and the protective film-forming film may be one type or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0112] In the composition (IV), the ratio of the content of the inorganic filler (d) to the total content of all components other than the solvent (i.e., the ratio of the content of the inorganic filler (d) in the protective film-forming film to the total mass of the protective film-forming film) is preferably 35 to 75 mass%, and may be, for example, 45 to 70 mass% or 50 to 65 mass%. By having the ratio in this range, the effect of using the inorganic filler (d) is further enhanced without impairing the properties of the protective film-forming film.

[0113] (Coupling agent (e)) When the composition (IV) and the protective film-forming film contain a coupling agent (e) having a functional group capable of reacting with an inorganic compound or an organic compound, the adhesiveness and adhesion of the protective film-forming film to an adherend are improved. In addition, the cured product of the protective film-forming film (e.g., a protective film) has improved water resistance without impairing heat resistance.

[0114] The coupling agent (e) is preferably a compound having a functional group capable of reacting with a functional group possessed by the acrylic resin (b), the energy ray-curable component (a), etc., and is more preferably a silane coupling agent. Preferred examples of the silane coupling agent include 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxymethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-(2-aminoethylamino)propyltrimethoxysilane, 3-(2- Examples of such silanes include (aminoethylamino)propylmethyldiethoxysilane, 3-(phenylamino)propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, bis(3-triethoxysilylpropyl)tetrasulfane, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, and imidazole silane.

[0115] The coupling agent (e) contained in the composition (IV) and the protective film-forming film may be one type only, or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0116] When a coupling agent (e) is used, the content of the coupling agent (e) in the composition (IV) and the protective film-forming film is preferably 0.03 to 20 parts by mass relative to 100 parts by mass of the total content of the energy ray-curable component (a) and the acrylic resin (b). When the content of the coupling agent (e) is equal to or greater than the lower limit, the effects of using the coupling agent (e), such as improved dispersibility of the inorganic filler (d) in the resin and improved adhesion of the protective film-forming film to the adherend, are more significantly obtained. When the content of the coupling agent (e) is equal to or less than the upper limit, the generation of outgassing is further suppressed.

[0117] (Crosslinking agent (f)) When the acrylic resin (b) has a functional group capable of bonding with other compounds, such as a vinyl group, (meth)acryloyl group, amino group, hydroxyl group, carboxy group, or isocyanate group, the composition (IV) and the protective film-forming film may contain a crosslinking agent (f). The crosslinking agent (f) is a component for bonding the functional group in the acrylic resin (b) with other compounds to form a crosslink, and by crosslinking in this manner, the initial adhesive strength and cohesive strength of the protective film-forming film can be adjusted.

[0118] Examples of the crosslinking agent (f) include organic polyvalent isocyanate compounds, organic polyvalent imine compounds, metal chelate crosslinking agents (crosslinking agents having a metal chelate structure), and aziridine crosslinking agents (crosslinking agents having an aziridinyl group).

[0119] Examples of the organic polyisocyanate compound include aromatic polyisocyanate compounds, aliphatic polyisocyanate compounds, and alicyclic polyisocyanate compounds (hereinafter, these compounds may be collectively referred to as "aromatic polyisocyanate compounds, etc."); trimers, isocyanurates, and adducts of the aromatic polyisocyanate compounds, etc.; and isocyanate-terminated urethane prepolymers obtained by reacting the aromatic polyisocyanate compounds, etc. with polyol compounds. The "adduct" refers to a reaction product of the aromatic polyisocyanate compound, aliphatic polyisocyanate compound, or alicyclic polyisocyanate compound with a low-molecular-weight active hydrogen-containing compound such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, or castor oil. Examples of the adduct include the xylylene diisocyanate adduct of trimethylolpropane, as described below. Furthermore, the term "isocyanate-terminated urethane prepolymer" refers to a prepolymer having a urethane bond and an isocyanate group at the end of the molecule.

[0120] More specific examples of the organic polyisocyanate compound include 2,4-tolylene diisocyanate; 2,6-tolylene diisocyanate; 1,3-xylylene diisocyanate; 1,4-xylylene diisocyanate; diphenylmethane-4,4'-diisocyanate; diphenylmethane-2,4'-diisocyanate; 3-methyldiphenylmethane diisocyanate; hexamethylene diisocyanate; isophorone diisocyanate; dicyclohexylmethane-4,4'-diisocyanate; dicyclohexylmethane-2,4'-diisocyanate; a compound in which one or more of tolylene diisocyanate, hexamethylene diisocyanate, and xylylene diisocyanate are added to all or some of the hydroxyl groups of a polyol such as trimethylolpropane; lysine diisocyanate, and the like.

[0121] Examples of the organic polyvalent imine compound include N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide), trimethylolpropane-tri-β-aziridinylpropionate, tetramethylolmethane-tri-β-aziridinylpropionate, and N,N'-toluene-2,4-bis(1-aziridinecarboxamide)triethylenemelamine.

[0122] When an organic polyisocyanate compound is used as the crosslinking agent (f), it is preferable to use a hydroxyl group-containing polymer as the acrylic resin (b). When the crosslinking agent (f) has an isocyanate group and the acrylic resin (b) has a hydroxyl group, a crosslinked structure can be easily introduced into the protective film-forming film by the reaction between the crosslinking agent (f) and the acrylic resin (b).

[0123] The crosslinking agent (f) contained in the composition (IV) and the protective film-forming film may be one type or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0124] When a crosslinking agent (f) is used, the content of the crosslinking agent (f) in the composition (IV) is preferably 0.01 to 20 parts by mass per 100 parts by mass of the acrylic resin (b). When the content of the crosslinking agent (f) is equal to or greater than the lower limit, the effect of using the crosslinking agent (f) is more pronounced. When the content of the crosslinking agent (f) is equal to or less than the upper limit, excessive use of the crosslinking agent (f) is suppressed.

[0125] (Colorant (g)) When the composition (IV) and the protective film-forming film contain the colorant (g), the light transmittance of the protective film-forming film can be adjusted by adjusting the content thereof. By adjusting the light transmittance in this manner, for example, it is possible to adjust the visibility of the laser mark when laser marking is performed on the protective film-forming film or the protective film. It is also possible to improve the design of the protective film and make grinding marks on the backside of the wafer less visible.

[0126] Examples of the colorant (g) include known colorants such as inorganic pigments, organic pigments, and organic dyes.

[0127] Examples of the organic pigments and organic dyes include aminium-based dyes, cyanine-based dyes, merocyanine-based dyes, croconium-based dyes, squarium-based dyes, azulenium-based dyes, polymethine-based dyes, naphthoquinone-based dyes, pyrylium-based dyes, phthalocyanine-based dyes, naphthalocyanine-based dyes, naphtholactam-based dyes, azo-based dyes, condensed azo-based dyes, indigo-based dyes, perinone-based dyes, perylene-based dyes, dioxazine-based dyes, quinacridone-based dyes, isoindolinone-based dyes, quinophthalone-based dyes, pyrrole-based dyes, thioindigo-based dyes, metal complex-based dyes (metal complex dyes), dithiol metal complex-based dyes, indolephenol-based dyes, triallylmethane-based dyes, anthraquinone-based dyes, naphthol-based dyes, azomethine-based dyes, benzimidazolone-based dyes, pyranthrone-based dyes, and threne-based dyes.

[0128] Examples of the inorganic pigments 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)-based pigments, and ATO (antimony tin oxide)-based pigments.

[0129] The colorant (g) contained in the composition (IV) and the protective film-forming film may be one type only, or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0130] When using a colorant (g), the content of the colorant (g) in the composition (IV) and the protective film-forming film may be adjusted appropriately depending on the purpose. For example, as described above, when improving the laser mark visibility of the protective film-forming film or the design of the protective film, or making grinding marks on the backside of the wafer less visible, the content ratio of the colorant (g) in the composition (IV) relative to the total content of all components other than the solvent (i.e., the content ratio of the colorant (g) in the protective film-forming film relative to the total mass of the protective film-forming film) is preferably 0.05 to 12 mass%, more preferably 0.05 to 9 mass%, and particularly preferably 0.1 to 7 mass%. When the ratio is equal to or greater than the lower limit, the effect of using the colorant (g) is more pronounced. When the ratio is equal to or less than the upper limit, excessive use of the colorant (g) is suppressed.

[0131] (Thermosetting component (h)) When the composition (IV) and the protective film-forming film contain the energy ray-curable component (a) and the thermosetting component (h), the adhesive strength of the protective film-forming film to the substrate is improved by heating, and the strength of the cured product of this protective film-forming film (e.g., the protective film) is also improved.

[0132] Examples of the thermosetting component (h) include epoxy-based thermosetting resins, polyimide resins, unsaturated polyester resins, etc., with epoxy-based thermosetting resins being preferred.

[0133] The epoxy thermosetting resin is composed of an epoxy resin (h1) and a thermosetting agent (h2). The epoxy thermosetting resin contained in the composition (IV) and the protective film-forming film may be one type or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0134] Epoxy resin (h1) The epoxy resin (h1) may be any known substance, such as a polyfunctional epoxy resin, a biphenyl compound, bisphenol A diglycidyl ether and its hydrogenated product, orthocresol novolac epoxy resin, a dicyclopentadiene-type epoxy resin, a biphenyl-type epoxy resin, a bisphenol A-type epoxy resin, a bisphenol F-type epoxy resin, or a phenylene skeleton-type epoxy resin, or other epoxy compounds having two or more functionalities.

[0135] The epoxy resin (h1) may be an epoxy resin having an unsaturated hydrocarbon group. Epoxy resins having an unsaturated hydrocarbon group have higher compatibility with acrylic resins than epoxy resins without an unsaturated hydrocarbon group. Therefore, by using an epoxy resin having an unsaturated hydrocarbon group, the reliability of the chip with a protective film obtained using the composite sheet for forming a protective film is improved.

[0136] Examples of epoxy resins having unsaturated hydrocarbon groups include compounds obtained by converting some of the epoxy groups of a polyfunctional epoxy resin into groups having unsaturated hydrocarbon groups. Such compounds can be obtained, for example, by subjecting epoxy groups to an addition reaction with (meth)acrylic acid or a derivative thereof. Furthermore, examples of epoxy resins having an unsaturated hydrocarbon group include compounds in which a group having an unsaturated hydrocarbon group is directly bonded to an aromatic ring or the like constituting the epoxy resin. The unsaturated hydrocarbon group is a polymerizable unsaturated group, and specific examples thereof include an ethenyl group (vinyl group), a 2-propenyl group (allyl group), a (meth)acryloyl group, and a (meth)acrylamide group, with an acryloyl group being preferred.

[0137] The number average molecular weight of the epoxy resin (h1) is not particularly limited, but from the viewpoints of the curability of the protective film-forming film and the strength and heat resistance of the protective film, it is preferably 300 to 30,000, more preferably 300 to 10,000, and particularly preferably 300 to 3,000. The epoxy equivalent of the epoxy resin (h1) is preferably 100 to 1000 g / eq, more preferably 150 to 950 g / eq.

[0138] The epoxy resin (h1) contained in the composition (IV) and the protective film-forming film may be one type or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0139] Heat hardener (H2) The heat curing agent (h2) functions as a curing agent for the epoxy resin (h1). The thermosetting agent (h2) may be, for example, a compound having two or more functional groups per molecule that can react with an epoxy group. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group, and an anhydride group of an acid group. A phenolic hydroxyl group, an amino group, or an anhydride group of an acid group is preferred, and a phenolic hydroxyl group or an amino group is more preferred.

[0140] Among the heat curing agents (h2), examples of phenolic curing agents having a phenolic hydroxyl group include polyfunctional phenolic resins, biphenols, novolac-type phenolic resins, dicyclopentadiene-type phenolic resins, and aralkyl-type phenolic resins. Among the heat curing agents (h2), examples of amine-based curing agents having an amino group include dicyandiamide.

[0141] The heat curing agent (h2) may have an unsaturated hydrocarbon group. Examples of the thermosetting agent (h2) having an unsaturated hydrocarbon group include a compound having a structure in which some of the hydroxyl groups of a phenolic resin are substituted with a group having an unsaturated hydrocarbon group, and a compound having a structure in which a group having an unsaturated hydrocarbon group is directly bonded to the aromatic ring of a phenolic resin. Examples of the unsaturated hydrocarbon group in the thermosetting agent (h2) include the same unsaturated hydrocarbon groups as those in the epoxy resin having an unsaturated hydrocarbon group described above.

[0142] When a phenol-based curing agent is used as the thermosetting agent (h2), it is preferable that the thermosetting agent (h2) has a high softening point or glass transition temperature, in order to improve the peelability of the protective film from the support sheet.

[0143] Of the thermosetting agents (h2), for example, the number average molecular weight of resin components such as polyfunctional phenolic resins, novolac-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 particularly preferably 500 to 3,000. Of the thermosetting agent (h2), the molecular weight of the non-resin component, such as biphenol or dicyandiamide, is not particularly limited, but is preferably 60 to 500, for example.

[0144] The thermosetting agent (h2) contained in the composition (IV) and the protective film-forming film may be one type or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0145] When the thermosetting component (h) is used, 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 per 100 parts by mass of the epoxy resin (h1). When the content of the thermosetting agent (h2) is equal to or greater than the lower limit, curing of the protective film-forming film proceeds more easily. When the content of the thermosetting agent (h2) is equal to or less than the upper limit, the moisture absorption rate of the protective film-forming film is reduced, and the reliability of the package obtained using the protective film-equipped chip is further improved.

[0146] When the thermosetting component (h) is used, the content of the thermosetting component (h) (for example, the total content of the epoxy resin (h1) and the thermosetting agent (h2)) in the composition (IV) and the protective film-forming film is preferably 5 to 120 parts by mass per 100 parts by mass of the acrylic resin (b). When the content of the thermosetting component (h) is in such a range, for example, the adhesive strength between the cured product of the protective film-forming film and the support sheet is suppressed, and the releasability of the support sheet is improved.

[0147] (General-purpose additive (z)) The general-purpose additive (z) may be a known one and may be selected arbitrarily depending on the purpose, and is not particularly limited. Preferred general-purpose additives (z) include, for example, plasticizers, antistatic agents, antioxidants, gettering agents, and ultraviolet absorbers.

[0148] The general-purpose additive (z) contained in the composition (IV) and the protective film-forming film may be one type only, or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0149] When the general-purpose additive (z) is used, the content of the general-purpose additive (z) in the composition (IV) and the protective film-forming film is not particularly limited and may be appropriately selected depending on the purpose. For example, when the general-purpose additive (z) is an ultraviolet absorber, the ratio of the content of the general-purpose additive (z) (ultraviolet absorber) to the total content of all components other than the solvent in the composition (IV) (i.e., the ratio of the content of the general-purpose 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 mass%. When the ratio is equal to or greater than the lower limit, the effect of using the general-purpose additive (z) is more pronounced. When the ratio is equal to or less than the upper limit, excessive use of the general-purpose additive (z) is suppressed.

[0150] (Other polymers (b0) not having energy ray-curable groups) The other polymer (b0) having no energy ray-curable group imparts film-forming properties to the protective film-forming film. The polymer (b0) is not particularly limited as long as it does not fall under the category of the acrylic resin (b). The polymer (b0) may be at least partially crosslinked with a crosslinking agent, or may not be crosslinked.

[0151] Examples of the polymer (b0) include an acrylic resin having a weight-average molecular weight of more than 1,100,000, an acrylic resin having a dispersity of 3.0 or less (in this specification, these acrylic resins may be referred to as "other acrylic resins"); and a polymer other than an acrylic resin that does not have an energy ray-curable group.

[0152] Examples of the other acrylic resin include those similar to the acrylic resin (b), except that the other acrylic resin has a weight average molecular weight of more than 1,100,000 or a dispersity of 3.0 or less.

[0153] Examples of polymers other than acrylic resins that do not have an energy ray-curable group include urethane resins, phenoxy resins, silicone resins, and saturated polyester resins.

[0154] The weight average molecular weight (Mw) of the polymer other than the acrylic resin that does not have an energy ray-curable group is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1,500,000, in order to improve the film-forming properties of the composition (IV).

[0155] The polymer (b0) contained in the composition (IV) and the protective film-forming film may be one type or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0156] In the composition (IV) and the protective film-forming film, the content of the polymer (b0) is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, and even more preferably 1 part by mass or less, relative to 100 parts by mass of the content of the acrylic resin (b), and it is particularly preferable that it is 0 parts by mass, that is, the composition (IV) and the protective film-forming film do not contain the polymer (b0). When the content of the polymer (b0) is equal to or less than the upper limit, bleeding out during the reflow process described above is further suppressed.

[0157] [solvent] Composition (IV) preferably further contains a solvent, which makes composition (IV) easier to handle. The solvent is not particularly limited, but preferred examples include hydrocarbons such as toluene and xylene; alcohols such as methanol, ethanol, 2-propanol, isobutyl alcohol (2-methylpropan-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 having an amide bond) such as dimethylformamide and N-methylpyrrolidone. The composition (IV) may contain only one type of solvent, or two or more types of solvents. When two or more types of solvents are contained, the combination and ratio thereof can be selected arbitrarily.

[0158] A more preferred example of the solvent contained in composition (IV) is methyl ethyl ketone, which allows the components contained in composition (IV) to be mixed more uniformly.

[0159] The content of the solvent in the composition (IV) is not particularly limited, and may be appropriately selected depending on, for example, the types of components other than the solvent.

[0160] <<Method of manufacturing the protective film-forming composition>> The energy ray-curable protective film-forming composition such as composition (IV) can be obtained by blending the components that constitute it. The order of addition of the components when blending is not particularly limited, and two or more components may be added simultaneously. The method for mixing the components during blending is not particularly limited, and may be appropriately selected from known methods such as a method of mixing by rotating a stirrer or stirring blades, a method of mixing using a mixer, or a method of mixing by adding ultrasound. The temperature and time for adding and mixing each component are not particularly limited as long as the components do not deteriorate, and may be adjusted appropriately. A temperature of 15 to 30°C is preferred.

[0161] 1 is a cross-sectional view schematically showing an example of a protective film-forming film of the present embodiment. In the drawings used in the following description, for the sake of convenience, in order to make the features of the present invention easier to understand, essential parts may be shown enlarged, and the dimensional ratios of each component may not necessarily be the same as in reality.

[0162] The protective film-forming film 13 shown here has a first release film 151 on one of its surfaces (sometimes referred to as the "first surface" in this specification) 13a, and a second release film 152 on the other surface (sometimes referred to as the "second surface" in this specification) 13b opposite the first surface 13a. Such a protective film-forming film 13 is suitable for storage in the form of a roll, for example.

[0163] The protective film-forming film 13 has the above-mentioned properties. The protective film-forming film 13 can be formed using the above-mentioned protective film-forming composition.

[0164] The first release film 151 and the second release film 152 may both be known films. The first release film 151 and the second release film 152 may be the same as each other, or may be different from each other, for example, in that the peeling force required to peel them from the protective film-forming film 13 is different from each other.

[0165] 1, one of the first release film 151 and the second release film 152 is removed, and the resulting exposed surface becomes the surface to be attached to the back surface of a wafer (not shown). Then, the other of the first release film 151 and the second release film 152 is removed, and the resulting exposed surface becomes the surface to be attached to a support sheet or a dicing sheet, which will be described later.

[0166] Figure 1 shows an example in which a release film is provided on both sides (first side 13a, second side 13b) of the protective film-forming film 13, but the release film may be provided on only one side of the protective film-forming film 13, i.e., only the first side 13a or only the second side 13b.

[0167] The protective film-forming film of this embodiment can be attached to the back surface of the wafer without using a support sheet described later. In this case, a release film may be provided on the surface of the protective film-forming film opposite to the surface attached to the wafer, and this release film may be removed at an appropriate time.

[0168] On the other hand, the protective film-forming film of this embodiment can be used in combination with a support sheet described later to form a composite sheet for forming a protective film, which can perform both protective film formation and dicing. Such a composite sheet for forming a protective film will be described below.

[0169] ◇Composite sheet for forming protective film A composite sheet for forming a protective film according to one embodiment of the present invention comprises a support sheet and a protective film-forming film provided on one side of the support sheet, and the protective film-forming film is the protective film-forming film according to one embodiment of the present invention described above. The composite sheet for forming a protective film of this embodiment includes the protective film-forming film, and therefore when a protective film is formed, bleeding out due to the reflow process described above is suppressed.

[0170] In this specification, as long as the laminated structure of the support sheet and the cured product of the protective film-forming film is maintained even after the protective film-forming film has hardened, this laminated structure is referred to as a "composite sheet for forming a protective film."

[0171] Each layer constituting the composite sheet for forming a protective film will be described in detail below.

[0172] ◎Support sheet The support sheet may consist of one layer (single layer) or two or more layers. When the support sheet consists of multiple layers, the constituent materials and thicknesses of these multiple layers may be the same or different, and the combination of these multiple layers is not particularly limited as long as it does not impair the effects of the present invention.

[0173] The support sheet is preferably transparent, and may be colored depending on the purpose. In this embodiment in which the protective film-forming film has energy ray curability, the support sheet is preferably one that transmits energy rays.

[0174] Examples of the support sheet include one comprising a substrate and a pressure-sensitive adhesive layer provided on one surface of the substrate, one consisting of only the substrate, etc. When the support sheet comprises a pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer is disposed between the substrate and the protective film-forming film in the composite sheet for forming a protective film.

[0175] When a support sheet having a substrate and a pressure-sensitive adhesive layer is used, the adhesion and peelability between the support sheet and the protective film-forming film in the composite sheet for forming a protective film can be easily adjusted. When a support sheet consisting of only a substrate is used, a composite sheet for forming a protective film can be produced at low cost.

[0176] Examples of the composite sheet for forming a protective film according to this embodiment will be described below for each type of support sheet with reference to the drawings.

[0177] FIG. 2 is a cross-sectional view schematically illustrating an example of the composite sheet for forming a protective film according to the present embodiment. In FIG. 2 and subsequent figures, the same components as those shown in the figures already described are given the same reference numerals as in the figures already described, and detailed description thereof will be omitted.

[0178] The composite sheet 101 for forming a protective film shown here is composed of a support sheet 10 and a protective film forming film 13 provided on one side 10a of the support sheet 10 (sometimes referred to as the "first side" in this specification). The support sheet 10 is configured to include a base material 11 and an adhesive layer 12 provided on one surface (first surface) 11a of the base material 11. In the composite sheet 101 for forming a protective film, the adhesive layer 12 is disposed between the base material 11 and the protective film-forming film 13. That is, the composite sheet 101 for forming a protective film is configured by laminating a substrate 11, a pressure-sensitive adhesive layer 12, and a protective film-forming film 13 in this order in the thickness direction. The first surface 10a of the support sheet 10 is the same as the surface 12a of the pressure-sensitive adhesive layer 12 opposite to the substrate 11 side (sometimes referred to as the "first surface" in this specification).

[0179] The composite sheet 101 for forming a protective film further includes a jig adhesive layer 16 and a release film 15 on the protective film-forming film 13 . In the composite sheet 101 for forming a protective film, a protective film-forming film 13 is laminated over the entire or almost entire first surface 12a of the pressure-sensitive adhesive layer 12, and a jig adhesive layer 16 is laminated over a portion of the surface 13a of the protective film-forming film 13 opposite the pressure-sensitive adhesive layer 12 side (sometimes referred to as the "first surface" in this specification), i.e., the area near the peripheral portion. Furthermore, a release film 15 is laminated over an area of ​​the first surface 13a of the protective film-forming film 13 where the jig adhesive layer 16 is not laminated, and over the surface 16a of the jig adhesive layer 16 opposite the protective film-forming film 13 side (sometimes referred to as the "first surface" in this specification). A support sheet 10 is provided on the surface 13b of the protective film-forming film 13 opposite the first surface 13a (sometimes referred to as the "second surface" in this specification).

[0180] Not only in the case of the composite sheet 101 for forming a protective film, but also in the composite sheet for forming a protective film of this embodiment, the release film (for example, release film 15 shown in Figure 1) has an optional configuration, and the composite sheet for forming a protective film of this embodiment may or may not have a release film.

[0181] The jig adhesive layer 16 is used to fix the composite sheet for forming a protective film 101 to a jig such as a ring frame. The jig adhesive layer 16 may have, for example, a single-layer structure containing an adhesive component, or a multi-layer structure including a core sheet and layers containing adhesive components provided on both sides of the core sheet.

[0182] The composite sheet 101 for forming a protective film is used by removing the release film 15, attaching the back surface of the wafer to the first surface 13a of the protective film forming film 13, and further attaching the first surface 16a of the jig adhesive layer 16 to a jig such as a ring frame.

[0183] FIG. 3 is a cross-sectional view schematically showing another example of the composite sheet for forming a protective film according to the present embodiment. The composite sheet 102 for forming a protective film shown here is the same as the composite sheet 101 for forming a protective film shown in Figure 2, except that the shape and size of the protective film-forming film are different and the adhesive layer for the jig is laminated on the first surface of the pressure-sensitive adhesive layer rather than on the first surface of the protective film-forming film.

[0184] More specifically, in the composite sheet 102 for forming a protective film, the protective film-forming film 23 is laminated in a partial region of the first surface 12a of the pressure-sensitive adhesive layer 12, i.e., in a region on the central side in the width direction (left-right direction in FIG. 3 ) of the pressure-sensitive adhesive layer 12. Furthermore, in a region of the first surface 12a of the pressure-sensitive adhesive layer 12 where the protective film-forming film 23 is not laminated, a jig adhesive layer 16 is laminated so as to surround the protective film-forming film 23 from the outside in the width direction without contacting it. A release film 15 is laminated on a surface 23a of the protective film-forming film 23 opposite the pressure-sensitive adhesive layer 12 side (sometimes referred to as the "first surface" in this specification) and on the first surface 16a of the jig adhesive layer 16. A support sheet 10 is provided on a surface 23b of the protective film-forming film 23 opposite the first surface 23a (sometimes referred to as the "second surface" in this specification).

[0185] FIG. 4 is a cross-sectional view schematically showing still another example of the composite sheet for forming a protective film according to the present embodiment. The composite sheet 103 for forming a protective film shown here is the same as the composite sheet 102 for forming a protective film shown in FIG. 3, except that it does not include the jig adhesive layer 16.

[0186] FIG. 5 is a cross-sectional view schematically showing still another example of the composite sheet for forming a protective film of the present embodiment. The composite sheet 104 for forming a protective film shown here is the same as the composite sheet 101 for forming a protective film shown in FIG. 2, except that it is configured to include a support sheet 20 instead of the support sheet 10.

[0187] The support sheet 20 is made of only the substrate 11 . That is, the protective film-forming composite sheet 104 is configured by laminating the base material 11 and the protective film-forming film 13 in the thickness direction. The surface (first surface) 20 a of the support sheet 20 on the protective film-forming film 13 side is the same as the first surface 11 a of the base material 11 . The substrate 11 has adhesiveness at least on its first surface 11a.

[0188] The composite sheet for forming a protective film of this embodiment is not limited to that shown in Figures 2 to 5, and may be one in which some of the configurations shown in Figures 2 to 5 have been changed or deleted, or one in which other configurations have been added to those described above, within the scope that does not impair the effects of the present invention.

[0189] Next, each layer constituting the support sheet will be described in more detail.

[0190] ○Base material The substrate is in the form of a sheet or film, and examples of the constituent materials thereof include various resins. Examples of the resin include polyethylenes 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 resin; ethylene-based copolymers (copolymers obtained using ethylene as a monomer) such as ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester copolymer, and ethylene-norbornene copolymer; and vinyl chloride-based resins (copolymers obtained using vinyl chloride as a monomer) such as polyvinyl chloride and vinyl chloride copolymer. resins containing aromatic rings); polystyrene; polycycloolefin; polyesters such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyethylene isophthalate, polyethylene-2,6-naphthalenedicarboxylate, and wholly aromatic polyesters in which all structural units have aromatic cyclic groups; copolymers of two or more of the above polyesters; poly(meth)acrylic acid esters; polyurethanes; polyurethane acrylates; polyimides; polyamides; polycarbonates; fluororesins; polyacetals; modified polyphenylene oxides; polyphenylene sulfides; polysulfones; and polyether ketones. Further, examples of the resin include polymer alloys such as mixtures of the polyester and other resins. The polymer alloys of the polyester and other resins preferably contain a relatively small amount of resin other than polyester. Examples of the resin include crosslinked resins in which one or more of the resins exemplified above are crosslinked; and modified resins such as ionomers using one or more of the resins exemplified above.

[0191] The resin constituting the substrate may be one type only, or two or more types, and when two or more types are used, the combination and ratio thereof can be selected arbitrarily.

[0192] The substrate may consist of one layer (single layer), or may consist of two or more layers. When the substrate consists of multiple layers, these multiple layers may be the same or different from each other, and the combination of these multiple layers is not particularly limited.

[0193] The thickness of the substrate is preferably 50 to 300 μm, more preferably 60 to 100 μm. When the thickness of the substrate is within this range, the flexibility of the composite sheet for forming a protective film and the suitability for attachment to a wafer are further improved. Here, the "thickness of the substrate" means the thickness of the entire substrate, and for example, the thickness of a substrate consisting of multiple layers means the total thickness of all layers that make up the substrate.

[0194] The substrate may contain, in addition to the main constituent materials such as the resin, various known additives such as fillers, colorants, antioxidants, organic lubricants, catalysts, and softeners (plasticizers).

[0195] The substrate is preferably transparent, and may be colored depending on the purpose, or may have other layers vapor-deposited thereon. In this embodiment in which the protective film-forming film has energy ray curability, the substrate is preferably one that transmits energy rays.

[0196] In order to adjust the adhesiveness to a layer (e.g., a pressure-sensitive adhesive layer, a protective film-forming film, or the other layer) provided thereon, the surface of the substrate may be subjected to roughening treatment such as sandblasting or solvent treatment; oxidation treatment such as corona discharge treatment, electron beam irradiation treatment, plasma treatment, ozone / ultraviolet irradiation treatment, flame treatment, chromic acid treatment, or hot air treatment; lipophilic treatment; hydrophilic treatment; etc. The surface of the substrate may also be treated with a primer.

[0197] The substrate may contain a specific range of components (for example, a resin) to provide adhesiveness on at least one surface.

[0198] The substrate can be produced by a known method. For example, a substrate containing a resin can be produced by molding a resin composition containing the resin.

[0199] Adhesive layer The pressure-sensitive adhesive layer is in the form of a sheet or film and contains a pressure-sensitive adhesive. Examples of the adhesive include adhesive resins such as acrylic resins, urethane resins, rubber-based resins, silicone resins, epoxy-based resins, polyvinyl ethers, polycarbonates, and ester-based resins.

[0200] In this specification, the term "adhesive resin" includes both a resin having adhesive properties and a resin having adhesive properties. For example, the adhesive resin includes not only resins that are adhesive by themselves, but also resins that become adhesive when used in combination with other components such as additives, and resins that become adhesive in the presence of a trigger such as heat or water.

[0201] The adhesive layer may consist of one layer (single layer), or may consist of two or more layers. When it consists of multiple layers, these multiple layers may be the same or different from each other, and the combination of these multiple layers is not particularly limited.

[0202] The thickness of the pressure-sensitive adhesive layer is not particularly limited, but is preferably 1 to 100 μm, more preferably 1 to 60 μm, and particularly preferably 1 to 30 μm. Here, "thickness of the adhesive layer" means the thickness of the entire adhesive layer, and for example, the thickness of an adhesive layer consisting of multiple layers means the total thickness of all layers that make up the adhesive layer.

[0203] The pressure-sensitive adhesive layer is preferably transparent, and may be colored depending on the purpose. In this embodiment in which the protective film-forming film has energy ray curability, the pressure-sensitive adhesive layer is preferably one that transmits energy rays.

[0204] The pressure-sensitive adhesive layer may be either energy ray-curable or non-energy ray-curable. The physical properties of the energy ray-curable pressure-sensitive adhesive layer can be adjusted before and after curing. For example, by curing the energy ray-curable pressure-sensitive adhesive layer before picking up the protective film-equipped chip described below, the protective film-equipped chip can be more easily picked up.

[0205] The pressure-sensitive adhesive layer can be formed using a pressure-sensitive adhesive composition containing a pressure-sensitive adhesive. For example, the pressure-sensitive adhesive composition can be applied to a surface on which the pressure-sensitive adhesive layer is to be formed, and then dried as necessary to form the pressure-sensitive adhesive layer at the desired location. The ratio of the contents of the components that do not vaporize at room temperature in the pressure-sensitive adhesive composition is usually the same as the ratio of the contents of the components in the pressure-sensitive adhesive layer.

[0206] The application and drying of the pressure-sensitive adhesive composition can be carried out, for example, by the same method as in the application and drying of the above-mentioned composition for forming a protective film.

[0207] When a pressure-sensitive adhesive layer is provided on a substrate, for example, a pressure-sensitive adhesive composition may be applied to the substrate and dried as necessary. Alternatively, for example, a pressure-sensitive adhesive composition may be applied to a release film and dried as necessary to form a pressure-sensitive adhesive layer on the release film, and the exposed surface of this pressure-sensitive adhesive layer may be attached to one surface of the substrate to laminate the pressure-sensitive adhesive layer on the substrate. In this case, the release film may be removed at any time during the production process or use process of the composite sheet for forming a protective film.

[0208] When the adhesive layer is energy ray-curable, examples of the energy ray-curable adhesive composition include adhesive composition (I-1) containing a non-energy ray-curable adhesive resin (I-1a) (hereinafter sometimes abbreviated as "adhesive resin (I-1a)") and an energy ray-curable compound; adhesive composition (I-2) containing an energy ray-curable adhesive resin (I-2a) (hereinafter sometimes abbreviated as "adhesive resin (I-2a)") in which an unsaturated group has been introduced into the side chain of the non-energy ray-curable adhesive resin (I-1a); adhesive composition (I-3) containing the adhesive resin (I-2a) and an energy ray-curable compound; and the like.

[0209] When the pressure-sensitive adhesive layer is non-energy ray-curable, examples of the non-energy ray-curable pressure-sensitive adhesive composition include a pressure-sensitive adhesive composition (I-4) containing the non-energy ray-curable pressure-sensitive adhesive resin (I-1a).

[0210] [Non-energy ray curable adhesive resin (I-1a)] The adhesive resin (I-1a) is preferably an acrylic resin.

[0211] Examples of the acrylic resin include acrylic polymers having at least a structural unit derived from a (meth)acrylic acid alkyl ester. The (meth)acrylic acid alkyl ester may be, for example, one in which the alkyl group constituting the alkyl ester has 1 to 20 carbon atoms, and the alkyl group is preferably linear or branched.

[0212] The acrylic polymer preferably further contains a structural unit derived from a functional group-containing monomer in addition to the structural unit derived from the (meth)acrylic acid alkyl ester. Examples of the functional group-containing monomer include those in which the functional group reacts with a crosslinking agent described below to become a crosslinking starting point, and those in which the functional group reacts with a functional group such as an isocyanate group or a glycidyl group in an unsaturated group-containing compound described below to enable the introduction of an unsaturated group into a side chain of an acrylic polymer.

[0213] Examples of the functional group-containing monomer include a hydroxyl group-containing monomer, a carboxyl group-containing monomer, an amino group-containing monomer, and an epoxy group-containing monomer.

[0214] The acrylic polymer may further contain structural units derived from other monomers in addition to the structural units derived from the (meth)acrylic acid alkyl ester and the structural units derived from the functional group-containing monomer. The other monomer is not particularly limited as long as it is copolymerizable with the (meth)acrylic acid alkyl ester or the like. Examples of the other monomers include styrene, α-methylstyrene, vinyltoluene, vinyl formate, vinyl acetate, acrylonitrile, and acrylamide.

[0215] In the pressure-sensitive adhesive composition (I-1), pressure-sensitive adhesive composition (I-2), pressure-sensitive adhesive composition (I-3) and pressure-sensitive adhesive composition (I-4) (hereinafter, these pressure-sensitive adhesive compositions are collectively referred to as "pressure-sensitive adhesive compositions (I-1) to (I-4)"), the structural unit contained in the acrylic resin such as the acrylic polymer may be of one type or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0216] In the acrylic polymer, the proportion of the amount of structural units derived from functional group-containing monomers relative to the total amount of structural units is preferably 1 to 35% by mass.

[0217] The adhesive resin (I-1a) contained in the adhesive composition (I-1) or (I-4) may be one type or two or more types, and when two or more types are contained, the combination and ratio thereof can be selected arbitrarily.

[0218] In the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition (I-1) or the pressure-sensitive adhesive composition (I-4), the content of the pressure-sensitive adhesive resin (I-1a) relative to the total mass of the pressure-sensitive adhesive layer is preferably 5 to 99 mass%, and may be, for example, any one of 25 to 95 mass%, 45 to 95 mass%, and 65 to 95 mass%.

[0219] [Energy ray curable adhesive resin (I-2a)] The adhesive resin (I-2a) can be obtained, for example, by reacting a functional group in the adhesive resin (I-1a) with an unsaturated group-containing compound having an energy ray-polymerizable unsaturated group.

[0220] The unsaturated group-containing compound is a compound that, in addition to the energy ray-polymerizable unsaturated group, further has a group that can bond to the adhesive resin (I-1a) by reacting with a functional group in the adhesive resin (I-1a). Examples of the energy ray-polymerizable unsaturated group include a (meth)acryloyl group, a vinyl group (ethenyl group), and an allyl group (2-propenyl group), and the (meth)acryloyl group is preferred. Examples of groups capable of bonding to functional groups in the adhesive resin (I-1a) include isocyanate groups and glycidyl groups capable of bonding to hydroxyl groups or amino groups, and hydroxyl groups and amino groups capable of bonding to carboxyl groups or epoxy groups.

[0221] Examples of the unsaturated group-containing compound include (meth)acryloyloxyethyl isocyanate, (meth)acryloyl isocyanate, and glycidyl (meth)acrylate.

[0222] The adhesive resin (I-2a) contained in the adhesive composition (I-2) or (I-3) may be one type or two or more types, and when two or more types are contained, the combination and ratio thereof can be selected arbitrarily.

[0223] In the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition (I-2) or (I-3), the content of the pressure-sensitive adhesive resin (I-2a) relative to the total mass of the pressure-sensitive adhesive layer is preferably 5 to 99 mass %.

[0224] [Energy ray curable compounds] The energy ray-curable compound contained in the pressure-sensitive adhesive composition (I-1) or (I-3) includes a monomer or oligomer having an energy ray-polymerizable unsaturated group and capable of being cured by irradiation with energy rays.

[0225] Among the energy ray-curable compounds, examples of the monomer include polyvalent (meth)acrylates such as trimethylolpropane tri(meth)acrylate, pentaerythritol (meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butylene glycol di(meth)acrylate, and 1,6-hexanediol (meth)acrylate; urethane (meth)acrylate; polyester (meth)acrylate; polyether (meth)acrylate; and epoxy (meth)acrylate. Among the energy ray-curable compounds, examples of oligomers include oligomers that are polymers of the above-exemplified monomers.

[0226] The pressure-sensitive adhesive composition (I-1) or (I-3) may contain only one type of energy ray-curable compound, or two or more types. When two or more types are contained, the combination and ratio thereof can be selected arbitrarily.

[0227] In the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition (I-1) or (I-3), the content of the energy ray-curable compound relative to the total mass of the pressure-sensitive adhesive layer is preferably 1 to 95 mass %.

[0228] [Crosslinking agent] When the adhesive resin (I-1a) is an acrylic polymer having, in addition to a structural unit derived from a (meth)acrylic acid alkyl ester, a structural unit derived from a functional group-containing monomer, the adhesive composition (I-1) or (I-4) preferably further contains a crosslinking agent. Furthermore, when the adhesive resin (I-2a) is, for example, an acrylic polymer having structural units derived from functional group-containing monomers similar to those in the adhesive resin (I-1a), the adhesive composition (I-2) or (I-3) may further contain a crosslinking agent.

[0229] The crosslinking agent reacts with the functional group to crosslink the adhesive resins (I-1a) together or the adhesive resins (I-2a) together, for example. Examples of crosslinking agents include isocyanate-based crosslinking agents (crosslinking agents having an isocyanate group) such as tolylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, and adducts of these diisocyanates; epoxy-based crosslinking agents (crosslinking agents having a glycidyl group) such as ethylene glycol glycidyl ether; aziridine-based crosslinking agents (crosslinking agents having an aziridinyl group) such as hexa[1-(2-methyl)-aziridinyl]triphosphatriazine; metal chelate-based crosslinking agents (crosslinking agents having a metal chelate structure) such as aluminum chelate; and isocyanurate-based crosslinking agents (crosslinking agents having an isocyanuric acid skeleton).

[0230] The crosslinking agents contained in the pressure-sensitive adhesive compositions (I-1) to (I-4) may be one type only, or two or more types. When two or more types are contained, the combination and ratio thereof can be selected arbitrarily.

[0231] In the pressure-sensitive adhesive composition (I-1) or (I-4), the content of the crosslinking agent is preferably 0.01 to 50 parts by mass, and may be, for example, 1 to 40 parts by mass, 5 to 35 parts by mass, or 10 to 30 parts by mass, relative to 100 parts by mass of the pressure-sensitive adhesive resin (I-1a). In the pressure-sensitive adhesive composition (I-2) or (I-3), the content of the crosslinking agent is preferably 0.01 to 50 parts by mass per 100 parts by mass of the pressure-sensitive adhesive resin (I-2a).

[0232] [Photopolymerization initiator] The pressure-sensitive adhesive compositions (I-1), (I-2) and (I-3) (hereinafter collectively referred to as "pressure-sensitive adhesive compositions (I-1) to (I-3)") may further contain a photopolymerization initiator. The pressure-sensitive adhesive compositions (I-1) to (I-3) containing a photopolymerization initiator undergo a sufficient curing reaction even when irradiated with relatively low-energy energy rays such as ultraviolet light.

[0233] Examples of the photopolymerization initiator include the same as the photopolymerization initiator (c) described above.

[0234] The photopolymerization initiators contained in the pressure-sensitive adhesive compositions (I-1) to (I-3) may be one type only, or two or more types. When two or more types are contained, the combination and ratio thereof can be selected arbitrarily.

[0235] In the pressure-sensitive adhesive composition (I-1), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass relative to 100 parts by mass of the content of the energy ray-curable compound. In the pressure-sensitive adhesive composition (I-2), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass per 100 parts by mass of the pressure-sensitive adhesive resin (I-2a). In the pressure-sensitive adhesive composition (I-3), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass relative to 100 parts by mass of the total content of the pressure-sensitive adhesive resin (I-2a) and the energy ray-curable compound.

[0236] [Other additives] The pressure-sensitive adhesive compositions (I-1) to (I-4) may contain other additives that do not fall under any of the above-mentioned components, as long as the effects of the present invention are not impaired. Examples of the other additives include known additives such as antistatic agents, antioxidants, softeners (plasticizers), fillers, rust inhibitors, colorants (pigments, dyes), sensitizers, tackifiers, reaction retarders, and crosslinking accelerators (catalysts). The reaction retarder is a component that inhibits the progress of unintended crosslinking reactions in the pressure-sensitive adhesive compositions (I-1) to (I-4) during storage due to the action of a catalyst mixed in the pressure-sensitive adhesive compositions (I-1) to (I-4). Examples of the reaction retarder include those that form chelate complexes by chelating with the catalyst, and more specifically, those having two or more carbonyl groups (-C(=O)-) in one molecule.

[0237] The other additives contained in the pressure-sensitive adhesive compositions (I-1) to (I-4) may be one type only, or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0238] The content of other additives in the pressure-sensitive adhesive compositions (I-1) to (I-4) is not particularly limited and may be selected appropriately depending on the type of additive.

[0239] [solvent] The pressure-sensitive adhesive compositions (I-1) to (I-4) may contain a solvent, which improves the suitability of the pressure-sensitive adhesive compositions (I-1) to (I-4) for application to a surface to be coated.

[0240] The solvent is preferably an organic solvent, and examples of the organic solvent 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.

[0241] The pressure-sensitive adhesive compositions (I-1) to (I-4) may contain only one type of solvent, or two or more types, and when two or more types are contained, the combination and ratio thereof can be selected arbitrarily.

[0242] The content of the solvent in the pressure-sensitive adhesive compositions (I-1) to (I-4) is not particularly limited and may be adjusted appropriately.

[0243] Method for producing pressure-sensitive adhesive composition The pressure-sensitive adhesive compositions such as pressure-sensitive adhesive compositions (I-1) to (I-4) can be obtained by blending the pressure-sensitive adhesive and, if necessary, components other than the pressure-sensitive adhesive, for constituting the pressure-sensitive adhesive composition. The pressure-sensitive adhesive composition can be produced by the same method as the above-described composition for forming a protective film, except that the types of ingredients used are different.

[0244] ◇Manufacturing method of composite sheet for forming protective film The composite sheet for forming a protective film can be produced by laminating the above-mentioned layers in a corresponding positional relationship and adjusting the shapes of some or all of the layers as necessary. The method for forming each layer is as described above.

[0245] For example, when a support sheet is produced by laminating a pressure-sensitive adhesive layer on a substrate, the pressure-sensitive adhesive composition may be applied to the substrate and dried as necessary. Alternatively, a pressure-sensitive adhesive layer can be laminated on a substrate by coating a pressure-sensitive adhesive composition on a release film, drying it as needed to form a pressure-sensitive adhesive layer on the release film, and then laminating the exposed surface of this pressure-sensitive adhesive layer to one surface of a substrate. In this case, it is preferable to coat the pressure-sensitive adhesive composition on the release-treated surface of the release film. Up to this point, the case where a pressure-sensitive adhesive layer is laminated on a substrate has been taken as an example, but the above-mentioned method can also be applied to the case where, for example, a layer other than a pressure-sensitive adhesive layer is laminated on a substrate.

[0246] On the other hand, for example, when a protective film-forming film is further laminated on a pressure-sensitive adhesive layer already laminated on a substrate, it is possible to coat a protective film-forming composition on the pressure-sensitive adhesive layer to directly form the protective film-forming film. Layers other than the protective film-forming film can also be laminated on the pressure-sensitive adhesive layer in a similar manner using a composition for forming this layer. In this way, when a new layer (hereinafter abbreviated as "second layer") is formed on any layer (hereinafter abbreviated as "first layer") already laminated on the substrate to form a continuous two-layer laminate structure (in other words, a laminate structure of the first layer and the second layer), a method can be applied in which a composition for forming the second layer is coated on the first layer and dried as necessary. However, it is preferable to form the second layer in advance on a release film using a composition for forming the second layer, and then bond the exposed surface of the second layer opposite the side in contact with the release film to the exposed surface of the first layer to form a continuous two-layer laminate structure. In this case, it is preferable to coat the composition on the release-treated surface of the release film. The release film can be removed as needed after the laminate structure is formed. Here, we have given an example of laminating a protective film-forming film onto an adhesive layer, but the target laminate structure can be selected arbitrarily, for example, when laminating a layer (film) other than a protective film-forming film onto an adhesive layer.

[0247] In this way, all layers other than the substrate that make up the composite sheet for forming a protective film can be formed in advance on a release film and then laminated by bonding it to the surface of the desired layer, so the composite sheet for forming a protective film can be manufactured by appropriately selecting the layers that will undergo this process as needed.

[0248] The composite sheet for forming a protective film is usually stored with a release film attached to the surface of the outermost layer (for example, the protective film-forming film) opposite the support sheet. Therefore, a composition for forming a layer constituting the outermost layer, such as a protective film-forming composition, is applied to this release film (preferably its release-treated surface) and dried as necessary to form a layer constituting the outermost layer on the release film, and the remaining layers are laminated by any of the methods described above on the exposed surface opposite the side in contact with the release film of this layer, and the release film is not removed and the composite sheet for forming a protective film with a release film attached is obtained.

[0249] ◇Manufacturing method of chips with protective film (method of using protective film forming film and protective film forming composite sheet) The protective film-forming film and the composite sheet for forming a protective film can be used to manufacture the chip with the protective film. That is, a method for manufacturing a chip with a protective film according to one embodiment of the present invention is a method for manufacturing a chip with a protective film, which includes a chip and a protective film provided on the back surface of the chip, and the method for manufacturing the chip with a protective film includes a step of: attaching the protective film-forming film according to one embodiment of the present invention to the back surface of a wafer to produce a first laminated film in which the protective film-forming film and the wafer are laminated in their thickness direction; or attaching the protective film-forming film in the protective film-forming composite sheet according to one embodiment of the present invention to the back surface of a wafer to produce a first laminated composite sheet in which the support sheet, protective film-forming film, and wafer are laminated in this order in their thickness direction (sometimes referred to in this specification as a "bonding step"); and curing the protective film-forming film in the first laminated film or in the first laminated composite sheet with energy rays to form the protective film, to produce a second laminated film in which the protective film and the wafer are laminated in their thickness direction; The method includes the steps of: preparing a second laminated composite sheet in which a sheet, a protective film, and a wafer are laminated in this order in the thickness direction (sometimes referred to herein as the "curing process"); dividing the wafer in the second laminated film and cutting the protective film while a dicing sheet is provided on the protective film side of the second laminated film to prepare a third laminated film in which a plurality of protective film-coated chips are fixed on the dicing sheet, or dividing the wafer in the second laminated composite sheet and cutting the protective film to prepare a third laminated composite sheet in which a plurality of protective film-coated chips are fixed on the support sheet (sometimes referred to herein as the "division process"); and picking up the protective film-coated chips in the third laminated film by either separating them from the dicing sheet or separating them from the support sheet (sometimes referred to herein as the "pickup process").

[0250] Below, with reference to the drawings, we will explain in order a method for manufacturing a chip with a protective film in which a protective film-forming film that is not part of a composite sheet for forming a protective film is attached to the back surface of a wafer (sometimes referred to in this specification as "manufacturing method 1"), and a method for manufacturing a chip with a protective film in which a protective film-forming film included in a composite sheet for forming a protective film is attached to the back surface of a wafer (sometimes referred to in this specification as "manufacturing method 2").

[0251] <<Manufacturing method 1>> 6 is a cross-sectional view for schematically explaining manufacturing method 1. Here, manufacturing method 1 will be explained using an example in which the protective film-forming film 13 shown in FIG. In the bonding step of manufacturing method 1, as shown in Fig. 6(a), the above-mentioned protective film-forming film 13 is bonded to the back surface 9b of the wafer 9 to produce a first laminated film 601 in which the protective film-forming film 13 and the wafer 9 are laminated in their thickness direction. A first surface 13a of the protective film-forming film 13 is bonded to the back 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. Here, the case is shown in which the first peelable film 151 is removed from the protective film-forming film 13 shown in Figure 1 and the first surface 13a of the protective film-forming film 13 is attached to the back surface 9b of the wafer 9, but the second peelable film 152 may also be removed from the protective film-forming film 13 shown in Figure 1 and the second surface 13b of the protective film-forming film 13 may be attached to the back surface 9b of the wafer 9.

[0252] The protective film-forming film 13 can be attached to the wafer 9 by a known method. For example, the protective film-forming film 13 may be attached to the wafer 9 while being heated.

[0253] Next, in the curing step of manufacturing method 1, the protective film-forming film 13 in the first laminate film 601 is cured with energy rays to form a protective film 13', thereby producing a second laminate film 602 in which the protective film 13' and the wafer 9 are laminated in their thickness direction, as shown in Figure 6(b). Reference numeral 13a' denotes the surface of the protective film 13' that was the first surface 13a of the protective film-forming film 13 (sometimes referred to as the "first surface" in this specification). Reference numeral 13b' denotes the surface of the protective film 13' that was the second surface 13b of the protective film-forming film 13 (sometimes referred to as the "second surface" in this specification).

[0254] In the curing process, the protective film 13' is formed by irradiating the protective film forming film 13 with energy rays from the outside of the protective film forming film 13 side of the first laminated film 601 through the second peeling film 152 (transmitting through the second peeling film 152). In the curing process, the second release film 152 may be removed from the protective film-forming film 13 in the first laminated film 601 to expose the second surface 13b of the protective film-forming film 13, and then the protective film-forming film 13 may be irradiated with energy rays to form the protective film 13'.

[0255] The conditions for irradiation with energy rays in the curing step are as described above.

[0256] Laser marking may be performed by irradiating the protective film-forming film 13 shown in Figure 6(a) with a laser through the second release film 152 (through the second release film 152), or by irradiating the protective film 13' shown in Figure 6(b) with a laser through the second release film 152 (through the second release film 152).

[0257] Next, in the dividing step of manufacturing method 1, first, the second release film 152 is removed from the protective film 13' in the second laminate film 602. Then, one surface 8a (sometimes referred to as the "first surface" in this specification) of the dicing sheet 8 is attached to the newly exposed second surface 13b' of the protective film 13', as shown in FIG. 6(c). The dicing sheet 8 shown here is configured to include a base material 81 and an adhesive layer 82 provided on one surface 81a of the base material 81, and the adhesive layer 82 in the dicing sheet 8 is attached to the protective film 13'. The surface 82a of the adhesive layer 82 facing the protective film 13' (sometimes referred to as the "first surface" in this specification) is the same as the first surface 8a of the dicing sheet 8.

[0258] The dicing sheet 8 may be a known one. For example, the base material 81 may be the same as the base material in the composite sheet for forming a protective film described above, and the adhesive layer 82 may be the same as the adhesive layer in the composite sheet for forming a protective film described above.

[0259] Here, a case is shown in which a dicing sheet 8 having a base material 81 and an adhesive layer 82 is used, but in the dividing process, other dicing sheets may also be used, for example, a dicing sheet consisting of only a base material.

[0260] Next, in the dividing step, as shown in Fig. 6(d), with the dicing sheet 8 provided on the protective film 13' side of the second laminate film 602, the wafer 9 in the second laminate film 602 is divided and the protective film 13' is cut. The wafer 9 is divided into individual pieces into a plurality of chips 90.

[0261] Dividing the wafer 9 and cutting the protective film 13′ may be performed by a known method. For example, dividing the wafer 9 and cutting the protective film 13′ can be performed consecutively by dicing such as blade dicing, laser dicing using laser irradiation, or water dicing using water containing an abrasive. The protective film 13' is cut along the outer periphery of the chip 90 regardless of the cutting method.

[0262] In this way, by dividing the wafer 9 and cutting the protective film 13', a plurality of protective film-coated chips 901 are obtained, each chip including a chip 90 and a protective film (sometimes simply referred to as a "protective film" in this specification) 130' after cutting provided on the back surface 90b of the chip 90. Reference numeral 130b' denotes the surface of the protective film 130' after cutting that was the second surface 13b' of the protective film 13' (sometimes referred to as a "second surface" in this specification).

[0263] In the dividing step of manufacturing method 1, the third laminated film 603 is produced in such a manner that the plurality of chips 901 with protective film are fixed on the dicing sheet 8 as described above.

[0264] Next, in the pick-up step of manufacturing method 1, as shown in FIG. 6(e), the protective film-coated chip 901 in the third laminate film 603 is picked up by being pulled away from the dicing sheet 8. In the pick-up step, peeling occurs between the second surface 130b' of the protective film 130' in the protective film-coated chip 901 and the first surface 82a of the adhesive layer 82 in the dicing sheet 8.

[0265] Here, a case is shown in which a separating means 7 such as a vacuum collet is used to separate the protective film-coated chip 901 in the direction of arrow P. Note that a cross-sectional view of the separating means 7 is omitted here. The chip 901 with the protective film can be picked up by a known method.

[0266] If the adhesive layer 82 is energy ray-curable, it is preferable in the pick-up step to irradiate the adhesive layer 82 with energy rays to cure the adhesive layer 82 and form a cured product (not shown), and then peel the protective film-equipped chip 901 from the dicing sheet 8. In this case, in the pick-up step, peeling occurs between the protective film 130′ in the protective film-equipped chip 901 and the cured product of the adhesive layer 82 in the dicing sheet 8. In this case, the adhesive force between the cured adhesive layer 82 and the protective film 130' is weaker than the adhesive force between the adhesive layer 82 and the protective film 130', so that the chip 901 with the protective film can be picked up more easily.

[0267] The conditions for irradiating the pressure-sensitive adhesive layer 82 with energy rays in the pick-up step may be the same as the conditions for irradiating the protective film-forming film 13 with energy rays in the curing step, for example.

[0268] In this specification, even after the energy ray-curable pressure-sensitive adhesive layer is cured with energy rays, as long as the laminated structure of the substrate and the cured product of the energy ray-curable pressure-sensitive adhesive layer is maintained, this laminated structure is referred to as a "dicing sheet."

[0269] On the other hand, if the adhesive layer 82 is non-energy ray curable, the protective film-equipped chip 901 can be simply pulled away from the adhesive layer 82, and since there is no need to harden the adhesive layer 82, the protective film-equipped chip 901 can be picked up in a simplified process. Even if the adhesive layer 82 is energy ray curable, by picking up the protective film-attached chip 901 without curing the adhesive layer 82, the protective film-attached chip 901 can be picked up in a simplified process.

[0270] In the pick-up step, such pick-up of the protective film-coated chips 901 is carried out for all of the target protective film-coated chips 901 .

[0271] In manufacturing method 1, the desired chip 901 with a protective film is obtained by carrying out the steps up to the pick-up step.

[0272] In manufacturing method 1, the above-mentioned protective film-forming film is used, so that bleeding out of the surface of the protective film is suppressed in the reflow process when protective film-covered chip 901 is mounted on a circuit board. Therefore, if the protective film is laser-marked, deterioration of the laser mark can be suppressed even after the reflow process.

[0273] <<Manufacturing method 2>> 7 is a cross-sectional view for schematically explaining manufacturing method 2. Here, manufacturing method 2 will be explained using an example in which the composite sheet for forming a protective film 101 shown in FIG. 7(a), the protective film-forming film 13 in the protective film-forming composite sheet 101 is attached to the back surface 9b of the wafer 9 to produce a first laminated composite sheet 501 in which the support sheet 10, the protective film-forming film 13, and the wafer 9 are laminated in this order in the thickness direction. In this case, as in the case of manufacturing method 1, the first surface 13a of the protective film-forming film 13 in the protective film-forming composite sheet 101 is attached to the back surface 9b of the wafer 9.

[0274] The protective film-forming film 13 in the composite sheet 101 for forming a protective film can be attached to the wafer 9 by a known method. For example, the protective film-forming film 13 may be attached to the wafer 9 while being heated.

[0275] Next, in the curing step of manufacturing method 2, the protective film-forming film 13 in the first laminated composite sheet 501 is cured with energy rays to form a protective film 13', thereby producing a second laminated composite sheet 502 in which the support sheet 10, the protective film 13' and the wafer 9 are stacked in this order in the thickness direction, as shown in Figure 7(b).

[0276] In the curing process, a protective film 13' is formed by irradiating energy rays from the outside of the support sheet 10 side of the first laminated composite sheet 501 onto the protective film forming film 13 through the support sheet 10 (passing through the support sheet 10).

[0277] The curing step can be carried out in the same manner as the curing step in manufacturing method 1, except that the first laminated composite sheet 501 is used instead of the first laminated film 601.

[0278] The second laminated composite sheet 502 obtained in the curing step has the same structure as the laminate of the second laminate film 602 and the dicing sheet 8 in the dividing step in manufacturing method 1. When the dicing sheet 8 is the same as the support sheet 10, the second laminated composite sheet 502 is the same as the laminate.

[0279] Next, in the dividing step of manufacturing method 2, as shown in Fig. 7(c), wafer 9 in second laminated composite sheet 502 is divided and protective film 13' is cut. Wafer 9 is divided into individual pieces into a plurality of chips 90.

[0280] The dividing step can be carried out in the same manner as the dividing step in manufacturing method 1, except that a second laminated composite sheet 502 is used instead of the laminate of the second laminated film 602 and the dicing sheet 8. In manufacturing method 2, the protective film 13' is also cut along the outer periphery of the chip 90 regardless of the cutting method.

[0281] In this way, by dividing the wafer 9 and cutting the protective film 13', multiple chips 901 with protective film are obtained, each chip 90 having a protective film 130' after cutting provided on the back surface 90b of the chip 90. These protective film-attached chips 901 obtained in the dividing step in manufacturing method 2 are the same as the protective film-attached chips 901 obtained in the dividing step in manufacturing method 1.

[0282] The protective film-forming film 13 shown in Figure 7(a) may be laser-marked by irradiating it with a laser through the support sheet 10 (through the support sheet 10), or the protective film 13' shown in Figure 7(b) may be laser-marked by irradiating it with a laser through the support sheet 10 (through the support sheet 10).

[0283] In the dividing step of manufacturing method 2, third laminated composite sheet 503 is produced in which a plurality of chips 901 with protective film are fixed on support sheet 10 as described above. The third laminate composite sheet 503 has the same configuration as the third laminate film 603 obtained in the dividing step in manufacturing method 1. When the dicing sheet 8 is the same as the support sheet 10, the third laminate composite sheet 503 is the same as the third laminate film 603.

[0284] Next, in the pick-up step of manufacturing method 2, chip 901 with protective film in third laminated composite sheet 503 is picked up by being pulled away from support sheet 10, as shown in FIG. 7(d). In the pick-up step, peeling occurs between second surface 130b' of protective film 130' in protective film-coated chip 901 and first surface 12a of adhesive layer 12 in support sheet 10.

[0285] The pick-up step can be carried out in the same manner as the pick-up step in manufacturing method 1, except that third laminate composite sheet 503 is used instead of third laminate film 603.

[0286] For example, when the adhesive layer 12 is energy ray curable, it is preferable in the pickup step to irradiate the adhesive layer 12 with energy rays to cure the adhesive layer 12 and form a cured product (not shown), and then peel the protective film-equipped chip 901 from the support sheet 10. In this case, in the pickup step, peeling occurs between the protective film 130′ in the protective film-equipped chip 901 and the cured product of the adhesive layer 12 in the support sheet 10. In this case, the adhesive force between the cured adhesive layer 12 and the protective film 130' is weaker than the adhesive force between the adhesive layer 12 and the protective film 130', so that the chip 901 with the protective film can be picked up more easily.

[0287] On the other hand, if the adhesive layer 12 is non-energy ray curable, the protective film-equipped chip 901 can be simply pulled away from the adhesive layer 12, and since there is no need to harden the adhesive layer 12, the protective film-equipped chip 901 can be picked up in a simplified process. Even if the adhesive layer 12 is energy ray curable, by picking up the protective film-attached chip 901 without curing the adhesive layer 12, the protective film-attached chip 901 can be picked up in a simplified process.

[0288] In manufacturing method 2, the steps up to the pick-up step are carried out to obtain the desired chip with protective film 901. The chip with protective film 901 obtained by manufacturing method 2 is the same as the chip with protective film 901 obtained by manufacturing method 1.

[0289] In manufacturing method 2, the composite sheet for forming a protective film described above is used, so that bleeding out of the surface of the protective film is suppressed in the reflow process when mounting the protective film-coated chip 901 on a circuit board. Therefore, if the protective film is laser-marked, deterioration of the laser mark can be suppressed even after the reflow process.

[0290] So far, we have explained manufacturing method 2 when using composite sheet 101 for forming a protective film shown in Figure 2, but manufacturing method 2 may also use a composite sheet for forming a protective film of this embodiment other than composite sheet 101 for forming a protective film, such as composite sheet 102 for forming a protective film, composite sheet 103 for forming a protective film, or composite sheet 104 for forming a protective film shown in Figures 3 to 5.

[0291] ◇ Manufacturing method of substrate device (method of using chip with protective film) After the chip with a protective film is obtained by the above-described manufacturing method, a substrate device can be manufactured in the same manner as the conventional method for manufacturing a substrate device, except that this chip with a protective film is used instead of the conventional chip with a protective film.

[0292] For example, a method for manufacturing a substrate device includes a reflow process in which a circuit board mounted with a protective film-coated chip obtained using the protective film-forming film is heated using a reflow furnace equipped with a halogen heater, thereby melting the protruding electrodes on the protective film-coated chip, thereby strengthening the electrical connection between the protruding electrodes and the connection pads on the circuit board.

[0293] The substrate device of this embodiment uses the above-mentioned protective film-forming film or protective film-forming composite sheet, which suppresses bleeding out of the surface of the protective film during the reflow process. Therefore, the substrate device of this embodiment is superior to conventional substrate devices in that it has an excellent design of the protective film surface and suppresses deterioration of the laser mark. [Example]

[0294] The present invention will be described in more detail below with reference to specific examples, although the present invention is not limited to the examples shown below.

[0295] <Raw materials for resin production> The full names of the raw materials for producing the resins, which are abbreviated in the examples and comparative examples, are shown below. BA: n-butyl acrylate MA: methyl acrylate ACrMO: 4-acryloylmorpholine HEA: 2-hydroxyethyl acrylate 2EHMA: 2-ethylhexyl methacrylate

[0296] <Raw materials for producing the protective film-forming composition> The raw materials used in the production of the protective film-forming composition are shown below. [Energy ray curable component (a)] (a)-1: Urethane acrylate (KJ Chemicals "Quick cure 8100EA70") (a)-2: ε-caprolactone-modified tris-(2-acryloxyethyl) isocyanurate ("A-9300-1CL" manufactured by Shin-Nakamura Chemical Co., Ltd., a trifunctional UV-curable compound) [Acrylic resin (b) not having an energy ray-curable group] (b)-1: Acrylic resin (weight average molecular weight: 700,000, glass transition temperature: 2°C) which is a copolymer of BA (33 parts by mass), MA (27 parts by mass), ACrMO (25 parts by mass), and HEA (15 parts by mass). (b)-2: Acrylic resin (weight average molecular weight: 400,000, glass transition temperature: 6°C) which is a copolymer of MA (85 parts by mass) and HEA (15 parts by mass) [Photopolymerization initiator (c)] (c)-1: 2-(dimethylamino)-1-(4-morpholinophenyl)-2-benzyl-1-butanone (BASF "Omnirad (registered trademark) 369") (c)-2: 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropan-1-one (BASF "Omnirad (registered trademark) 127D") (c)-3: 2-hydroxy-2-methyl-1-phenylpropan-1-one (BASF "Omnirad (registered trademark) 1173") (c)-4: 1-Hydroxycyclohexyl-phenyl ketone (BASF "Omnirad (registered trademark) 184") [Inorganic filler (d)] (d)-1: Silica filler (fused silica filler, average particle size 8 μm) [Colorant (g)] (g)-1: Black pigment (a pigment obtained by mixing 32 parts by mass of a phthalocyanine blue pigment (Pigment Blue 15:3), 18 parts by mass of an isoindolinone yellow pigment (Pigment Yellow 139), and 50 parts by mass of an anthraquinone red pigment (Pigment Red 177), and pigmenting the mixture so that the total amount of the three pigments / the amount of styrene acrylic resin was 1 / 3 (mass ratio)). (g)-2: Organic black pigment (Dainichiseika Color & Chemicals Mfg. Co., Ltd. "6377 Black") [General-purpose additives (z)] (z)-1: Hydroxyphenyltriazine-based ultraviolet absorber (BASF "Tinuvin (registered trademark) 479")

[0297] <<Manufacturing protective film-forming films, composite sheets for protective film-forming, and chips with protective film>> [Example 1] <Production of protective film-forming composition (IV)-1> Energy ray-curable component (a)-1 (10.1 parts by mass), energy ray-curable component (a)-2 (12.4 parts by mass), acrylic resin (b)-1 (14.7 parts by mass) not having an energy ray-curable group, photopolymerization initiator (c)-1 (0.1 parts by mass), photopolymerization initiator (c)-2 (0.5 parts by mass), inorganic filler (d)-1 (58.4 parts by mass), colorant (g)-1 (3 parts by mass), and general-purpose additive (z)-1 (0.8 parts by mass) were dissolved or dispersed in methyl ethyl ketone and stirred at 23 ° C. to obtain an energy ray-curable protective film-forming composition (IV)-1, in which the total concentration of all components other than the solvent was 45% by mass. Note that the amounts of all components other than the solvent shown here are the amounts of the target product excluding the solvent.

[0298] <Production of protective film-forming film> A release film (second release film, "SP-PET382150" manufactured by Lintec Corporation, thickness 38 μm) made of polyethylene terephthalate film, one side of which had been treated for release by silicone treatment, was used, and the protective film-forming composition (IV)-1 obtained above was applied to the release-treated surface, followed by drying at 100°C for 2 minutes to produce an energy ray-curable protective film-forming film with a thickness of 25 μm.

[0299] Furthermore, by bonding the release-treated surface of a release film (first release film, "SP-PET381031" manufactured by Lintec Corporation, thickness 38 μm) to the exposed surface of the obtained protective film-forming film that did not have the second release film, a protective film-forming film with a release film was obtained, which was composed of a protective film-forming film, a first release film provided on one side of the protective film-forming film, and a second release film provided on the other side of the protective film-forming film.

[0300] <Production of Pressure-Sensitive Adhesive Composition (I-4)-1> A non-energy ray-curable pressure-sensitive adhesive composition (I-4)-1 was prepared containing an acrylic resin (100 parts by mass), a tolylene diisocyanate crosslinking agent (BHS8515 manufactured by Toyochem Co., Ltd.) (10.0 parts by mass as a crosslinking agent component), a hexamethylene diisocyanate crosslinking agent (Coronate HL manufactured by Tosoh Corporation) (7.5 parts by mass as a crosslinking agent component), and methyl ethyl ketone as a solvent. The acrylic resin was a copolymer with a weight-average molecular weight of 600,000, obtained by copolymerizing 2EHMA (80 parts by mass) and HEA (20 parts by mass).

[0301] <Manufacture of support sheet> A release film ("SP-PET381031" manufactured by Lintec Corporation, thickness 38 μm) made of polyethylene terephthalate, one side of which had been treated for release by silicone treatment, was used. The pressure-sensitive adhesive composition (I-4)-1 obtained above was applied to the release-treated surface, and the resulting film was dried by heating at 100°C for 2 minutes to form a non-energy ray-curable pressure-sensitive adhesive layer having a thickness of 5 μm. Next, a polypropylene film (80 μm thick, colorless) was attached to the exposed surface of the adhesive layer as a base material to produce a support sheet with a release film, which was composed of the base material, adhesive layer, and release film laminated in this order in the thickness direction.

[0302] <Production of composite sheet for forming protective film> The release film was removed from the support sheet obtained above. The second release film was also removed from the protective film-forming film obtained above. The exposed surface of the pressure-sensitive adhesive layer obtained by removing the release film was then bonded to the exposed surface of the protective film-forming film obtained by removing the second release film, thereby producing a composite sheet for forming a protective film, which was configured by laminating the substrate, pressure-sensitive adhesive layer, protective film-forming film, and first release film in this order in the thickness direction.

[0303] <Manufacturing chips with protective film> In the composite sheet for forming a protective film obtained above, the first release film was removed from the protective film-forming film. Then, using a tape laminating device ("Adwill RAD-2700" manufactured by Lintec Corporation), the newly exposed surface of this protective film-forming film was heat-laminated to the #2000 ground surface of a silicon wafer (thickness 300 μm) under conditions of lamination temperature 70°C, lamination pressure 0.3 MPa, and lamination speed 0.3 mm / s, thereby laminating the composite sheet for forming a protective film to the silicon wafer (lamination process). In this way, a first laminated composite sheet was produced.

[0304] Next, an ultraviolet irradiation device ("RAD2000m / 8" manufactured by Lintec Corporation) was used to irradiate the sample at an illuminance of 200 mW / cm 2 , light intensity 300mJ / cm 2 Under the conditions above, the protective film-forming film was irradiated twice with ultraviolet light through the substrate and the pressure-sensitive adhesive layer to harden the protective film-forming film and form a protective film (hardening step). In this way, a second laminated composite sheet was produced.

[0305] Next, the second laminated composite sheet was subjected to blade dicing using a dicing machine (DISCO Corporation, "DFD6362") to divide the silicon wafer into silicon chips measuring 3 mm x 3 mm, and the protective film was cut along the periphery of the silicon chip to produce multiple chips with protective film (dividing process). This produced a third laminated composite sheet consisting of multiple silicon chips with protective film fixed on a support sheet. These silicon chips with protective film were dried together with the sheet at 125°C for 24 hours.

[0306] Next, the silicon chip with the protective film in the third laminated composite sheet was picked up by separating it from the support sheet (pick-up step). In this way, the desired chip with a protective film was obtained.

[0307] [Example 2] <Production of protective film-forming composition (IV)-2> A protective film-forming composition (IV)-2 was produced in the same manner as the protective film-forming composition (IV)-1 in Example 1, except that the acrylic resin (b)-1 (14.7 parts by mass) not having an energy ray-curable group was replaced with the acrylic resin (b)-2 (14.7 parts by mass) not having an energy ray-curable group, the photopolymerization initiator (c)-1 (0.1 parts by mass) and the photopolymerization initiator (c)-2 (0.5 parts by mass) were replaced with the photopolymerization initiator (c)-3 (0.6 parts by mass), and the colorant (g)-1 (3 parts by mass) was replaced with the colorant (g)-2 (3 parts by mass).

[0308] <Production of protective film-forming film, composite sheet for protective film-forming, and chip with protective film> A protective film-forming film was produced in the same manner as in Example 1, except that the protective film-forming composition (IV)-2 was used instead of the protective film-forming composition (IV)-1. Then, a composite sheet for forming a protective film and a chip with a protective film were produced in the same manner as in Example 1, except that this protective film-forming film was used.

[0309] [Example 3] <Production of protective film-forming composition (IV)-3> A protective film-forming composition (IV)-3 was produced in the same manner as the protective film-forming composition (IV)-1 in Example 1, except that the amount of energy ray-curable component (a)-2 was changed from 12.4 parts by mass to 7.4 parts by mass, and the amount of acrylic resin (b)-1 not having an energy ray-curable group was changed from 14.7 parts by mass to 19.7 parts by mass.

[0310] <Production of protective film-forming film, composite sheet for protective film-forming, and chip with protective film> A protective film-forming film was produced in the same manner as in Example 1, except that the protective film-forming composition (IV)-3 was used instead of the protective film-forming composition (IV)-1. Then, a composite sheet for forming a protective film and a chip with a protective film were produced in the same manner as in Example 1, except that this protective film-forming film was used.

[0311] [Comparative Example 1] <Production of protective film-forming composition (X)-1> A protective film-forming composition (X)-1 was produced in the same manner as the protective film-forming composition (IV)-1 in Example 1, except that photopolymerization initiator (c)-4 (0.6 parts by mass) was used instead of photopolymerization initiator (c)-3 (0.6 parts by mass).

[0312] <Production of protective film-forming film, composite sheet for protective film-forming, and chip with protective film> A protective film-forming film was produced in the same manner as in Example 1, except that the protective film-forming composition (X)-1 was used instead of the protective film-forming composition (IV)-1. Then, a composite sheet for forming a protective film and a chip with a protective film were produced in the same manner as in Example 1, except that this protective film-forming film was used.

[0313] Comparative Example 2 <Production of protective film-forming composition (X)-2> A protective film-forming composition (X)-2 was prepared in the same manner as the protective film-forming composition (IV)-1 in Example 1, except that photopolymerization initiator (c)-3 (0.6 parts by mass) was replaced with photopolymerization initiator (c)-2 (0.6 parts by mass).

[0314] <Production of protective film-forming film, composite sheet for protective film-forming, and chip with protective film> A protective film-forming film was produced in the same manner as in Example 1, except that the protective film-forming composition (X)-2 was used instead of the protective film-forming composition (IV)-1. Then, a composite sheet for forming a protective film and a chip with a protective film were produced in the same manner as in Example 1, except that this protective film-forming film was used.

[0315] Comparative Example 3 <Production of protective film-forming composition (X)-3> A protective film-forming composition (X)-3 was produced in the same manner as the protective film-forming composition (IV)-1 in Example 1, except that the energy ray-curable component (a)-1 was not used, the amount of energy ray-curable component (a)-2 was changed from 12.4 parts by mass to 10.1 parts by mass, and the amount of acrylic resin (b)-1 not having an energy ray-curable group was changed from 14.7 parts by mass to 27.1 parts by mass.

[0316] <Production of protective film-forming film, composite sheet for protective film-forming, and chip with protective film> A protective film-forming film was produced in the same manner as in Example 1, except that the protective film-forming composition (X)-3 was used instead of the protective film-forming composition (IV)-1. Then, a composite sheet for forming a protective film and a chip with a protective film were produced in the same manner as in Example 1, except that this protective film-forming film was used.

[0317] <<Evaluation of protective film forming films>> <Measurement of storage modulus of protective film-forming film> For each example and comparative example, multiple protective film-forming films with release films obtained as described above were used, and the exposed surfaces of the protective film-forming films were bonded together while removing the first or second release film, to produce a test piece (protective film-forming film test piece) (thickness 200 μm, length 30 mm in the tensile direction in the tensile mode) which was a laminate of multiple protective film-forming films. Next, using an automatic dynamic viscoelasticity measuring device (A&D Corporation's "Leovibron DDV-01FP"), the storage modulus E' of the protective film-formed film specimen was measured in the temperature range from -10°C to 140°C under the measurement conditions of tensile method (tensile mode), chuck distance 20 mm, amplitude 5 μm, frequency 11 Hz, heating rate 3°C / min, and constant heating rate.

[0318] <Measurement of storage modulus of protective film> For each example and comparative example, a laminate (50 μm thick) of multiple protective film-forming films was produced by using multiple protective film-forming films with release films obtained as described above and bonding the exposed surfaces of the protective film-forming films together while removing the first or second release film. Next, the laminate was irradiated from both sides with ultraviolet light ("RAD2000m / 8" manufactured by Lintec Corporation) at an illuminance of 200 mW / cm. 2 , light intensity 300mJ / cm 2 The protective film-forming film was cured to form a protective film by irradiating it twice with ultraviolet light having a wavelength of 365 nm under the conditions of

[0043] . After obtaining a laminate of multiple protective films in this manner, the width of the laminate was adjusted to 5 mm to prepare a test piece (protective film test piece) (thickness 50 μm). Next, using a dynamic mechanical analyzer (TA Instruments, "DMA Q800"), the storage modulus E' of the protective film specimen was measured in the temperature range from 0°C to 300°C under the following measurement conditions: tension method (tensile mode), chuck distance 20 mm, amplitude 5 μm, frequency 11 Hz, heating rate 3°C / min, and constant heating rate.

[0319] <Measurement of weight loss rate ΔW1 (%) after heat treatment at 130℃ for 2 hours> For the protective film-forming films of Examples 1 to 3 and Comparative Examples 1 to 3, test pieces of approximately 10 mg were heated from 25°C to 130°C at a heating rate of 10°C / min using a Shimadzu Corporation TG / DTA simultaneous measurement device DTG-60, and then further heated at 130°C for 2 hours. The weight loss rate (ΔW1) (wt%) was calculated from the weight of the protective film-forming film before heating (W0) and the weight of the protective film-forming film after heating (W1) using the following formula (1). The results are shown in Tables 1 and 2. ΔW1=(W0-W1) / W0×100 (1)

[0320] <Measurement of weight loss rate ΔW2 (%) after two UV irradiations> For the protective film-forming films of Examples 1 to 3 and Comparative Examples 1 to 3, a 150 mm x 150 mm test piece was exposed to an illuminance of 200 mW / cm using a UV irradiation device RAD2000 manufactured by Lintec Corporation. 2 , light intensity 300mJ / cm 2 The protective film-forming film was irradiated with ultraviolet light twice under the conditions above. The weight loss rate (ΔW2) (wt%) was calculated from the weight (W0) of the protective film-forming film before ultraviolet light irradiation and the weight (W2) of the protective film-forming film after heating using the following formula (2). The results are shown in Tables 1 and 2. ΔW2=(W0-W2) / W0×100 (2)

[0321] <Measurement of weight loss ΔW3 (%) after UV irradiation twice and heat treatment at 260℃ for 10 minutes> For the protective film-forming films of Examples 1 to 3 and Comparative Examples 1 to 3, a 150 mm x 150 mm test piece was exposed to an illuminance of 200 mW / cm using a UV irradiation device RAD2000 manufactured by Lintec Corporation. 2 , light intensity 300mJ / cm 2The film was irradiated with ultraviolet light twice under the above conditions. Furthermore, using a Shimadzu DTG-60 TG / DTA simultaneous measurement system, the film was heated from 25°C to 260°C at a rate of 10°C / min, and then heated at 260°C for 10 minutes. The weight loss rate (ΔW3) (wt%) was calculated from the weight of the protective film-formed film before ultraviolet irradiation (W0) and the weight of the protective film after heating (W3) using the following formula (3). The results are shown in Tables 1 and 2. ΔW3=(W0-W3) / W0×100 (3)

[0322] <Measurement of gel fraction of components other than inorganic fillers> The protective film-forming films of Examples 1 to 3 and Comparative Examples 1 to 3 were exposed to UV irradiation at an illuminance of 200 mW / cm using a RAD2000 UV irradiation device manufactured by Lintec Corporation. 2 , light intensity 300mJ / cm 2 Under the conditions above, the sample was irradiated twice with ultraviolet light having a wavelength of 365 nm. Next, the protective film-forming film after ultraviolet irradiation was cut into a size of 50 mm × 100 mm to prepare a sample, which was then wrapped in a 100 mm × 150 mm nylon mesh sheet (mesh size 200) and stapled to prepare a test piece. The mass M1 of the test piece, the mass M2 of the nylon mesh sheet, and the mass M3 of the staples were weighed using a precision balance. In addition, the protective film-forming film was previously baked at 600°C for 30 minutes, and the mass of the inorganic component in the mass M1 of the test piece was calculated from the mass of the residue.It was confirmed that the mass of this inorganic component was equal to the mass M4 of the inorganic filler (d) in the formulation of the protective film-forming films of Examples 1 to 3 and Comparative Examples 1 to 3.

[0323] The test piece was then immersed in ethyl acetate (100 mL) at 25°C for 48 hours. The insoluble portion of the protective film after UV irradiation, the nylon mesh sheet, and the staples were then removed and dried at 90°C for 3 hours. The test piece was then left at 23°C and 50% relative humidity for 1 hour to condition the humidity. The mass M5 of the test piece after immersion and drying was then weighed using a precision balance. The gel fraction of the components other than the inorganic filler was then calculated using the following formula (4). The results are shown in Tables 1 and 2. ΔG=(M5-M2-M3-M4) / (M1-M2-M3-M4)×100 (4)

[0324] <Measurement of the rate of decline in gross value> The support sheet was peeled off from each of the second laminated composite sheets obtained from the protective film-forming films of Examples 1 to 3 and Comparative Examples 1 to 3 to prepare test specimens. The gloss value of the exposed protective film surface (gloss value (G1) of the protective film after energy ray curing) was measured using a gloss meter (VG7000 manufactured by Nippon Denshoku Industries Co., Ltd.) at an incident angle of 60°. Each test piece was then heated at 260°C for 10 minutes. The gloss value of the protective film surface (gloss value (G2) of the protective film after 10 minutes of heat treatment) was then measured under the same conditions as for the gloss value (G1) before heating. The gloss value reduction rate (%) was calculated using the following formula (5): Gloss value decrease rate (%) = (G1 - G2) / G1 × 100 (5) The gloss value before heating (G1), the gloss value after heating (G2), and the reduction rate (%) of the gloss value are shown in Tables 1 and 2.

[0325] Furthermore, visual observation showed that the gloss value tended to decrease as the amount of bleed-out on the surface of the protective film increased. Therefore, films with a gloss value decrease rate of less than 30% were evaluated as having little bleed-out on the surface of the protective film (A), and films with a gloss value decrease rate of 30% or more were evaluated as having much bleed-out on the surface of the protective film (C), and these results are shown in Tables 1 and 2.

[0326] [Table 1]

[0327] [Table 2]

[0328] As is clear from the above results, the protective film-forming films of Examples 1 to 3 contain an energy ray-curable component (a), and after being energy ray-cured and heat-treated at 260°C for 10 minutes, the weight loss rate is 3.0% or less, and the gel fraction of the components other than the inorganic filler after being energy ray-cured is 60% or more. As a result, there is little decrease in gloss value when heat-treated at 260°C for 10 minutes, which is a general condition for the reflow process, and the protective film formed by curing the protective film-forming film with energy rays is suppressed from bleeding out during the reflow process.

[0329] The storage modulus E' of the protective film-forming film test piece at 70°C 70 The values ​​were 1.0 MPa (Example 1), 1.0 MPa (Example 2), and 0.9 MPa (Example 3), all of which had favorable properties for attachment to a wafer.

[0330] Storage modulus E' of the protective film test piece at 130°C 130 The values ​​were 50 MPa (Example 1), 40 MPa (Example 2), and 25 MPa (Example 3), all of which had favorable properties as a protective film.

[0331] In contrast, the protective film-forming films of Comparative Examples 1 to 3 had weight loss rates of more than 3.0% after being energy ray-cured and heat-treated at 260°C for 10 minutes, and the gel fraction of components other than the inorganic filler after being energy ray-cured was less than 60%. The protective film-forming films of Comparative Examples 1 to 3 had a large decrease in gloss value after being heat-treated at 260°C for 10 minutes, which is a general condition for the reflow process, and there is concern about bleed-out of the protective film formed by curing the protective film-forming film with energy rays during the reflow process. [Industrial Applicability]

[0332] The present invention can be used in the manufacture of various substrate devices, including semiconductor devices. [Explanation of symbols]

[0333] 10, 20... support sheet, 10a, 20a... one side (first side) of the support sheet, 11...Base material, 12...adhesive layer, 13, 23... Energy ray curable protective film-forming film, 13'... Protective film, 13b'... Other surface (second surface) of the protective film, 130'... Protective film after cutting, 101, 102, 103, 104...Composite sheet for forming protective film, 501...first laminated composite sheet, 502...second laminated composite sheet, 503...third laminated composite sheet, 601...first laminate film, 602...second laminate film, 603...third laminate film, 8...Dicing sheet, 9...wafer, 9b...backside of wafer, 90...chip, 90b...backside of chip, 901...chip with protective film

Claims

1. An energy ray-curable protective film-forming film, The protective film-forming film contains an energy ray-curable component (a), an acrylic resin (b) having no energy ray-curable group, and a photopolymerization initiator (c), the photopolymerization initiator (c) contains only 2-hydroxy-2-methyl-1-phenylpropan-1-one, or 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropan-1-one, or 1-hydroxycyclohexyl-phenyl ketone and 2-(dimethylamino)-1-(4-morpholinophenyl)-2-benzyl-1-butanone; The content ratio of the energy ray-curable component (a) is 12 to 31 mass% with respect to the total mass of the protective film-forming film, the content ratio of the acrylic resin (b) not having an energy ray-curable group is 8 to 27 mass% with respect to the total mass of the protective film-forming film, Illuminance of the protective film-forming film: 200 mW / cm ２ , light intensity 300mJ / cm ２ the protective film-forming film is energy ray-cured by irradiating it twice with ultraviolet light having a wavelength of 365 nm under the conditions of, and then heating it from 25°C to 260°C at a temperature increase rate of 10°C / min, and further heat-treated at 260°C for 10 minutes, and the weight loss rate of the protective film-forming film after heating relative to the protective film before energy ray curing is 3.0% or less, Illuminance of the protective film-forming film: 200 mW / cm ２ , light intensity 300mJ / cm ２ The protective film-forming film has a gel fraction of 60% or more of components other than the inorganic filler after the protective film-forming film is energy ray-cured by irradiating it twice with ultraviolet light having a wavelength of 365 nm under the conditions of

2. Illuminance of the protective film-forming film: 200 mW / cm ２ , light intensity 300mJ / cm ２ The protective film-forming film is irradiated twice with ultraviolet light having a wavelength of 365 nm under the conditions of an illuminance of 200 mW / cm with respect to the gloss value (G1) of the protective film after the protective film-forming film is energy ray-cured. ２ , light intensity 300mJ / cm ２ The protective film-forming film according to claim 1, wherein the protective film-forming film is energy ray-cured by irradiating it twice with ultraviolet light having a wavelength of 365 nm under the conditions of (a) and (b) above, and the gloss value (G2) of the protective film after being heat-treated at 260°C for 10 minutes is reduced by 30% or less.

3. A protective film-forming film as described in claim 1 or 2, wherein the energy ray curable component (a) contains a multifunctional urethane (meth)acrylate oligomer.

4. A support sheet and a protective film-forming film provided on one surface of the support sheet, A composite sheet for forming a protective film, wherein the protective film-forming film is the protective film-forming film according to any one of claims 1 to 3.

5. A method for manufacturing a chip with a protective film, the method comprising: The method for manufacturing the chip with a protective film includes the steps of: attaching the protective film-forming film according to any one of claims 1 to 3 to the rear surface of a wafer to produce a first laminated film in which the protective film-forming film and the wafer are laminated in their thickness direction; or attaching the protective film-forming film in the composite sheet for forming a protective film according to claim 4 to the rear surface of a wafer to produce a first laminated composite sheet in which the support sheet, the protective film-forming film, and the wafer are laminated in this order in their thickness direction; a step of forming the protective film by energy ray curing the protective film-forming film in the first laminate film or the first laminate composite sheet to produce a second laminate film in which the protective film and the wafer are laminated in their thickness direction, or a step of producing a second laminate composite sheet in which the support sheet, the protective film, and the wafer are laminated in this order in their thickness direction; a step of dividing the wafer in the second laminate film and cutting the protective film while a dicing sheet is provided on the protective film side of the second laminate film, thereby producing a third laminate film configured such that a plurality of the protective film-equipped chips are fixed on the dicing sheet, or dividing the wafer in the second laminate composite sheet and cutting the protective film, thereby producing a third laminate composite sheet configured such that a plurality of the protective film-equipped chips are fixed on the support sheet; A method for manufacturing a chip with a protective film, comprising a step of picking up the chip with a protective film in the third laminate film by separating it from the dicing sheet, or by separating the chip with a protective film in the third laminate composite sheet by separating it from the support sheet.

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