Thermosetting resin film and first protective film forming sheet

Abstract

The thermosetting resin film of the present embodiment is a thermosetting resin film for forming a first protective film on a surface of a workpiece having a convex electrode by being attached to the surface and thermally cured. The thermosetting resin film contains two or more thermosetting components other than an acrylic resin having an epoxy group. The total content of all types of the thermosetting components in the thermosetting resin film is 40% by mass or more relative to the total mass of the thermosetting resin film. When the X value is obtained for each type of the thermosetting components contained in the thermosetting resin film and the total value of the X values ​​of all types of the thermosetting components is obtained, the total value is 400 g / eq or less.

Description

Technical Field

[0001] The present invention relates to a thermosetting resin film and a sheet for forming a first protective film.

[0002] This application claims priority based on Japanese Patent Application No. 2019-032828 filed in Japan on February 26, 2019, and uses the contents thereof herein. Background Art

[0003] Until now, a flip chip mounting method has been used to mount a multi-pin LSI package for an MPU or gate array on a printed wiring board. In this mounting method, a workpiece (e.g., a semiconductor wafer) having convex electrodes (e.g., bumps, small columns, etc.) is used, and the convex electrodes in the workpiece (e.g., a semiconductor chip as a semiconductor wafer segment) are brought into contact with corresponding terminal portions on the substrate by a so-called flip-chip method to achieve melt / diffusion connection.

[0004] When this mounting method is used, a curable resin film is sometimes attached to the surface of the protruding electrode and the circuit surface of the workpiece for the purpose of protecting the circuit surface and the protruding electrode of the workpiece, and the film is cured to form a protective film on these surfaces.

[0005] In addition, in this specification, the combination of the surface of the convex electrode and the circuit surface of the workpiece or the workpiece processed product may be referred to as a "convex electrode forming surface".

[0006] The curable resin film is usually attached to the convex electrode forming surface of the workpiece in a heated and softened state. As a result, the upper part of the convex electrode including the top passes through the curable resin film and protrudes from the curable resin film. On the other hand, the curable resin film spreads between the convex electrodes in a manner covering the convex electrodes of the workpiece, closely adheres to the circuit surface, and at the same time covers the surface of the convex electrodes, especially the surface of the part near the circuit surface, thereby burying the convex electrodes. Then, by further curing the curable resin film, the circuit surface of the workpiece and the surface of the part near the circuit surface of the convex electrode are further covered, forming a protective film to protect these areas.

[0007] When a semiconductor wafer is used, the semiconductor chips used in the mounting method can be obtained by, for example, grinding the surface of the semiconductor wafer having protruding electrodes formed on the circuit surface opposite to the circuit surface, and dicing and dividing the surface.

[0008] In such a process of obtaining a semiconductor wafer, a curable resin film is usually attached to the surface where the protruding electrodes are formed in order to protect the circuit surface and the protruding electrodes of the semiconductor wafer, and the film is cured to form a protective film on the surface where the protruding electrodes are formed.

[0009] Furthermore, the semiconductor wafer is divided into semiconductor chips, and finally semiconductor chips having a protective film on the surface on which the bump electrodes are formed (sometimes referred to as "semiconductor chips with protective film" in this specification) are formed (see Patent Document 1).

[0010] The workpiece having a protective film on the convex electrode forming surface (sometimes referred to as a "workpiece with a protective film" in this specification) is further mounted on a substrate to form a package, and the package is further used to form a target device. When a semiconductor chip with a protective film is mounted on a substrate, the semiconductor package thus obtained can be used to form a target semiconductor device.

[0011] Prior art literature

[0012] Patent Literature

[0013] Patent Document 1: Japanese Patent No. 5515811 Summary of the invention

[0014] Technical Problems to be Solved by the Invention

[0015] When using a conventional curable resin film, for example, the method disclosed in Patent Document 1, the workpiece is usually divided by blade cutting using a dicing blade (for example, dividing a semiconductor wafer into semiconductor chips). However, although this method is the most popular, it is not suitable for manufacturing small-sized workpieces or thin workpieces. This is because such workpieces are prone to cracks or defects.

[0016] Therefore, the object of the present invention is to provide a resin film that can form a protective film for protecting a convex electrode forming surface of a workpiece or a workpiece, and by using the resin film, a new method for dividing a workpiece can be suitably used. In particular, it is an object to provide a resin film that can suppress residue on the upper part of the convex electrode when attached to the convex electrode forming surface when the new method is applied, and can well cut the protective film as a cured product when dividing the workpiece.

[0017] Technical means to solve technical problems

[0018] The present invention provides a thermosetting resin film, which is a thermosetting resin film for forming a first protective film on a surface of a workpiece having a convex electrode by being attached to the surface and thermally cured, wherein the thermosetting resin film contains two or more thermosetting components other than an acrylic resin having an epoxy group, the total content of all types of the thermosetting components in the thermosetting resin film is 40% by mass or more relative to the total mass of the thermosetting resin film, and when an X value calculated by the following formula is obtained for each type of the thermosetting components contained in the thermosetting resin film, and the total value of the X values ​​of all types of the thermosetting components contained in the thermosetting resin film is obtained, the total value is 400 g / eq or less.

[0019] X = [equivalent weight of functional groups of the thermosetting component that participate in the thermosetting reaction (g / eq)] × [content of the thermosetting component in the thermosetting resin film (parts by mass)] / [total content of all types of thermosetting components in the thermosetting resin film (parts by mass)]

[0020] Furthermore, the present invention provides a first protective film forming sheet including a first supporting sheet, wherein the first supporting sheet includes the thermosetting resin film on one surface thereof.

[0021] Effects of the Invention

[0022] According to the present invention, a resin film can be provided that can form a protective film for protecting a convex electrode forming surface of a workpiece or a workpiece processed object, and a new method for dividing a workpiece can be suitably used by using the resin film. In particular, a resin film can be provided that can suppress residue on the upper part of the convex electrode when attached to the convex electrode forming surface under the application of the new method, and can well cut the protective film as a cured product when dividing the workpiece. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a cross-sectional view schematically showing an example of a state in which a first protective film is formed on a convex electrode formation surface using a curable resin film according to an embodiment of the present invention.

[0024] Figure 2 It is a cross-sectional view schematically showing an example of the first protective film forming sheet according to one embodiment of the present invention.

[0025] Figure 3 It is a cross-sectional view schematically showing another example of the first protective film forming sheet according to one embodiment of the present invention.

[0026] Figure 4 This is a cross-sectional view schematically showing still another example of the first protective film-forming sheet according to one embodiment of the present invention.

[0027] Figure 5A This is an enlarged cross-sectional view for schematically illustrating a method for producing a workpiece having a first protective film when a sheet for forming a first protective film according to one embodiment of the present invention is used.

[0028] Figure 5B This is an enlarged cross-sectional view for schematically illustrating a method for producing a workpiece having a first protective film when a sheet for forming a first protective film according to one embodiment of the present invention is used.

[0029] Figure 5C This is an enlarged cross-sectional view for schematically illustrating a method for producing a workpiece having a first protective film when a sheet for forming a first protective film according to one embodiment of the present invention is used.

[0030] Fig. 6A This is an enlarged cross-sectional view for schematically illustrating a method for producing a workpiece having a first protective film when a sheet for forming a first protective film according to one embodiment of the present invention is used.

[0031] Figure 6B This is an enlarged cross-sectional view for schematically illustrating a method for producing a workpiece having a first protective film when a sheet for forming a first protective film according to one embodiment of the present invention is used. DETAILED DESCRIPTION

[0032] ◇Thermosetting resin film, first protective film forming sheet

[0033] A thermosetting resin film according to one embodiment of the present invention is a thermosetting resin film for forming a first protective film on a surface of a workpiece having a convex electrode (i.e., a convex electrode forming surface) by being attached to the surface and thermally cured, wherein the thermosetting resin film contains two or more thermosetting components other than an acrylic resin having an epoxy group, the total content of all types of the thermosetting components in the thermosetting resin film is 40% by mass or more relative to the total mass of the thermosetting resin film, and when an X value calculated by the following formula is obtained for each type of the thermosetting components contained in the thermosetting resin film and the total value of the X values ​​of all types of the thermosetting components contained in the thermosetting resin film is obtained, the total value is 400 g / eq or less.

[0034] X = [equivalent weight of functional groups of the thermosetting component that participate in the thermosetting reaction (g / eq)] × [content of the thermosetting component of the thermosetting resin film (parts by mass)] / [total content of all types of thermosetting components of the thermosetting resin film (parts by mass)]

[0035] In one embodiment of the present invention, the first protective film forming sheet includes a first support sheet, and the thermosetting resin film is provided on one surface of the first support sheet. In the first protective film forming sheet, the "thermosetting resin film" is sometimes referred to as a "thermosetting resin layer".

[0036] In the present embodiment, as the workpiece, for example, a semiconductor wafer or the like can be cited.

[0037] Examples of the workpiece include semiconductor chips that are divided products of a semiconductor wafer.

[0038] The processing of the workpiece includes, for example, segmentation.

[0039] Examples of the convex electrode include bumps, pillars, etc. The convex electrode is provided on a connection pad portion of a workpiece and is made of eutectic solder, high-temperature solder, gold, copper, or the like.

[0040] The first protective film forming sheet is used by attaching the convex electrode forming surface of the workpiece (i.e., the surface of the convex electrode and the circuit surface of the workpiece) via its thermosetting resin film (thermosetting resin layer). In addition, the fluidity of the attached thermosetting resin film increases due to heating, and the upper part of the convex electrode including the top passes through the thermosetting resin film and protrudes from the thermosetting resin film. Furthermore, the thermosetting resin film spreads between the convex electrodes in a manner covering the convex electrodes, closely fitting the circuit surface, and at the same time covers the surface of the convex electrodes, especially the surface of the part near the circuit surface, and buries the convex electrodes. The thermosetting resin film in this state is further cured by heating, and finally forms a first protective film, which protects the circuit surface and the convex electrode in a state of being closely fitted to the circuit surface and the convex electrode. Therefore, by using the thermosetting resin film of this embodiment, the circuit surface of the workpiece and the part near the circuit surface of the convex electrode, i.e., the base, can be fully protected by the first protective film.

[0041] For the workpiece to which the first protective film forming sheet is attached, for example, the surface opposite to the circuit surface can be ground as needed, and then the first support sheet can be removed, and then the convex electrode is buried and the first protective film is formed by heating the thermosetting resin film. Further, the workpiece is divided (i.e., singulated into workpieces) and the first protective film is cut, and by using the workpieces obtained in this way with the cut first protective film on the convex electrode forming surface (sometimes referred to as "workpieces with the first protective film"), a target substrate device such as a semiconductor device can be manufactured. These processes will be described in detail later.

[0042] In addition, in this specification, unless otherwise specified, the description of "curable resin film" means "curable resin film before curing", and the description of "curable resin layer" means "curable resin layer before curing". For example, "thermosetting resin film" means "thermosetting resin film before curing", and "first protective film" means a cured product of thermosetting resin film.

[0043] The thermosetting resin film of the present embodiment is suitable for a method different from the conventional method as a method of dividing (in other words, singulating) a workpiece into processed workpieces. Here, examples of the “method different from the conventional method” include the following methods.

[0044] That is, by irradiating a workpiece having a first protective film formed of the thermosetting resin film on a convex electrode forming surface with a laser, a modified layer is formed inside the workpiece. Then, a force is applied to the workpiece after the modified layer is formed. More specifically, in this embodiment, the workpiece is extended in a direction parallel to the circuit surface of the workpiece. Thus, the workpiece is divided at the position of the modified layer. At this time, by also applying a force to the first protective film, more specifically, by extending the first protective film in a direction parallel to the surface of the first protective film attached to the workpiece, the first protective film can also be cut at the same time. At this time, the first protective film is cut along the dividing position of the workpiece. In the above manner, a workpiece with a first protective film having a workpiece and a cut first protective film formed on the convex electrode forming surface of the workpiece can be manufactured. When manufacturing such a workpiece, since the first protective film is a cured product of the thermosetting resin film, the workpiece can be well divided into the workpiece. In addition, since the first protective film itself is a cured product of the thermosetting resin film, it can be easily cut along the dividing position of the workpiece when the workpiece is divided.

[0045] This method of dividing a workpiece with formation of a reformed layer is called stealth cutting (registered trademark), and is fundamentally different from laser cutting in which a workpiece is irradiated with laser light to cut off the workpiece surface while scraping off the irradiated portion of the workpiece.

[0046] <<Ratio of the total content of all types of thermosetting components>>

[0047] In the thermosetting resin film, the "thermosetting component" that specifies the above-mentioned total content ratio refers to a component that exhibits a curing reaction by heating. Among them, acrylic resin having an epoxy group is not included in the thermosetting component. As a thermosetting component, for example, the thermosetting component (B) described later can be listed.

[0048] Examples of the thermosetting component (B) include epoxy thermosetting resins, polyimide resins, unsaturated polyester resins, etc. The epoxy thermosetting resin is composed of an epoxy resin (B1) and a thermosetting agent (B2), and both components are subject to the above-mentioned total content ratio.

[0049] On the other hand, examples of acrylic resins having epoxy groups that are not included in the thermosetting component include acrylic resins having epoxy groups in the acrylic resins in the polymer component (A) described below. For example, acrylic resins having glycidyl groups are included in acrylic resins having epoxy groups.

[0050] The thermosetting resin film may contain two or more thermosetting components, and the combination and ratio thereof may be arbitrarily selected.

[0051] As described above, the ratio of the total content of all kinds of the thermosetting components in the thermosetting resin film to the total mass of the thermosetting resin film ([total content of all kinds of thermosetting components in the thermosetting resin film (parts by mass)] / [total mass of the thermosetting resin film (parts by mass)]×100) is 40% by mass or more. Here, the total content (parts by mass) of all kinds of thermosetting components refers to the total content (parts by mass) of all kinds of thermosetting components of two or more kinds.

[0052] By satisfying the condition of the ratio of the total content, when the thermosetting resin film is attached to the convex electrode forming surface of the workpiece, it is possible to suppress the thermosetting resin film from remaining on the upper part of the convex electrode including the top, and it has suitable characteristics for a resin film used to form a first protective film. In this way, when the thermosetting resin film is attached to the convex electrode forming surface, by preventing the thermosetting resin film from remaining on the upper part of the convex electrode, in other words, by making the upper part of the convex electrode penetrate the attached thermosetting resin film and protrude, the final workpiece processed object can be fully electrically connected to the substrate through its convex electrode during flip-chip mounting. That is, if the thermosetting resin film cannot be suppressed from remaining on the upper part of the convex electrode, the workpiece processed object cannot be used for practical applications.

[0053] In order to more significantly obtain the above-mentioned beneficial effects, the ratio of the total content of all types of the thermosetting components in the thermosetting resin film to the total mass of the thermosetting resin film can be, for example, any value of 50 mass %, 60 mass %, 70 mass % or more and 80 mass % or more.

[0054] The upper limit of the total content ratio is not particularly limited. For example, in order to further improve the film-forming properties of the thermosetting resin film, the total content ratio is preferably 90% by mass or less.

[0055] The ratio of the total content can be appropriately adjusted within a range set by arbitrarily combining the above lower limit value and upper limit value. For example, in one embodiment, the ratio of the total content can be any range among 40 to 90% by mass, 50 to 90% by mass, 60 to 90% by mass, 70 to 90% by mass, and 80 to 90% by mass.

[0056] <<Total value of X value>>

[0057] For one thermosetting component contained in the thermosetting resin film, the X value is calculated by the above formula.

[0058] The "thermosetting component" that is the calculation object of the X value is the same as the "thermosetting component" that defines the ratio of the total content in the thermosetting resin film.

[0059] The "functional group participating in the thermosetting reaction of the thermosetting component" for calculating the X value refers to, for example, in the case of the epoxy resin (B1) described later, it is an epoxy group, and in the case of the thermosetting agent (B2) described later, it is a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group, a group formed by acid anhydride of an acid group, etc. Among them, these groups are only an example of the functional group.

[0060] Consider the case where the thermosetting resin film contains p kinds (p is an integer of 2 or more) of thermosetting components. These thermosetting components are designated as M1, M P . And, the equivalent weight of the functional group of the thermosetting component M1 is set as m1 (g / eq), and the equivalent weight of the functional group of the thermosetting component M p is set as m p (g / eq), the content of the thermosetting component M1 in the thermosetting resin film is set as C1 (parts by mass), and the content of the thermosetting component M p in the thermosetting resin film is set as C p (parts by mass).

[0061] At this time, for the thermosetting component M1, the X value (hereinafter referred to as "X1 value") can be calculated by the following formula:

[0062] [Mathematical formula 1]

[0063]

[0064] Similarly, for the thermosetting component M p , the X value (hereinafter referred to as "X p value") can be calculated by the following formula:

[0065] [Mathematical formula 2]

[0066]

[0067] Furthermore, all types of thermosetting components (M1, ..., M p ) of the X values ​​(X1, ..., X p ) are as follows.

[0068] [Mathematical formula 3]

[0069]

[0070] The equivalent weight (m1, m p When (g / eq)) is not limited to a constant value but is limited to a numerical range having a width, the average value calculated from the lower limit value and the upper limit value of the numerical range may be used as the equivalent weight of the functional group.

[0071] In the thermosetting resin film, the total value of the X value is 400 g / eq or less.

[0072] By satisfying the condition of the total value of the X value, the first protective film, which is a cured product of the thermosetting resin film, can be easily cut when the workpiece is divided. As a result, a workpiece having the cut first protective film on the convex electrode forming surface can be efficiently manufactured.

[0073] In order to more significantly obtain the above advantageous effects, in the thermosetting resin film, the total value of the X value may be, for example, 375 g / eq or less, 350 g / eq or less, or 325 g / eq or less.

[0074] The lower limit of the total value of the X value is not particularly limited. For example, in order to suppress a decrease in flexibility due to an excessive crosslinking reaction, the total value of the X value in the thermosetting resin film is preferably 100 g / eq or more.

[0075] The total value of the X value can be appropriately adjusted within the range set by any combination of the above lower limit and upper limit. For example, in one embodiment, the total value of the X value can be any range of 100 to 400 g / eq, 100 to 375 g / eq, 100 to 350 g / eq, and 100 to 325 g / eq.

[0076] <<Light transmittance of thermosetting resin film>>

[0077] The light transmittance of a layer of the thermosetting resin film with a thickness of 200 μm at a wavelength of 1342 nm is preferably 50% or more.

[0078] Furthermore, the light transmittance at a wavelength of 1342 nm of a laminated film having a total thickness of 200 μm formed by laminating two or more thermosetting resin films having a thickness of less than 200 μm is preferably 50% or more.

[0079] As a method for splitting a workpiece to produce a workpiece processed product, when the method described above is applied with the formation of a modified layer inside the workpiece, the modified layer can be formed by irradiating the workpiece with a laser having a wavelength of 1342 nm. At this time, the laser can be irradiated from the circuit surface side of the workpiece, or from the back side of the workpiece. When the laser is irradiated from the circuit surface side of the workpiece, the laser is irradiated through the first protective film formed on the circuit surface.

[0080] On the other hand, the transmittance of the same wavelength of the thermosetting resin film and its cured product (such as the first protective film) is almost the same or completely the same. Therefore, when the transmittance of a layer of the thermosetting resin film with a thickness of 200μm at a wavelength of 1342nm is 50% or more, the transmittance of its cured product at a wavelength of 1342nm is also 50% or more. Similarly, when the transmittance of the laminated film at a wavelength of 1342nm is 50% or more, the transmittance of its cured product at a wavelength of 1342nm is also 50% or more. That is, the first protective film formed using a thermosetting resin film of the same composition as the thermosetting resin film that satisfies such a transmittance condition can well transmit laser light of a wavelength of 1342nm. Therefore, a workpiece having such a first protective film on the circuit surface is suitable as a workpiece that is irradiated with laser light from its circuit surface side to form a modified layer inside the workpiece.

[0081] In order to make the above effects more significant, the transmittance at a wavelength of 1342 nm of a layer of thermosetting resin film with a thickness of 200 μm or a stacked film with a total thickness of 200 μm can be, for example, any value above 60%, above 70%, above 80% and above 85%.

[0082] The upper limit of the transmittance at a wavelength of 1342 nm of a single layer of thermosetting resin film with a thickness of 200 μm or a laminated film with a total thickness of 200 μm is not particularly limited, and the higher the transmittance, the better. For example, in terms of the ease of manufacturing thermosetting resin films, the transmittance is preferably 95% or less.

[0083] The light transmittance can be appropriately adjusted within a range set by any combination of the above lower limit and upper limit. In one embodiment, the light transmittance is preferably 50-95%, for example, it can also be any range of 60-95%, 70-95%, 80-95% and 85-95%.

[0084] For a layer of thermosetting resin film with a thickness of 200 μm and the laminated film with a total thickness of 200 μm, as long as they contain the same components, their (a layer of thermosetting resin film and the laminated film) transmittances are the same, and are not limited to the case where the wavelength of light is 1342 nm.

[0085] The number of layers of the thermosetting resin film having a thickness of less than 200 μm constituting the laminated film is not particularly limited, but is preferably 2 to 6. With such a number of layers, the laminated film can be produced more easily.

[0086] The thicknesses of the thermosetting resin films having a thickness of less than 200 μm constituting the laminated film may all be the same, all be different, or partly be the same.

[0087] In the present embodiment, the thickness of the layer of the thermosetting resin film or laminated film to be measured for the light transmittance is set to 200 μm because the light transmittance can be measured more accurately and easily by using a thermosetting resin film or laminated film of such a thickness.

[0088] In the present embodiment, the thickness of a single-layer thermosetting resin film and a thermosetting resin film composed of two or more layers is not limited to 200 μm as described later.

[0089] For example, the light transmittance can be adjusted by adjusting the types and contents of components contained in the thermosetting resin film such as the colorant (I) and the filler (D) described later, and the surface state of the thermosetting resin film.

[0090] <<Breaking Strength of First Protective Film>>

[0091] The first protective film having a size of 20 mm×130 mm and a thickness of 40 μm preferably has a breaking strength of 55 MPa or less as measured by the following method. A first protective film having the same composition as the first protective film having a breaking strength below the upper limit is easier to cut by expansion described below.

[0092] The breaking strength of the first protective film can be measured by setting the distance between the clamps in the first protective film to 80 mm, setting the stretching speed of the first protective film to 200 mm / min, and measuring the maximum stress when the first protective film is stretched in a direction parallel to the surface of the first protective film using the clamps.

[0093] As the first protective film to be measured for the maximum stress, a protective film obtained by heat-curing a thermosetting resin film at 130° C. for 2 hours can be used.

[0094] In order to make the above-mentioned effect more remarkable, the breaking strength of the first protective film may be, for example, any one of 52.5 MPa or less, 50 MPa or less, and 47.5 MPa or less.

[0095] The lower limit of the breaking strength of the first protective film is not particularly limited. In order to enhance the protective function of the first protective film, the breaking strength of the first protective film is preferably 0.1 MPa or more.

[0096] The breaking strength of the first protective film can be appropriately adjusted within the range set by any combination of the above lower limit and upper limit. In one embodiment, the breaking strength of the first protective film is preferably 0.1 to 55 MPa, for example, it can also be any range of 0.1 to 52.5 MPa, 0.1 to 50 MPa and 0.1 to 47.5 MPa.

[0097] For example, the breaking strength of the first protective film can be adjusted by adjusting the components contained in the thermosetting resin layer forming composition described later, especially the types and contents of the polymer component (A), coupling agent (E), filler (D), etc., and the thickness of the first protective film (in other words, the thickness of the thermosetting resin film).

[0098] In a workpiece or workpiece processed object having a convex electrode on the circuit surface, the surface (back surface) opposite to the circuit surface is sometimes exposed. Therefore, a protective film containing an organic material is sometimes formed on the back surface (in this specification, it is sometimes referred to as a second protective film to distinguish it from the first protective film). The second protective film is used to prevent cracks from being generated in the workpiece processed object after the workpiece is divided or packaged. Such a workpiece processed object with a second protective film having a second protective film on the back surface is finally assembled into a target substrate device such as a semiconductor device.

[0099] On the other hand, sometimes the second protective film is required to have information related to the workpiece processing object that can be marked with a laser, or to cover the back of the workpiece processing object. As a protective film that fully meets this requirement, it is known that there is a curable resin film that can form the second protective film by curing and adjusts the light transmittance.

[0100] However, the second protective film for protecting the back side of the workpiece and the first protective film for protecting the convex electrode forming surface of the workpiece are formed at different positions on the workpiece, and therefore the properties sought are also different from each other. Therefore, it is usually difficult to directly use the thermosetting resin film that can form the second protective film for the formation of the first protective film.

[0101] Figure 1 This is a cross-sectional view schematically showing an example of a state in which a first protective film is formed on a convex electrode forming surface using a thermosetting resin film of the present embodiment. In addition, in order to facilitate understanding of the features of the present invention, for convenience, important parts of the figures used in the following description are sometimes enlarged and displayed, and the size ratios of the various components are not necessarily the same as the actual situation.

[0102] A plurality of convex electrodes 91 are provided on the circuit surface 90a of the workpiece 90 shown here. Figure 1 In the figure, reference numeral 90b indicates the surface (back surface) of the workpiece 90 which is opposite to the circuit surface 90a.

[0103] The convex electrode 91 has a shape obtained by cutting a part of a sphere with a plane, and a plane of the convex electrode 91 corresponding to a portion exposed by the cutout is in contact with the circuit surface 90 a of the workpiece 90 .

[0104] The shape of the convex electrode 91 is approximately spherical.

[0105] The first protective film 12' is a protective film formed using the thermosetting resin film of the present embodiment, and covers the circuit surface 90a of the workpiece 90, and further covers the surface 91a of the convex electrode 91 except for the top 910 and the vicinity of the top of the convex electrode 91. Thus, the first protective film 12' is in close contact with the surface 91a of the convex electrode 91 except for the top 910 and the vicinity of the top, and is also in close contact with the circuit surface 90a of the workpiece 90, filling the convex electrode 91.

[0106] The above-described substantially spherical shape of the protruding electrode 91 is particularly advantageous for forming the first protective film using the curable resin film.

[0107] The height H of the protruding electrode 91 91 The height H of the protruding electrode 91 is not particularly limited, but is preferably 50 to 500 μm. 91 The function of the convex electrode 91 can be further improved by setting the height H of the convex electrode 91 to be equal to or greater than the lower limit. 91 Below the upper limit value, when a thermosetting resin film is attached to the convex electrode forming surface of the workpiece 90 (i.e., the surface 91a of the convex electrode 91 and the circuit surface 90a of the workpiece 90), the effect of suppressing the thermosetting resin film from remaining on the upper part of the convex electrode 91 including the top 910 is further increased, and as a result, the effect of suppressing the formation of the first protective film 12' on the upper part of the convex electrode 91 is further increased.

[0108] In this specification, the "height of the convex electrode" refers to the height from the circuit surface of the workpiece or the workpiece to the highest position (ie, the top) of the convex electrode.

[0109] The width W of the protruding electrode 91 91 The width W of the protruding electrode 91 is not particularly limited, but is preferably 50 to 600 μm. 91 The function of the convex electrode 91 can be further improved by setting the width W of the convex electrode 91 to be equal to or greater than the lower limit. 91 Below the upper limit value, when a thermosetting resin film is attached to the convex electrode forming surface of the workpiece 90 (i.e., the surface 91a of the convex electrode 91 and the circuit surface 90a of the workpiece 90), the effect of suppressing the thermosetting resin film from remaining on the upper part of the convex electrode 91 including the top 910 is further increased, and as a result, the effect of suppressing the formation of the first protective film 12' on the upper part of the convex electrode 91 is further increased.

[0110] In this specification, the “width of the protruding electrode” refers to the maximum value of a line segment connecting two different points on the surface of the protruding electrode with a straight line when the protruding electrode is viewed downward from a direction perpendicular to the circuit surface of the workpiece or the workpiece processed product.

[0111] The distance D between adjacent protruding electrodes 91 91 The distance D between the protruding electrodes 91 is not particularly limited, but is preferably 100 to 800 μm. 91 When the distance D between the convex electrodes 91 is greater than the lower limit, when the thermosetting resin film is attached to the convex electrode forming surface of the workpiece 90 (i.e., the surface 91a of the convex electrode 91 and the circuit surface 90a of the workpiece 90), the effect of suppressing the thermosetting resin film from remaining on the upper part including the top 910 of the convex electrode 91 is further increased, and as a result, the effect of suppressing the formation of the first protective film 12' on the upper part of the convex electrode 91 is further increased. 91 When the value is equal to or less than the upper limit, the degree of freedom in the arrangement of the protruding electrodes 91 becomes higher.

[0112] In addition, in this specification, "the distance between adjacent protruding electrodes" refers to the minimum value of the distance between the surfaces of adjacent protruding electrodes.

[0113] The thickness T of the workpiece 90 except for the convex electrode 91 90 The method may be appropriately selected according to the purpose of use of the workpiece 90 and is not particularly limited.

[0114] For example, the thickness T after grinding the back surface 90 b of the workpiece 90 is 90 The thickness T of the workpiece 90 after the back surface 90 b is ground is preferably 50 to 500 μm. 90 When the workpiece 90 is divided (in other words, it is singulated into individual workpieces), the effect of suppressing the damage of the workpiece is further improved. 90 When the value is equal to or less than the above upper limit, a thin workpiece can be obtained.

[0115] The thickness T before grinding the back surface 90b of the workpiece 90 90 It is preferably 250 to 1500 μm.

[0116] The workpiece to which the thermosetting resin film of this embodiment is applied is not limited to Figure 1 The workpieces shown may be partially changed, deleted or added without impairing the effects of the present invention.

[0117] For example, in Figure 1In the embodiment, the convex electrode is shown as an electrode having the above-mentioned approximately spherical shape (a shape obtained by cutting a part of a sphere in a plane), but as a preferred shape of the convex electrode, there can also be listed: such an approximately spherical shape is convexly arranged in the height direction (in Figure 1 The convex electrode is a convex electrode having a shape formed by stretching the convex electrode in the direction perpendicular to the circuit surface 90a of the workpiece 90 (in other words, a shape formed by cutting out a portion of the spheroid as a prolate ellipsoid including one end in the long axis direction with a plane), or a convex electrode having a shape formed by extruding the above-mentioned approximately spherical shape in the height direction, that is, a shape formed by extruding a portion of the spheroid as a prolate ellipsoid including one end in the short axis direction with a plane. Such a convex electrode having a shape approximately similar to a spherical convex electrode is also particularly advantageous for forming the first protective film using the thermosetting resin film of this embodiment.

[0118] As convex electrodes, in addition to the above-mentioned electrodes, for example, there can be listed cylindrical, elliptical cylindrical, prism, elliptical cone, pyramid, truncated cone, elliptical cone or truncated pyramid electrodes, and electrodes having a shape formed by a combination of a cylinder, elliptical cylindrical, prism, truncated cone, elliptical cone or truncated pyramid with the above-mentioned approximate sphere or approximate rotational ellipsoid.

[0119] The shape of the protruding electrodes described above is merely an example preferred when the thermosetting resin film of the present embodiment is applied, and in the present invention, the shape of the protruding electrodes is not limited thereto.

[0120] Hereinafter, the configuration of the present invention will be described in detail.

[0121] ◎First support sheet

[0122] The first support sheet may be composed of one layer (single layer) or more than two layers. When the support sheet is composed of multiple layers, the constituent materials and thicknesses of these multiple layers may be the same or different from each other, and the combination of these multiple layers is not particularly limited as long as the effect of the present invention is not impaired.

[0123] In addition, in this specification, not limited to the first supporting sheet, "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 may be different from each other" means "at least one of the constituent materials and thicknesses of each layer is different from each other".

[0124] Preferred first support sheets include, for example, a first support sheet comprising a first substrate and a first adhesive layer disposed on the first substrate (in other words, a first support sheet formed by stacking the first substrate and the first adhesive layer along their thickness direction); a first support sheet comprising a first substrate, a first intermediate layer disposed on the first substrate, and a first adhesive layer disposed on the first intermediate layer (in other words, a first support sheet formed by stacking the first substrate, the first intermediate layer and the first adhesive layer in sequence along their thickness direction); a first support sheet consisting only of the first substrate, etc.

[0125] Hereinafter, examples of the first protective film forming sheet according to the present embodiment will be described according to the types of the above-mentioned first supporting sheet with reference to the drawings.

[0126] Figure 2 It is a cross-sectional view schematically showing an example of the first protective film forming sheet according to the present embodiment.

[0127] The first protective film forming sheet 1 shown here uses a sheet formed by stacking a first substrate and a first adhesive layer in their thickness direction as a first supporting sheet. That is, the first protective film forming sheet 1 is composed of a first substrate 11, a first adhesive layer 13 provided on one surface of the first substrate 11, and a thermosetting resin layer (thermosetting resin film) 12 provided on a surface 13a of the first adhesive layer 13 opposite to the first substrate 11 side.

[0128] The first support sheet 101 is a laminate of the first substrate 11 and the first adhesive layer 13. The first protective film forming sheet 1 can be said to be a sheet including the first support sheet 101 and the thermosetting resin layer 12 provided on one surface 101a of the first support sheet 101, in other words, provided on one surface 13a of the first adhesive layer 13.

[0129] In the thermosetting resin layer 12 in the first protective film-forming sheet 1 , the total content of the thermosetting components is 40% by mass or more, and the total value of the X value is 400 g / eq or less.

[0130] Figure 3 It is a cross-sectional view schematically showing another example of the first protective film-forming sheet according to the present embodiment.

[0131] In addition, Figure 3 In the subsequent drawings, the same components as those shown in the drawings that have already been described are denoted by the same reference numerals as those in the drawings that have already been described, and detailed description thereof will be omitted.

[0132] The first protective film forming sheet 2 shown here uses a sheet formed by stacking the first substrate, the first intermediate layer and the first adhesive layer in order in the thickness direction thereof as the first supporting sheet. That is, the first protective film forming sheet 2 is composed of a first substrate 11, a first intermediate layer 14 provided on one surface of the first substrate 11, a first adhesive layer 13 provided on the surface of the first intermediate layer 14 opposite to the first substrate 11 side, and a thermosetting resin layer (thermosetting resin film) 12 provided on the surface 13a of the first adhesive layer 13 opposite to the first intermediate layer 14 side.

[0133] The first support sheet 102 is a laminate of the first substrate 11, the first intermediate layer 14, and the first adhesive layer 13. It can be said that the first protective film forming sheet 2 includes the first support sheet 102 and includes the thermosetting resin layer 12 on one surface 102a of the first support sheet 102, in other words, on one surface 13a of the first adhesive layer 13.

[0134] In other words, the first protective film forming sheet 2 Figure 2 The first protective film-forming sheet 1 shown further includes a first intermediate layer 14 between the first base material 11 and the first adhesive layer 13 .

[0135] In the thermosetting resin layer 12 in the first protective film-forming sheet 2 , the total content of the thermosetting components is 40% by mass or more, and the total value of the X value is 400 g / eq or less.

[0136] Figure 4 It is a cross-sectional view schematically showing still another example of the first protective film-forming sheet according to the present embodiment.

[0137] The first protective film forming sheet 3 shown here uses a sheet composed only of the first base material as the first support sheet. That is, the first protective film forming sheet 3 is composed of the first base material 11 and the thermosetting resin layer (thermosetting resin film) 12 provided on the first base material 11.

[0138] The first support sheet 103 is composed only of the first substrate 11. The first protective film-forming sheet 3 includes the first support sheet 103 and the thermosetting resin layer 12 on one surface 103a of the first support sheet 103, in other words, on one surface 11a of the first substrate 11.

[0139] In other words, the first protective film forming sheet 3 is omitted. Figure 2 The first adhesive layer 13 in the first protective film-forming sheet 1 is shown.

[0140] In the thermosetting resin layer 12 in the first protective film-forming sheet 3 , the total content of the thermosetting components is 40% by mass or more, and the total value of the X value is 400 g / eq or less.

[0141] Next, the structure of the first supporting sheet will be described.

[0142] In the present embodiment, as the first supporting sheet, a well-known supporting sheet can be used, and the first supporting sheet can be appropriately selected according to the purpose.

[0143] ○First substrate

[0144] The first substrate is in a sheet or film shape, and examples of its constituent material include various resins.

[0145] The resin constituting the first substrate may be only one type or two or more types. When there are two or more types, the combination and ratio thereof may be arbitrarily selected.

[0146] The first substrate may be a single layer (single layer) or may be a plurality of layers of two or more. When the first substrate is a plurality of layers, the plurality of layers may be the same as or different from each other, and the combination of the plurality of layers is not particularly limited.

[0147] The thickness of the first substrate is preferably 50 to 200 μm.

[0148] Here, the “thickness of the first substrate” refers to the thickness of the entire substrate. For example, the thickness of the first substrate composed of a plurality of layers refers to the total thickness of all the layers constituting the first substrate.

[0149] In addition to the above-mentioned main constituent materials such as the resin, the first base material may contain various known additives such as a filler, a colorant, an antistatic agent, an antioxidant, an organic lubricant, a catalyst, and a softener (plasticizer).

[0150] The first substrate may be transparent or opaque, may be colored according to the purpose, and may have other layers deposited thereon.

[0151] When the first adhesive layer or the thermosetting resin layer described later has energy ray curability, the first substrate preferably transmits energy rays.

[0152] For example, as described in the examples below, the first substrate may be a release film obtained by subjecting one side of a resin film to a release treatment such as silicone treatment.

[0153] The first substrate can be produced by a known method. For example, the first substrate containing a resin can be produced by molding a resin composition containing the resin.

[0154] ○First adhesive layer

[0155] The first adhesive layer is in a sheet or film shape and contains an adhesive.

[0156] Examples of the adhesive include adhesive resins such as acrylic resin, urethane resin, rubber resin, silicone resin, epoxy resin, polyvinyl ether, and polycarbonate, and acrylic resin is preferred.

[0157] In addition, in the present invention, "adhesive resin" is a concept that includes both resins having adhesive properties and resins having adhesive properties. For example, it includes not only resins that have adhesive properties themselves, but also resins that exhibit adhesive properties by being used simultaneously with other components such as additives, or resins that exhibit adhesive properties due to the presence of triggers such as heat or water.

[0158] The first adhesive layer may be only one layer (single layer) or may be two or more layers. When it is a plurality of layers, the plurality of layers may be the same as or different from each other, and the combination of the plurality of layers is not particularly limited.

[0159] The thickness of the first adhesive layer is preferably 3 to 40 μm.

[0160] Here, “the thickness of the first adhesive layer” refers to the thickness of the entire first adhesive layer. For example, the thickness of the first adhesive layer composed of a plurality of layers refers to the total thickness of all the layers constituting the first adhesive layer.

[0161] The first adhesive layer may be formed using an energy-ray-curable adhesive or a non-energy-ray-curable adhesive. The first adhesive layer formed using an energy-ray-curable adhesive can easily adjust the physical properties before and after curing.

[0162] In this specification, "energy rays" refer to rays having energy quanta among electromagnetic waves or charged particle beams, and examples thereof include ultraviolet rays, radiation, electron beams, and the like.

[0163] For example, ultraviolet rays can be irradiated by using a high pressure mercury lamp, a fusion lamp, a xenon lamp, a black light lamp, an LED lamp, etc. as an ultraviolet light source. The electron beam can be irradiated with an electron beam generated by an electron beam accelerator, etc.

[0164] In the present 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 by irradiation with energy rays.

[0165] <First Adhesive Composition>

[0166] The first adhesive layer can be formed using a first adhesive composition containing an adhesive. For example, the first adhesive composition can be applied to the surface of the object on which the first adhesive layer is to be formed, and dried as needed to form the first adhesive layer at the target site. A more specific method for forming the first adhesive layer will be described in detail later together with the method for forming other layers.

[0167] The first adhesive composition can be applied by a known method, for example, methods using various coaters such as an air knife coater, a blade coater, a rod coater, a gravure coater, a roll coater, a roll knife coater, a curtain coater, a die coater, a blade coater, a screen coater, a Meyer rod coater, and a kiss coater.

[0168] The drying conditions of the first adhesive composition are not particularly limited, but when the first adhesive composition contains a solvent, it is preferably dried by heating. The first adhesive composition containing a solvent is preferably dried at 70 to 130° C. for 10 seconds to 5 minutes, for example.

[0169] When the first adhesive layer is energy-ray-curable, the first adhesive composition containing an energy-ray-curable adhesive, that is, the energy-ray-curable first adhesive composition, can include, for example, a first 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; a first adhesive composition (I-2) containing an energy-ray-curable adhesive resin (I-2a) (hereinafter, sometimes abbreviated as "adhesive resin (I-2a)") having an unsaturated group introduced into the side chain of the adhesive resin (I-1a); a first adhesive composition (I-3) containing the adhesive resin (I-2a) and an energy-ray-curable low molecular weight compound, etc.

[0170] <First Adhesive Composition Other Than First Adhesive Compositions (I-1) to (I-3)>

[0171] The components contained in the first adhesive composition (I-1), the first adhesive composition (I-2) or the first adhesive composition (I-3) can also be used in all first adhesive compositions other than these three first adhesive compositions (referred to as "first adhesive compositions other than the first adhesive compositions (I-1) to (I-3)" in this specification).

[0172] As the first adhesive composition other than the adhesive compositions (I-1) to (I-3), in addition to energy-ray-curable adhesive compositions, non-energy-ray-curable adhesive compositions can be mentioned.

[0173] As an example of the non-energy ray-curable first adhesive composition, there can be mentioned a first adhesive composition (I-4) containing the above-mentioned adhesive resin (I-1a).

[0174] The first adhesive composition (I-4) preferably contains an acrylic resin as the adhesive resin (I-1a), and more preferably further contains one or two or more cross-linking agents.

[0175] <Method for preparing the first adhesive composition>

[0176] The first adhesive composition (I-1) to (I-4) and the like can be obtained by blending the components constituting the first adhesive composition, that is, by blending the adhesive and, if necessary, components other than the adhesive.

[0177] The order of adding the components when blending them is not particularly limited, and two or more components may be added simultaneously.

[0178] When a solvent is used, the solvent may be mixed with any blending components other than the solvent to dilute the blending components in advance and then used, or the solvent may be mixed with the blending components without diluting the blending components in advance and then used.

[0179] The method for mixing the components during blending is not particularly limited, and may be appropriately selected from the following known methods: a method of mixing by rotating a stirring bar or a stirring blade, a method of mixing by using a mixer, a method of mixing by applying ultrasonic waves, and the like.

[0180] The temperature and time for adding and mixing the components are not particularly limited as long as the components do not deteriorate, and may be appropriately adjusted. However, the temperature is preferably 15 to 30°C.

[0181] ○First middle layer

[0182] The first intermediate layer is in a sheet or film shape, and its constituent material may be appropriately selected according to the purpose and is not particularly limited.

[0183] For example, when the purpose is to suppress deformation of the first protective film caused by the first protective film provided on the convex electrode forming surface reflecting the shape of the convex electrode existing on the circuit surface, from the perspective of further improving the adhesion of the first intermediate layer, preferred constituent materials of the first intermediate layer include urethane (meth) acrylate and the like.

[0184] The first intermediate layer may be only one layer (single layer) or may be two or more layers. When the first intermediate layer is a plurality of layers, the plurality of layers may be the same as or different from each other, and the combination of the plurality of layers is not particularly limited.

[0185] The thickness of the first intermediate layer can be appropriately adjusted according to the height of the protruding electrodes on the surface of the workpiece or workpiece to be protected. For example, the thickness of the first intermediate layer is preferably 50 to 600 μm in order to easily offset the influence of the high protruding electrodes.

[0186] Here, “the thickness of the first intermediate layer” refers to the thickness of the entire first intermediate layer. For example, the thickness of the first intermediate layer composed of a plurality of layers refers to the total thickness of all the layers constituting the first intermediate layer.

[0187] <<First Intermediate Layer Forming Composition>>

[0188] The first intermediate layer can be formed using a first intermediate layer forming composition containing its constituent materials. For example, the first intermediate layer forming composition is applied to the target surface where the first intermediate layer is to be formed, and dried as needed, or cured by irradiating energy rays, thereby forming the first intermediate layer at the target site. A more specific method for forming the first intermediate layer will be described in detail later together with the method for forming other layers.

[0189] For example, the first intermediate layer forming composition can be applied by the same method as in the case of the first adhesive composition.

[0190] The drying conditions of the first intermediate layer forming composition are not particularly limited, and may be, for example, the same as the drying conditions of the first adhesive composition.

[0191] When the composition for forming the first intermediate layer has energy ray curability, it can be cured by further irradiating the composition with energy rays after drying.

[0192] <Method for preparing the first intermediate layer forming composition>

[0193] For example, the first intermediate layer forming composition can be prepared by the same method as the first adhesive composition except that the blended components are different.

[0194] ◎Thermosetting resin film (thermosetting resin layer)

[0195] The thermosetting resin film (thermosetting resin layer) is a film (layer) for protecting the circuit surface of the workpiece and the workpiece processed object, and the protruding electrodes provided on the circuit surface.

[0196] The thermosetting resin film forms a first protective film by thermal curing.

[0197] In addition, in this specification, as long as the stacked structure of the first support sheet and the cured product of the thermosetting resin film (in other words, the first support sheet and the first protective film) can be maintained, the stacked structure will be referred to as a "sheet for forming the first protective film" even after the thermosetting resin film is cured (in other words, after the first protective film is formed).

[0198] The thermosetting resin film may or may not have energy ray-curable properties in addition to thermosetting properties.

[0199] When the thermosetting resin film has energy ray curing properties, it is assumed that the contribution of thermal curing of the thermosetting resin film to the first protective film formed of the thermosetting resin film is greater than the contribution of energy ray curing.

[0200] Regardless of whether it has energy ray curability, the thermosetting resin film can be composed of one layer (single layer) or more than two layers. When the thermosetting resin film is composed of multiple layers, these multiple layers can be the same or different from each other, and the combination of these multiple layers is not particularly limited.

[0201] Regardless of whether it is energy-ray curable or not, the thickness of the thermosetting resin film is preferably 1 to 100 μm, more preferably 3 to 80 μm, and particularly preferably 5 to 60 μm. By making the thickness of the thermosetting resin film above the lower limit, a first protective film with higher protective performance can be formed. By making the thickness of the thermosetting resin film below the upper limit, when the thermosetting resin film is attached to the convex electrode forming surface of the workpiece, the effect of suppressing the thermosetting resin film from remaining on the upper part of the convex electrode is further increased. In addition, by making the thickness of the thermosetting resin film below the upper limit, the first protective film can be cut better when the workpiece is divided.

[0202] Here, “the thickness of the thermosetting resin film” refers to the thickness of the entire thermosetting resin film. For example, the thickness of a thermosetting resin film composed of a plurality of layers refers to the total thickness of all the layers constituting the thermosetting resin film.

[0203] <<Thermosetting resin layer forming composition>>

[0204] The thermosetting resin film can be formed using a thermosetting resin layer-forming composition containing its constituent materials. For example, the thermosetting resin film can be formed by applying the thermosetting resin layer-forming composition on the surface of the object on which the thermosetting resin film is to be formed and drying it as needed. The content ratio of the components that do not vaporize at room temperature in the thermosetting resin layer-forming composition is usually the same as the content ratio of the components of the thermosetting resin film.

[0205] The coating of the composition for forming a thermosetting resin layer can be carried out using a known method, for example, a method using various coaters such as an air knife coater, a blade coater, a rod coater, a gravure coater, a roll coater, a roll knife coater, a curtain coater, a die coater, a blade coater, a screen coater, a Meyer rod coater, and a kiss coater.

[0206] Regardless of whether the thermosetting resin film has energy-ray curing properties, the drying conditions of the composition for forming a thermosetting resin layer are not particularly limited. However, when the composition for forming a thermosetting resin layer contains a solvent described later, it is preferably dried by heating. The composition for forming a thermosetting resin layer containing a solvent can be dried, for example, at 70 to 130° C. for 10 seconds to 5 minutes. Among them, it is preferred to heat and dry the composition for forming a thermosetting resin layer in a manner that does not thermally cure the composition itself and the thermosetting resin film formed by the composition.

[0207] The curing conditions when the thermosetting resin film is thermally cured to form the first protective film are not particularly limited as long as the first protective film has a degree of curing to a degree that allows the first protective film to fully exhibit its function, and may be appropriately selected depending on the type of the thermosetting resin film.

[0208] For example, the heating temperature during thermal curing of the thermosetting resin film is preferably 100 to 200° C., more preferably 110 to 180° C., and particularly preferably 120 to 170° C. Furthermore, the heating time during thermal curing is preferably 0.5 to 5 hours, more preferably 0.5 to 4 hours, and particularly preferably 1 to 3 hours.

[0209] As a preferred thermosetting resin film, for example, a resin film containing a polymer component (A) and a thermosetting component (B) can be cited. The polymer component (A) can be regarded as a component formed by a polymerization reaction of a polymerizable compound. In addition, the thermosetting component (B) is a component that can undergo a curing (polymerization) reaction using heat as an inducement for the reaction. In addition, in this specification, the polymerization reaction also includes a polycondensation reaction.

[0210] <Thermosetting Resin Layer-Forming Composition (III-1)>

[0211] Preferred examples of the thermosetting resin layer-forming composition include a thermosetting resin layer-forming composition (III-1) (sometimes simply abbreviated as “composition (III-1)” in this specification) containing the polymer component (A) and the thermosetting component (B).

[0212] [Polymer component (A)]

[0213] The polymer component (A) is a polymer compound for imparting film-forming properties, flexibility, etc. to the thermosetting resin film. The polymer component (A) has thermoplasticity but does not have thermosetting properties.

[0214] The polymer component (A) contained in the composition (III-1) and the thermosetting resin film may be one kind or two or more kinds. When there are two or more kinds, the combination and ratio thereof may be arbitrarily selected.

[0215] Examples of the polymer component (A) include acrylic resins, urethane resins, phenoxy resins, silicone resins, and saturated polyester resins.

[0216] Among them, the polymer component (A) is preferably polyvinyl acetal or acrylic resin.

[0217] Examples of the polyvinyl acetal in the polymer component (A) include known compounds.

[0218] Among these, examples of preferred polyvinyl acetals include polyvinyl formal and polyvinyl butyral, and polyvinyl butyral is more preferred.

[0219] Examples of the polyvinyl butyral include polyvinyl butyrals having structural units represented by the following formulae (i)-1, (i)-2, and (i)-3.

[0220] [Chemical formula 1]

[0221]

[0222] In the formula, l, m and n are each independently an integer of 1 or more.

[0223] The weight average molecular weight (Mw) of polyvinyl acetal is preferably 5000 to 200000, more preferably 8000 to 100000. When the weight average molecular weight of polyvinyl acetal is within this range, the effect of suppressing the thermosetting resin film from remaining on the upper part of the protruding electrode when the thermosetting resin film is attached to the protruding electrode forming surface is further improved.

[0224] The glass transition temperature (Tg) of polyvinyl acetal is preferably 40 to 80° C., more preferably 50 to 70° C. When the Tg of polyvinyl acetal is within this range, the effect of suppressing the thermosetting resin film from remaining on the upper part of the protruding electrode when the thermosetting resin film is attached to the protruding electrode forming surface is further improved.

[0225] The ratio of three or more monomers constituting polyvinyl acetal can be arbitrarily selected.

[0226] The acrylic resin in the polymer component (A) refers to a resin having a structural unit derived from (meth)acrylic acid or a derivative thereof.

[0227] In addition, in this specification, "(meth)acrylic acid" is a concept including both "acrylic acid" and "methacrylic acid". The same applies to terms similar to (meth)acrylic acid, for example, "(meth)acryloyl" is a concept including both "acryloyl" and "methacryloyl", and "(meth)acrylate" is a concept including both "acrylate" and "methacrylate".

[0228] In this specification, a "derivative" of a specific compound refers to a compound having a structure in which one or more hydrogen atoms in the compound are replaced by a group (substituent) other than a hydrogen atom. For example, (meth)acrylate is a derivative of (meth)acrylic acid.

[0229] Examples of the acrylic resin in the polymer component (A) include known acrylic polymers.

[0230] The weight average molecular weight (Mw) of the acrylic resin is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1,500,000. By making the weight average molecular weight of the acrylic resin above the lower limit, the shape stability (time stability during storage) of the thermosetting resin film is improved. By making the weight average molecular weight of the acrylic resin below the upper limit, the thermosetting resin film easily follows the concavoconvex surface of the adherend, and the generation of gaps between the adherend and the thermosetting resin film can be further suppressed.

[0231] In addition, in this specification, unless otherwise specified, "weight average molecular weight" means a polystyrene conversion value measured by gel permeation chromatography (GPC) method.

[0232] The glass transition temperature (Tg) of the acrylic resin is preferably -60 to 70°C, more preferably -30 to 50°C. By making the Tg of the acrylic resin above the lower limit, for example, the adhesive force between the cured product of the thermosetting resin film and the support sheet can be suppressed, and the peelability of the support sheet can be appropriately improved. By making the Tg of the acrylic resin below the upper limit, the adhesive force between the thermosetting resin film and its cured product and the adherend can be improved.

[0233] Examples of the acrylic resin include polymers of one or more (meth)acrylates; copolymers of two or more monomers selected from (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N-methylol acrylamide.

[0234] Examples of the (meth)acrylate constituting the acrylic resin 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, isononyl (meth)acrylate, Alkyl (meth)acrylates in which the alkyl group constituting the alkyl ester is a chain structure having 1 to 18 carbon atoms, such as 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, octadecyl (meth)acrylate (stearate (meth)acrylate);

[0235] Cycloalkyl (meth)acrylates such as isobornyl (meth)acrylate and dicyclopentyl (meth)acrylate;

[0236] Aralkyl (meth)acrylates such as benzyl (meth)acrylate;

[0237] Cycloalkenyl (meth)acrylates such as dicyclopentenyl (meth)acrylate;

[0238] Cycloalkenyloxyalkyl (meth)acrylates such as dicyclopentenyloxyethyl (meth)acrylate;

[0239] (Meth)acrylic acid imide;

[0240] Glycidyl (meth)acrylates such as glycidyl (meth)acrylate;

[0241] (meth)acrylates containing hydroxy groups, 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;

[0242] (Meth)acrylates containing a substituted amino group such as N-methylaminoethyl (meth)acrylate, etc. Here, "substituted amino group" means a group in which one or two hydrogen atoms of an amino group are substituted with a group other than a hydrogen atom.

[0243] In addition to the (meth)acrylate, the acrylic resin may be obtained by copolymerizing one or more monomers selected from (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N-hydroxymethyl acrylamide.

[0244] The monomers constituting the acrylic resin may be one kind or two or more kinds. When there are two or more kinds, the combination and ratio thereof may be arbitrarily selected.

[0245] The acrylic resin may have a functional group such as a vinyl group, a (meth)acryloyl group, an amino group, a hydroxyl group, a carboxyl group, an isocyanate group, etc. that can be bonded to other compounds. The functional group of the acrylic resin may be bonded to other compounds via a crosslinking agent (F) described later, or may be directly bonded to other compounds without a crosslinking agent (F). The acrylic resin is bonded to other compounds via the functional group, and thus the reliability of the package obtained using the first protective film forming sheet tends to be improved.

[0246] In the present invention, for example, as the polymer component (A), instead of using polyvinyl acetal and acrylic resin, a thermoplastic resin other than polyvinyl acetal and acrylic resin (hereinafter, sometimes simply referred to as "thermoplastic resin") may be used alone, or the thermoplastic resin and polyvinyl acetal or acrylic resin may be used simultaneously. By using the thermoplastic resin, sometimes the peelability of the first protective film from the first supporting sheet is improved, or the thermosetting resin film easily follows the concave-convex surface of the adherend, which can further suppress the generation of gaps between the adherend and the thermosetting resin film.

[0247] The weight average molecular weight of the thermoplastic resin is preferably 1,000 to 100,000, more preferably 3,000 to 80,000.

[0248] The glass transition temperature (Tg) of the thermoplastic resin is preferably -30 to 150°C, more preferably -20 to 120°C.

[0249] Examples of the thermoplastic resin include polyester resins, polyurethane resins, phenoxy resins, polybutene, polybutadiene, and polystyrene.

[0250] The thermoplastic resin contained in the composition (III-1) and the thermosetting resin film may be one kind or two or more kinds. When two or more kinds are used, the combination and ratio thereof may be arbitrarily selected.

[0251] In the composition (III-1), regardless of the type of the polymer component (A), the ratio of the content of the polymer component (A) to the total content of all components except the solvent (i.e., the ratio of the content of the polymer component (A) in the thermosetting resin film to the total mass of the thermosetting resin film) can be, for example, any range of 5 to 60 mass%, 5 to 45 mass%, 5 to 30 mass% and 5 to 15 mass%.

[0252] The polymer component (A) may also be a thermosetting component (B). In the present invention, when the composition (III-1) contains a component that is both a polymer component (A) and a thermosetting component (B), the composition (III-1) is deemed to contain the polymer component (A) and the thermosetting component (B).

[0253] [Thermosetting component (B)]

[0254] The thermosetting component (B) has thermosetting properties and is a component for thermally curing the thermosetting resin film to form a hard first protective film.

[0255] In the thermosetting resin film, the thermosetting component (B) belongs to both the "thermosetting component" that defines the ratio of the above-mentioned total content and the "thermosetting component" that is the object of calculation of the above-mentioned X value.

[0256] The thermosetting component (B) contained in the composition (III-1) and the thermosetting resin film may be one kind or two or more kinds. When there are two or more kinds, the combination and ratio thereof may be arbitrarily selected.

[0257] Examples of the thermosetting component (B) include epoxy-based thermosetting resins, polyimide resins, and unsaturated polyester resins.

[0258] Among them, the thermosetting component (B) is preferably an epoxy-based thermosetting resin.

[0259] (Epoxy thermosetting resin)

[0260] The epoxy thermosetting resin is composed of an epoxy resin (B1) and a thermosetting agent (B2).

[0261] In the thermosetting resin film, the epoxy resin (B1) and the thermosetting agent (B2) are both "thermosetting components" that define the above-mentioned total content ratio and "thermosetting components" that are the objects of calculation of the above-mentioned X value.

[0262] The epoxy-based thermosetting resin contained in the composition (III-1) and the thermosetting resin film may be of one kind or of two or more kinds. When there are two or more kinds, the combination and ratio thereof may be arbitrarily selected.

[0263] Epoxy resin (B1)

[0264] As the epoxy resin (B1), known epoxy resins can be listed, for example, epoxy compounds with difunctionality or higher such as polyfunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ether and its hydride, o-cresol novolac epoxy resin, dicyclopentadiene epoxy resin, biphenyl epoxy resin, bisphenol A epoxy resin, bisphenol F epoxy resin, and phenylene skeleton epoxy resin can be listed.

[0265] As the epoxy resin (B1), an epoxy resin having an unsaturated hydrocarbon group may also be used. The compatibility of the epoxy resin having an unsaturated hydrocarbon group with the acrylic resin is greater than the compatibility of the epoxy resin not having an unsaturated hydrocarbon group with the acrylic resin. Therefore, by using the epoxy resin having an unsaturated hydrocarbon group, the reliability of the workpiece with the first protective film obtained by using the first protective film forming sheet is improved.

[0266] Examples of epoxy resins having an unsaturated hydrocarbon group include compounds in which part of the epoxy groups of a polyfunctional epoxy resin is converted into a group having an unsaturated hydrocarbon group. Such compounds can be obtained, for example, by subjecting (meth)acrylic acid or a derivative thereof to an epoxy group by an addition reaction.

[0267] Examples of the epoxy resin 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.

[0268] The unsaturated hydrocarbon group is a polymerizable unsaturated group, and specific examples thereof include an ethylene (vinyl) group, a 2-propenyl (allyl) group, a (meth)acryloyl group, and a (meth)acrylamide group. An acryloyl group is preferred.

[0269] The number average molecular weight of the epoxy resin (B1) is not particularly limited, but is preferably 300 to 30,000, more preferably 300 to 10,000, and particularly preferably 300 to 3,000 from the viewpoint of curability of the thermosetting resin film and strength and heat resistance of the cured resin film.

[0270] The epoxy equivalent of the epoxy resin (B1) is preferably 100 to 1000 g / eq, more preferably 150 to 970 g / eq, and further preferably 200 to 600 g / eq.

[0271] The epoxy resin (B1) may be used alone or in combination of two or more. When two or more kinds are used in combination, the combination and ratio thereof may be arbitrarily selected.

[0272] Thermal curing agent (B2)

[0273] The thermosetting agent (B2) functions as a curing agent for the epoxy resin (B1).

[0274] Examples of the thermosetting agent (B2) include compounds having two or more functional groups that can react with an epoxy group in one molecule. Examples of the functional group include phenolic hydroxyl groups, alcoholic hydroxyl groups, amino groups, carboxyl groups, and groups formed by anhydriding an acid group. Phenolic hydroxyl groups, amino groups, or groups formed by anhydriding an acid group are preferred, and phenolic hydroxyl groups or amino groups are more preferred.

[0275] Examples of the phenolic curing agent having a phenolic hydroxyl group in the thermosetting agent (B2) include polyfunctional phenol resins, biphenol, novolak-type phenol resins, dicyclopentadiene-type phenol resins, and aralkyl-type phenol resins.

[0276] As an amine curing agent which has an amino group in a thermosetting agent (B2), dicyandiamide etc. are mentioned, for example.

[0277] The heat curing agent (B2) may have an unsaturated hydrocarbon group.

[0278] Examples of the thermosetting agent (B2) having an unsaturated hydrocarbon group include compounds in which part of the hydroxyl groups of a phenolic resin are substituted with a group having an unsaturated hydrocarbon group, and compounds in which a group having an unsaturated hydrocarbon group is directly bonded to an aromatic ring of a phenolic resin.

[0279] The unsaturated hydrocarbon group in the thermosetting agent (B2) is the same as the unsaturated hydrocarbon group in the above-mentioned epoxy resin having an unsaturated hydrocarbon group.

[0280] When a phenolic curing agent is used as the thermosetting agent (B2), the thermosetting agent (B2) preferably has a high softening point or glass transition temperature from the viewpoint of improving the releasability of the first protective film from the first supporting sheet.

[0281] In the thermosetting agent (B2), the number average molecular weight of the resin component such as a polyfunctional phenol resin, a novolac phenol resin, a dicyclopentadiene phenol resin, an aralkyl phenol resin is preferably 300 to 30,000, more preferably 400 to 10,000, and particularly preferably 500 to 3,000.

[0282] In the thermosetting agent (B2), the molecular weight of non-resin components such as biphenol and dicyandiamide is not particularly limited, but is preferably 60 to 500, for example.

[0283] The thermosetting agent (B2) may be used alone or in combination of two or more. When two or more types are used in combination, the combination and ratio thereof may be arbitrarily selected.

[0284] In the composition (III-1) and the thermosetting resin film, the content of the thermosetting agent (B2) can be, for example, any range of 0.1 to 500 parts by mass, 1 to 250 parts by mass, 1 to 150 parts by mass, 1 to 100 parts by mass, 1 to 75 parts by mass, and 1 to 50 parts by mass relative to 100 parts by mass of the epoxy resin (B1). By making the content of the thermosetting agent (B2) above the lower limit, it is easier to cure the thermosetting resin film. By making the content of the thermosetting agent (B2) below the upper limit, the moisture absorption rate of the thermosetting resin film is reduced, and the reliability of the package obtained using the first protective film forming sheet is further improved.

[0285] In the composition (III-1) and the thermosetting resin film, the content of the thermosetting component (B) (for example, the total content of the epoxy resin (B1) and the thermosetting agent (B2)) relative to 100 parts by mass of the polymer component (A) can be, for example, 300 to 1400 parts by mass, 400 to 1300 parts by mass, 500 to 1100 parts by mass, 600 to 1000 parts by mass, and 700 to 900 parts by mass. By making the content of the thermosetting component (B) within this range, for example, the adhesive force between the first protective film and the first supporting sheet can be suppressed, and the peelability of the first supporting sheet can be improved.

[0286] [Curing accelerator (C)]

[0287] The composition (III-1) and the thermosetting resin film may contain a curing accelerator (C). The curing accelerator (C) is a component for adjusting the curing speed of the composition (III-1).

[0288] Preferred curing accelerators (C) include, for example, tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol; imidazoles (imidazoles in which one or more hydrogen atoms are replaced by groups other than hydrogen atoms) such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, and 2-phenyl-4-methyl-5-hydroxymethylimidazole; organic phosphines (phosphines in which one or more hydrogen atoms are replaced by organic groups) such as tributylphosphine, diphenylphosphine, and triphenylphosphine; tetraphenylboron salts such as tetraphenylphosphoniumtetraphenylborate and triphenylphosphinetetraphenylborate, and the like.

[0289] The curing accelerator (C) contained in the composition (III-1) and the thermosetting resin film may be one kind or two or more kinds. When two or more kinds are used, the combination and ratio thereof may be arbitrarily selected.

[0290] When a curing accelerator (C) is used, in the composition (III-1) and the thermosetting resin film, the content of the curing accelerator (C) can be, for example, any range of 0.01 to 10 parts by mass and 0.1 to 7 parts by mass relative to 100 parts by mass of the content of the thermosetting component (B). By making the content of the curing accelerator (C) above the lower limit, the effect of using the curing accelerator (C) can be more significantly obtained. By making the content of the curing accelerator (C) below the upper limit, for example, the effect of suppressing the high-polarity curing accelerator (C) from moving to the bonding interface side with the adherend in the thermosetting resin film under high temperature and high humidity conditions and causing segregation becomes higher. As a result, the reliability of the workpiece processed with the first protective film obtained using the first protective film forming sheet is further improved.

[0291] [Filling material (D)]

[0292] The composition (III-1) and the thermosetting resin film may also contain a filler (D). By making the thermosetting resin film contain a filler (D), it becomes easy to adjust the thermal expansion coefficient of the first protective film obtained by curing the thermosetting resin film. In addition, by optimizing the thermal expansion coefficient for the object of forming the first protective film, the reliability of the workpiece with the first protective film obtained using the first protective film forming sheet is further improved. In addition, by making the thermosetting resin film contain a filler (D), it is also possible to reduce the moisture absorption rate of the first protective film or improve the heat dissipation.

[0293] The filler (D) may be any of an organic filler and an inorganic filler, and is preferably an inorganic filler.

[0294] Preferred inorganic fillers include, for example, powders of silica, alumina, talc, calcium carbonate, titanium dioxide, red iron oxide, silicon carbide, boron nitride, etc.; beads obtained by sphericalizing these inorganic fillers; surface-modified products of these inorganic fillers; single crystal fibers of these inorganic fillers; glass fibers, etc.

[0295] Among them, the inorganic filler is preferably silicon dioxide or aluminum oxide, and more preferably silicon dioxide.

[0296] The average particle size of the filler (D) may be appropriately selected depending on the purpose and is not particularly limited, but may be, for example, 0.02 to 2 μm.

[0297] In this specification, unless otherwise specified, the "average particle size" refers to the particle size at the cumulative value of 50% in the particle size distribution curve obtained by laser diffraction scattering method (D 50 ) value.

[0298] The filler (D) contained in the composition (III-1) and the thermosetting resin film may be one kind or two or more kinds. When two or more kinds are used, the combination and ratio thereof may be arbitrarily selected.

[0299] In the composition (III-1), the ratio of the content of the filler (D) to the total content of all components except the solvent (i.e., the ratio of the content of the filler (D) in the thermosetting resin film to the total mass of the thermosetting resin film) can be, for example, any of 3 to 60 mass%, 4 to 40 mass%, 5 to 30 mass%, 5 to 20 mass% and 5 to 15 mass%. By making the ratio within this range, it is easier to adjust the thermal expansion coefficient of the first protective film.

[0300] [Coupling agent (E)]

[0301] The composition (III-1) and the thermosetting resin film may also contain a coupling agent (E). By using a compound having a functional group that can react with an inorganic compound or an organic compound as the coupling agent (E), the adhesion and tightness of the thermosetting resin film to the adherend can be improved. In addition, by using a coupling agent (E), the water resistance of the cured product of the thermosetting resin film is improved without impairing the heat resistance.

[0302] The coupling agent (E) is preferably a compound having a functional group that can react with a functional group possessed by the polymer component (A), the thermosetting component (B), etc., and is more preferably a silane coupling agent.

[0303] Preferred silane coupling agents include, for example, 3-glycidyloxypropyl trimethoxysilane, 3-glycidyloxypropyl methyl diethoxysilane, 3-glycidyloxypropyl triethoxysilane, 3-glycidyloxymethyl diethoxysilane, 2-(3,4-epoxycyclohexyl)ethyl trimethoxysilane, 3-methacryloxypropyl trimethoxysilane, 3-aminopropyl trimethoxysilane, 3-(2-aminoethylamino)propyl trimethoxysilane, Methoxysilane, 3-(2-aminoethylamino)propylmethyldiethoxysilane, 3-(phenylamino)propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3-ureapropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, bis(3-triethoxysilylpropyl)tetrasulfide, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, imidazolesilane, etc.

[0304] The coupling agent (E) contained in the composition (III-1) and the thermosetting resin film may be one kind or two or more kinds. When two or more kinds are used, the combination and ratio thereof may be arbitrarily selected.

[0305] When a coupling agent (E) is used, the content of the coupling agent (E) in the composition (III-1) and the thermosetting resin film can be, for example, any range of 0.03 to 20 parts by mass, 0.05 to 10 parts by mass, and 0.1 to 5 parts by mass relative to 100 parts by mass of the total content of the polymer component (A) and the thermosetting component (B). By making the content of the coupling agent (E) above the lower limit, the effect of using the coupling agent (E) can be more significantly obtained, that is, improving the dispersibility of the filler (D) in the resin, improving the adhesion between the thermosetting resin film and the adherend, etc. By making the content of the coupling agent (E) below the upper limit, the generation of degassing can be further suppressed.

[0306] [Crosslinking agent (F)]

[0307] When the above-mentioned acrylic resin or the like having a functional group such as a vinyl group, a (meth)acryloyl group, an amino group, a hydroxyl group, a carboxyl group, an isocyanate group, etc. that can be bonded to other compounds is used as the polymer component (A), the composition (III-1) and the thermosetting resin film may also contain a crosslinking agent (F). The crosslinking agent (F) is a component for bonding the functional group in the polymer component (A) to other compounds and crosslinking, and by crosslinking in this manner, the initial adhesive force and cohesive force of the thermosetting resin film can be adjusted.

[0308] Examples of the crosslinking agent (F) include organic polyisocyanate compounds, organic polyimide compounds, metal chelate crosslinking agents (crosslinking agents having a metal chelate structure), and aziridine crosslinking agents (crosslinking agents having an aziridine group).

[0309] As the organic polyisocyanate compound, for example, aromatic polyisocyanate compounds, aliphatic polyisocyanate compounds and alicyclic polyisocyanate compounds (hereinafter, these compounds are sometimes collectively referred to as "aromatic polyisocyanate compounds, etc."); trimers, isocyanurates and adducts of the aromatic polyisocyanate compounds, etc.; terminal isocyanate urethane prepolymers obtained by reacting the aromatic polyisocyanate compounds, etc. with polyol compounds, etc. The "adduct" refers to the 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. As an example of the adduct, the xylene diisocyanate adduct of trimethylolpropane described later can be cited. In addition, the "terminal isocyanate urethane prepolymer" refers to a prepolymer having a urethane bond and an isocyanate group at the terminal of the molecule.

[0310] More specifically, the organic polyisocyanate compound includes, for example, 2,4-toluene diisocyanate; 2,6-toluene 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 any one or more of toluene diisocyanate, hexamethylene diisocyanate and xylylene diisocyanate are added to all or part of the hydroxyl groups of a polyol such as trimethylolpropane; lysine diisocyanate, etc.

[0311] Examples of the organic polyimide compound include N,N′-diphenylmethane-4,4′-bis(1-aziridinecarboxamide), trimethylolpropane-tris-β-aziridine propionate, tetramethylolmethane-tris-β-aziridine propionate, and N,N′-toluene-2,4-bis(1-aziridinecarboxamide)triethylenemelamine.

[0312] When an organic polyisocyanate compound is used as the crosslinking agent (F), a hydroxyl-containing polymer is preferably used as the polymer component (A). When the crosslinking agent (F) has an isocyanate group and the polymer component (A) has a hydroxyl group, a crosslinking structure can be easily introduced into the thermosetting resin film by the reaction of the crosslinking agent (F) and the polymer component (A).

[0313] The crosslinking agent (F) contained in the composition (III-1) and the thermosetting resin film may be one kind or two or more kinds. When two or more kinds are used, the combination and ratio thereof may be arbitrarily selected.

[0314] When a crosslinking agent (F) is used, the content of the crosslinking agent (F) in the composition (III-1) can be, for example, any range of 0.01 to 20 parts by mass, 0.1 to 10 parts by mass, and 0.5 to 5 parts by mass relative to 100 parts by mass of the polymer component (A). By making the content of the crosslinking agent (F) above the lower limit, the effect of using the crosslinking agent (F) can be more significantly obtained. By making the content of the crosslinking agent (F) below the upper limit, excessive use of the crosslinking agent (F) can be suppressed.

[0315] [Energy ray curable resin (G)]

[0316] The composition (III-1) and the thermosetting resin film may contain an energy-ray curable resin (G). When the thermosetting resin film contains an energy-ray curable resin (G), the properties can be changed by irradiation with energy rays.

[0317] The energy-ray-curable resin (G) is obtained by polymerizing (curing) an energy-ray-curable compound.

[0318] Examples of the energy-ray-curable compound include compounds having at least one polymerizable double bond in the molecule, and acrylate compounds having a (meth)acryloyl group are preferred.

[0319] Examples of the acrylate compounds include (meth)acrylates containing a chain aliphatic skeleton, such as trimethylolpropane tri(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butanediol di(meth)acrylate, and 1,6-hexanediol di(meth)acrylate; (meth)acrylates containing a cyclic aliphatic skeleton, such as dicyclopentyl di(meth)acrylate; polyalkylene glycol (meth)acrylates, such as polyethylene glycol di(meth)acrylate; oligoester (meth)acrylates; urethane (meth)acrylate oligomers; epoxy-modified (meth)acrylates; polyether (meth)acrylates other than the polyalkylene glycol (meth)acrylates; itaconic acid oligomers, and the like.

[0320] The weight average molecular weight of the energy ray curable compound is preferably 100 to 30,000, more preferably 300 to 10,000.

[0321] The energy ray-curable compound used in the polymerization may be one kind or two or more kinds. When two or more kinds are used, the combination and ratio thereof may be arbitrarily selected.

[0322] The energy-ray-curable resin (G) contained in the composition (III-1) and the thermosetting resin film may be one kind or two or more kinds. When two or more kinds are used, the combination and ratio thereof may be arbitrarily selected.

[0323] When an energy-ray curable resin (G) is used, the content of the energy-ray curable resin (G) in the composition (III-1) relative to the total mass of the composition (III-1) may be, for example, in any range of 1 to 95 mass %, 5 to 90 mass % and 10 to 85 mass %.

[0324] [Photopolymerization initiator (H)]

[0325] When the composition (III-1) and the thermosetting resin film contain the energy-ray curable resin (G), a photopolymerization initiator (H) may be contained in order to effectively promote the polymerization reaction of the energy-ray curable resin (G).

[0326] Examples of the photopolymerization initiator (H) in the composition (III-1) include benzoin compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, benzoin benzoic acid methyl ester, and benzoin dimethyl ketal; acetophenone compounds such as acetophenone, 2-hydroxy-2-methyl-1-phenyl-propane-1-one, and 2,2-dimethoxy-1,2-diphenylethane-1-one; phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2,4,6-trimethylbenzoyldiphenyl Phosphine oxide and other acylphosphine oxide compounds; benzylphenyl sulfide, tetramethylthiuram monosulfide and other sulfides; α-keto alcohol 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; benzil; dibenzil; benzophenone; 2,4-diethylthioxanthone; 1,2-diphenylmethane; 2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]acetone; 2-chloroanthraquinone, etc.

[0327] Examples of the photopolymerization initiator include quinone compounds such as 1-chloroanthraquinone and photosensitizers such as amines.

[0328] The photopolymerization initiator (H) contained in the composition (III-1) and the thermosetting resin film may be one kind or two or more kinds. When two or more kinds are used, the combination and ratio thereof may be arbitrarily selected.

[0329] When a photopolymerization initiator (H) is used, the content of the photopolymerization initiator (H) in the composition (III-1) can be, for example, in any range of 0.1 to 20 parts by mass, 1 to 10 parts by mass, and 2 to 5 parts by mass relative to 100 parts by mass of the energy ray curable resin (G).

[0330] [Colorant (I)]

[0331] The composition (III-1) and the thermosetting resin film may contain a coloring agent (I).

[0332] Examples of the colorant (I) include known colorants such as inorganic pigments, organic pigments, and organic dyes.

[0333] Examples of the organic pigments and organic dyes include amine pigments, cyanine pigments, merocyanine pigments, croconium pigments, squarylium pigments, azulenium pigments, polymethine pigments, naphthoquinone pigments, pyrylium pigments, phthalocyanine pigments, naphthalocyanine pigments, naphtholactam pigments, azo pigments, condensed coupler pigments, Nitrogen pigments, indigo pigments, perinone pigments, perylene pigments, dioxazine pigments, quinacridone pigments, isoindolinone pigments, quinophthalone pigments, pyrrole pigments, thioindigo pigments, metal complex pigments (metal complex salt dyes), dithiol metal complex pigments, indoxyl pigments, triarylmethane pigments, anthraquinone pigments, naphthol pigments, azomethine pigments, benzimidazolone pigments, pyranthrone pigments and threne pigments, etc.

[0334] Examples of the inorganic pigments include carbon black, cobalt pigments, iron pigments, chromium pigments, titanium pigments, vanadium pigments, zirconium pigments, molybdenum pigments, ruthenium pigments, platinum pigments, ITO (indium tin oxide) pigments, and ATO (antimony tin oxide) pigments.

[0335] The colorant (I) contained in the composition (III-1) and the thermosetting resin film may be one kind or two or more kinds. When two or more kinds are used, the combination and ratio thereof may be arbitrarily selected.

[0336] When a colorant (I) is used, the content of the colorant (I) of the thermosetting resin film can be appropriately adjusted according to the purpose. For example, in the composition (III-1), the ratio of the content of the colorant (I) to the total content of all components other than the solvent (i.e., the ratio of the content of the colorant (I) in the thermosetting resin film to the total mass of the thermosetting resin film) can be 0.1 to 5% by mass. By making the ratio above the lower limit, the effect of using the colorant (I) can be more significantly obtained. By making the ratio below the upper limit, the light transmittance of the thermosetting resin film can be suppressed from being excessively reduced.

[0337] [General purpose additives (J)]

[0338] The composition (III-1) and the thermosetting resin film may further contain a general-purpose additive (J) within a range not impairing the effects of the present invention.

[0339] The general-purpose additive (J) may be a known additive and may be arbitrarily selected according to the purpose without particular limitation. Preferred general-purpose additives (J) include, for example, plasticizers, antistatic agents, antioxidants, gettering agents, and the like.

[0340] The general-purpose additive (J) contained in the composition (III-1) and the thermosetting resin film may be one kind or two or more kinds. When two or more kinds are used, the combination and ratio thereof may be arbitrarily selected.

[0341] The content of the common additive (J) in the composition (III-1) and the thermosetting resin film is not particularly limited and may be appropriately selected depending on the purpose.

[0342] [Solvent]

[0343] The composition (III-1) preferably further contains a solvent. The composition (III-1) containing a solvent has good handleability.

[0344] The solvent is not particularly limited, but preferred solvents include, for example, hydrocarbons such as toluene and xylene; alcohols such as methanol, ethanol, 2-propanol, isobutanol (2-methylpropane-1-ol), and 1-butanol; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; amides (compounds having an amide bond) such as dimethylformamide and N-methylpyrrolidone, etc.

[0345] The solvent contained in the composition (III-1) may be only one kind or two or more kinds. When there are two or more kinds, the combination and ratio thereof can be arbitrarily selected.

[0346] The solvent contained in the composition (III-1) is preferably methyl ethyl ketone or the like from the viewpoint of being able to more uniformly mix the components contained in the composition (III-1).

[0347] The content of the solvent in the composition (III-1) is not particularly limited and may be appropriately selected depending on the types of components other than the solvent, for example.

[0348] As an example of a preferred thermosetting resin film of this embodiment, there can be mentioned:

[0349] A thermosetting resin film is a thermosetting resin film for forming a first protective film on a surface of a workpiece having a convex electrode by being attached to the surface and thermally cured.

[0350] The thermosetting resin film contains two or more thermosetting components other than the acrylic resin having an epoxy group.

[0351] The total content of all kinds of the thermosetting components in the thermosetting resin film is 40% by mass or more relative to the total mass of the thermosetting resin film.

[0352] When the value of X calculated by the following formula is obtained for each type of the thermosetting component contained in the thermosetting resin film, and the total value of the values ​​of X of all types of the thermosetting components contained in the thermosetting resin film is obtained, the total value is 400 g / eq or less, and the transmittance of a layer of the thermosetting resin film with a thickness of 200 μm, or a laminated film with a total thickness of 200 μm formed by laminating two or more layers of the thermosetting resin film with a thickness of less than 200 μm, at a wavelength of 1342 nm is 50% or more.

[0353] X = [equivalent weight of functional groups of the thermosetting component that participate in the thermosetting reaction (g / eq)] × [content of the thermosetting component in the thermosetting resin film (parts by mass)] / [total content of all types of thermosetting components in the thermosetting resin film (parts by mass)]

[0354] Another example of a preferred thermosetting resin film of this embodiment includes:

[0355] A thermosetting resin film is a thermosetting resin film for forming a first protective film on a surface of a workpiece having a convex electrode by being attached to the surface and thermally cured.

[0356] The thermosetting resin film contains a polymer component (A), two or more thermosetting components other than an acrylic resin having an epoxy group, and a filler (D).

[0357] The thermosetting component is composed of epoxy resin (B1) and thermosetting agent (B2).

[0358] The total content of all types of the thermosetting components in the thermosetting resin film (in other words, the total content of the epoxy resin (B1) and the thermosetting agent (B2)) is 40% by mass or more relative to the total mass of the thermosetting resin film,

[0359] The content of the polymer component (A) in the thermosetting resin film is 5 to 30% by mass relative to the total mass of the thermosetting resin film.

[0360] The content of the filler (D) in the thermosetting resin film is 5 to 20% by mass relative to the total mass of the thermosetting resin film.

[0361] When the X value calculated by the following formula is obtained for each type of the thermosetting component contained in the thermosetting resin film and the total value of the X values ​​of all types of the thermosetting components contained in the thermosetting resin film is obtained, the total value is 400 g / eq or less.

[0362] X = [equivalent weight of functional groups of the thermosetting component that participate in the thermosetting reaction (g / eq)] × [content of the thermosetting component in the thermosetting resin film (parts by mass)] / [total content of all types of thermosetting components in the thermosetting resin film (parts by mass)]

[0363] Another example of a preferred thermosetting resin film of this embodiment includes:

[0364] A thermosetting resin film is a thermosetting resin film for forming a first protective film on a surface of a workpiece having a convex electrode by being attached to the surface and thermally cured.

[0365] The thermosetting resin film contains a polymer component (A), two or more thermosetting components other than an acrylic resin having an epoxy group, and a filler (D).

[0366] The thermosetting component is composed of epoxy resin (B1) and thermosetting agent (B2).

[0367] The total content of all types of the thermosetting components in the thermosetting resin film (in other words, the total content of the epoxy resin (B1) and the thermosetting agent (B2)) is 40% by mass or more relative to the total mass of the thermosetting resin film,

[0368] The content of the polymer component (A) in the thermosetting resin film is 5 to 30% by mass relative to the total mass of the thermosetting resin film.

[0369] The content of the filler (D) in the thermosetting resin film is 5 to 20% by mass relative to the total mass of the thermosetting resin film.

[0370] When the value of X calculated by the following formula is obtained for each type of the thermosetting component contained in the thermosetting resin film, and the total value of the values ​​of X of all types of the thermosetting components contained in the thermosetting resin film is obtained, the total value is 400 g / eq or less, and the transmittance of a layer of the thermosetting resin film with a thickness of 200 μm, or a laminated film with a total thickness of 200 μm formed by laminating two or more layers of the thermosetting resin film with a thickness of less than 200 μm, at a wavelength of 1342 nm is 50% or more.

[0371] X = [equivalent weight of functional groups of the thermosetting component that participate in the thermosetting reaction (g / eq)] × [content of the thermosetting component in the thermosetting resin film (parts by mass)] / [total content of all types of thermosetting components in the thermosetting resin film (parts by mass)]

[0372] Another example of a preferred thermosetting resin film of this embodiment includes:

[0373] A thermosetting resin film is a thermosetting resin film for forming a first protective film on a surface of a workpiece having a convex electrode by being attached to the surface and thermally cured.

[0374] The thermosetting resin film contains a polymer component (A), two or more thermosetting components other than an acrylic resin having an epoxy group, and a filler (D).

[0375] The thermosetting component is composed of epoxy resin (B1) and thermosetting agent (B2).

[0376] The total content of all types of the thermosetting components in the thermosetting resin film (in other words, the total content of the epoxy resin (B1) and the thermosetting agent (B2)) is 40% by mass or more relative to the total mass of the thermosetting resin film,

[0377] The content of the polymer component (A) in the thermosetting resin film is 5 to 30% by mass relative to the total mass of the thermosetting resin film.

[0378] The content of the filler (D) in the thermosetting resin film is 5 to 20% by mass relative to the total mass of the thermosetting resin film.

[0379] When the value of X calculated by the following formula is obtained for each type of the thermosetting component contained in the thermosetting resin film, and the total value of the values ​​of X of all types of the thermosetting components contained in the thermosetting resin film is obtained, the total value is 400 g / eq or less, and a first protective film having a size of 20 mm×130 mm and a thickness of 40 μm is obtained by heating the thermosetting resin film at 130° C. for 2 hours to thermally cure it, the distance between the clamps is set to 80 mm, the stretching speed is set to 200 mm / min, and the first protective film is stretched in a direction parallel to the surface of the first protective film by the clamps, and the breaking strength of the first protective film is 55 MPa or less.

[0380] X = [equivalent weight of functional groups of the thermosetting component that participate in the thermosetting reaction (g / eq)] × [content of the thermosetting component in the thermosetting resin film (parts by mass)] / [total content of all types of thermosetting components in the thermosetting resin film (parts by mass)]

[0381] Another example of a preferred thermosetting resin film of this embodiment includes:

[0382] A thermosetting resin film is a thermosetting resin film for forming a first protective film on a surface of a workpiece having a convex electrode by being attached to the surface and thermally cured.

[0383] The thermosetting resin film contains a polymer component (A), two or more thermosetting components other than an acrylic resin having an epoxy group, and a filler (D).

[0384] The thermosetting component is composed of epoxy resin (B1) and thermosetting agent (B2).

[0385] The total content of all types of the thermosetting components in the thermosetting resin film (in other words, the total content of the epoxy resin (B1) and the thermosetting agent (B2)) is 40% by mass or more relative to the total mass of the thermosetting resin film,

[0386] The content of the polymer component (A) in the thermosetting resin film is 5 to 30% by mass relative to the total mass of the thermosetting resin film.

[0387] The content of the filler (D) in the thermosetting resin film is 5 to 20% by mass relative to the total mass of the thermosetting resin film.

[0388] When the value of X calculated by the following formula is obtained for each type of the thermosetting component contained in the thermosetting resin film, and the total value of the values ​​of X of all types of the thermosetting components contained in the thermosetting resin film is obtained, the total value is 400 g / eq or less,

[0389] The light transmittance of the thermosetting resin film having a thickness of 200 μm or the laminated film having a total thickness of 200 μm formed by laminating two or more thermosetting resin films having a thickness of less than 200 μm is 50% or more at a wavelength of 1342 nm.

[0390] A first protective film with a size of 20 mm×130 mm and a thickness of 40 μm is obtained by heating the thermosetting resin film at 130°C for 2 hours to thermally cure it. The distance between the clamps is set to 80 mm, the stretching speed is set to 200 mm / min, and the first protective film is stretched along a direction parallel to the surface of the first protective film by the clamps. At this time, the breaking strength of the first protective film is less than 55 MPa.

[0391] X = [equivalent weight of functional groups of the thermosetting component that participate in the thermosetting reaction (g / eq)] × [content of the thermosetting component in the thermosetting resin film (parts by mass)] / [total content of all types of thermosetting components in the thermosetting resin film (parts by mass)]

[0392] <<Method for preparing thermosetting resin layer-forming composition>>

[0393] The composition for forming a thermosetting resin layer such as the composition (III-1) can be obtained by blending the respective components constituting the composition.

[0394] The order of adding the components when blending them is not particularly limited, and two or more components may be added simultaneously.

[0395] When a solvent is used, the solvent may be mixed with any blending components other than the solvent to dilute the blending components in advance and then used, or the solvent may be mixed with the blending components without diluting the blending components in advance and then used.

[0396] The method for mixing the components during blending is not particularly limited, and may be appropriately selected from the following known methods: a method of mixing by rotating a stirring bar or a stirring blade, a method of mixing by using a mixer, a method of mixing by applying ultrasonic waves, and the like.

[0397] The temperature and time for adding and mixing the components are not particularly limited as long as the components do not deteriorate, and may be appropriately adjusted. However, the temperature is preferably 15 to 30°C.

[0398] ◇Method for producing the first protective film-forming sheet

[0399] The first protective film-forming sheet can be manufactured by sequentially laminating the above-mentioned layers in a corresponding positional relationship. The formation method of each layer is the same as described above.

[0400] For example, when manufacturing the first supporting sheet, when laminating the first adhesive layer or the first intermediate layer on the first substrate, the above-mentioned first adhesive composition or the first intermediate layer forming composition is applied on the first substrate and dried or irradiated with energy rays as needed, thereby laminating the first adhesive layer or the first intermediate layer.

[0401] On the other hand, for example, when further stacking a thermosetting resin layer (thermosetting resin film) on the first adhesive layer stacked on the first substrate, a thermosetting resin layer formation composition can be applied on the first adhesive layer to directly form a thermosetting resin layer. Similarly, when further stacking the first adhesive layer on the first intermediate layer stacked on the first substrate, the first adhesive composition can be applied on the first intermediate layer to directly form the first adhesive layer. In this way, when using any composition to form a continuous two-layer laminated structure, another composition can be further applied on the layer formed by the composition to form a new layer. Wherein, it is preferred to form a continuous two-layer laminated structure in the following manner: for the layer stacked later in the above-mentioned two layers, the composition is used in advance to form the layer on another release film, and the exposed surface of the formed layer and the side in contact with the release film are opposite sides and the exposed surface of the formed residual layer are fitted. At this time, it is preferred that the composition is applied on the stripping treatment surface of the release film. After forming the laminated structure, the release film is removed as needed.

[0402] For example, when manufacturing a first protective film forming sheet in which a first adhesive layer is stacked on a first substrate and a thermosetting resin layer is stacked on the first adhesive layer (a first protective film forming sheet in which the first support sheet is a stack of a first substrate and a first adhesive layer), the first adhesive layer is stacked on the first substrate by applying a first adhesive composition on the first substrate and drying it as needed, a thermosetting resin layer is formed on the release film by separately coating a thermosetting resin layer forming composition on a release film and drying it as needed, and a thermosetting resin layer is stacked on the first adhesive layer by laminating the exposed surface of the thermosetting resin layer to the exposed surface of the first adhesive layer already stacked on the first substrate, thereby obtaining a first protective film forming sheet.

[0403] In addition, for example, when manufacturing a first support sheet formed by laminating a first intermediate layer on a first substrate and laminating a first adhesive layer on the first intermediate layer, the first intermediate layer is laminated on the first substrate by coating a first intermediate layer-forming composition on the first substrate and drying it as needed, or irradiating it with energy rays, thereby laminating the first intermediate layer on the first substrate, and separately coating a first adhesive composition on a release film and drying it as needed to form a first adhesive layer on the release film, and laminating the first adhesive layer on the first intermediate layer by laminating the exposed surface of the first adhesive layer with the exposed surface of the first intermediate layer already laminated on the first substrate, thereby obtaining a first support sheet. At this time, for example, a curable resin layer is formed on the release film by further coating a thermosetting resin layer-forming composition on the release film and drying it as needed, and the exposed surface of the curable resin layer is laminated with the exposed surface of the first adhesive layer already laminated on the first intermediate layer, thereby laminating a thermosetting resin layer on the first adhesive layer, thereby obtaining a first protective film-forming sheet.

[0404] In addition, when stacking the first adhesive layer or the first intermediate layer on the first substrate, the first adhesive composition or the first intermediate layer forming composition can be coated on the release film and dried or irradiated with energy rays as needed to form the first adhesive layer or the first intermediate layer on the release film, and the exposed surface of these layers is bonded to one surface of the first substrate, thereby stacking the first adhesive layer or the first intermediate layer on the first substrate, in this way instead of the method of coating the first adhesive composition or the first intermediate layer forming composition on the first substrate.

[0405] In any method, the release film may be removed at any timing after the target layered structure is formed.

[0406] Thus, all layers constituting the first protective film forming sheet except the first substrate can be formed in advance on a release film and laminated by laminating on the surface of a target layer. Therefore, the first protective film forming sheet can be manufactured by appropriately selecting layers using such a process as needed.

[0407] In addition, the first protective film forming sheet is usually stored in a state where a release film is attached to the surface of the outermost layer (e.g., thermosetting resin layer) on the opposite side to the first support sheet. Therefore, the first protective film forming sheet can also be obtained by coating a composition for forming a layer constituting the outermost layer, such as a thermosetting resin layer forming composition, on the release film (preferably on the release treated surface) and drying it as needed, thereby forming a layer constituting the outermost layer on the release film, and stacking the remaining layers on the exposed surface of the layer opposite to the side in contact with the release film by any of the above methods, and keeping the release film attached without removal.

[0408] As the first supporting sheet, a commercially available product may be used.

[0409] ◇Method for manufacturing workpiece with first protective film

[0410] The method for preparing a workpiece with a first protective film when using a thermosetting resin film or a sheet for forming a first protective film according to an embodiment of the present invention comprises: a step of attaching a thermosetting resin film to a surface of a workpiece having a convex electrode (i.e., a convex electrode forming surface) (sometimes abbreviated as "attaching step" in this specification); a step of thermally curing the attached thermosetting resin film to form a first protective film (sometimes abbreviated as "first protective film forming step" in this specification); irradiating the workpiece with a laser through the first protective film from the side of the workpiece having the first protective film, thereby A process for forming a modified layer inside the workpiece (sometimes abbreviated as "modified layer forming process" in this specification); and a process for extending the workpiece after the modified layer is formed in a direction parallel to its circuit surface together with the first protective film, thereby dividing the workpiece at the position of the modified layer and simultaneously cutting the first protective film, thereby obtaining a workpiece processed product with a first protective film having a workpiece processed product and a first protective film formed on the surface of the workpiece processed product having the convex electrode (i.e., the convex electrode forming surface) (sometimes abbreviated as "dividing-cutting process" in this specification).

[0411] Hereinafter, the manufacturing method will be described in detail with reference to the accompanying drawings.

[0412] Figure 5A to Figure 5C ,as well as Figure 6A to Figure 6B FIG. 1 is an enlarged cross-sectional view for schematically illustrating the method for manufacturing a workpiece having a first protective film. Figure 2 The manufacturing method of the first protective film-forming sheet 1 shown will be described below.

[0413] <<Attachment process>>

[0414] In the attachment process, Figure 5A As shown, a thermosetting resin film 12 is attached to the convex electrode forming surface of the workpiece 90 (i.e., the surface 91a of the convex electrode 91 and the circuit surface 90a of the workpiece 90). By performing this process, the thermosetting resin film 12 spreads between the plurality of convex electrodes 90, closely adheres to the convex electrode forming surface, and covers the surface 91a of the convex electrode 91, especially the surface 91a of the portion near the circuit surface 90a of the workpiece 90, and buries the convex electrode 91, thereby being able to form a state of covering these areas. Furthermore, by performing this process, the upper portion of the convex electrode 91 including the top portion 910 penetrates the thermosetting resin film 12 and protrudes from the thermosetting resin film 12.

[0415] In the attaching step, for example, the thermosetting resin film 12 may be used alone, but it is preferable to use the first protective film forming sheet 1 which is composed of the first support sheet 101 and the thermosetting resin film 12 provided on the first support sheet 101 as shown here. When grinding the back surface 90b of the workpiece 90, a surface protection tape for back grinding may be used as the first support sheet 101 as described later.

[0416] In the attaching process, when using the first protective film forming sheet 1 shown here, it is sufficient to attach the thermosetting resin film 12 in the first protective film forming sheet 1 to the convex electrode forming surface of the workpiece 90, thereby attaching the first protective film forming sheet 1 itself to the convex electrode forming surface of the workpiece 90.

[0417] In addition, in this specification, the structure formed by attaching the first protective film forming sheet to the convex electrode forming surface of the workpiece shown here may be referred to as a "first stacked structure". Figure 5A , as the first stacked structure 201 , a structure in which the first protective film forming sheet 1 is attached to the convex electrode forming surface of the workpiece 90 is shown.

[0418] During the attaching process, the thermosetting resin film 12 can be attached to the convex electrode forming surface by pressing the exposed surface (sometimes referred to as the "first surface" in this specification) 12a of the thermosetting resin film 12 facing the workpiece 90 onto the convex electrode forming surface of the workpiece 90 (i.e., the surface 91a of the convex electrode 91 and the circuit surface 90a of the workpiece 90).

[0419] In the attaching step, it is preferred that the thermosetting resin film 12 is attached to the convex electrode forming surface while being heated. This can further suppress the generation of gaps between the thermosetting resin film 12 and the convex electrode forming surface, that is, between the thermosetting resin film 12 and the circuit surface 90a of the workpiece 90, and between the thermosetting resin film 12 and the surface 91a of the convex electrode 91. In addition, it can further suppress the thermosetting resin film 12 from remaining on the upper portion of the convex electrode 91 including the top portion 910, and ultimately it can further suppress the first protective film from remaining on the upper portion.

[0420] The heating temperature of the thermosetting resin film 12 during attachment may be any temperature not excessively high, and is preferably 60 to 100° C. Here, “excessively high temperature” means a temperature at which the thermosetting resin film 12 exhibits an unintended effect, such as thermal curing of the thermosetting resin film 12 .

[0421] When the thermosetting resin film 12 is attached to the convex electrode forming surface, the pressure applied to the thermosetting resin film 12 (sometimes referred to as "attachment pressure" in this specification) is preferably 0.3 to 1 MPa.

[0422] After the first stacked structure 201 is formed by the attaching process, the first stacked structure 201 can be used directly in the subsequent process, but the back surface 90b of the workpiece 90 can also be ground as needed to adjust the thickness of the workpiece 90. In addition to the difference in thickness of the workpiece 90, the first stacked structure 201 after the back surface 90b of the workpiece 90 is ground is also Figure 5A Status shown.

[0423] The back surface 90 b of the workpiece 90 can be ground by a known method such as a method using a grinder.

[0424] The thickness of the portion of the workpiece 90 excluding the protruding electrodes 91 before and after grinding the back surface 90 b of the workpiece 90 is the same as described above.

[0425] After the first stacked structure 201 is formed by the attaching step, the first support sheet 101 is removed from the thermosetting resin film 12 in the first stacked structure 201. When the back surface 90b of the workpiece 90 is ground, the first support sheet 101 is preferably removed after the grinding.

[0426] By carrying out such a process, the following can be obtained: Figure 5B As shown, a second laminated structure (in other words, a workpiece with a thermosetting resin film) 202 is provided with the thermosetting resin film 12 on the convex electrode forming surface of the workpiece 90 and is not provided with the first supporting sheet 101 .

[0427] In the second stacked structure 202 , the upper portion of the protruding electrode 91 including the top portion 910 protrudes through the thermosetting resin film 12 and is exposed.

[0428] When the first adhesive layer 13 is energy ray-curable, it is preferred that the first adhesive layer 13 be cured by irradiating energy rays to reduce the adhesiveness of the first adhesive layer 13 , and then the first supporting sheet 101 is removed from the thermosetting resin film 12 .

[0429] <<First protective film forming step>>

[0430] In the first protective film forming step, the attached thermosetting resin film 12 is thermally cured to form a protective film as shown in FIG. Figure 5C The first protective film 12' is shown.

[0431] When forming the first stacked structure 201 , the first protective film forming step may be performed after removing the first supporting sheet 101 .

[0432] Furthermore, when the back surface 90 b of the workpiece 90 is ground, the first protective film forming step may be performed after the back surface 90 b is ground.

[0433] By performing this step, a third stacked structure (in other words, a workpiece with a first protective film) 203 having the first protective film 12 ′ on the convex electrode formation surface of the workpiece 90 can be obtained. Figure 5C In the drawings, reference numeral 12a' denotes a surface of the first protective film 12' that is in contact with the workpiece 90 (in this specification, sometimes referred to as a "first surface").

[0434] As long as the first protective film 12 ′ is cured to such an extent that its function can be fully exhibited, the curing conditions of the thermosetting resin film 12 are not particularly limited and may be appropriately selected according to the type of the thermosetting resin film 12 .

[0435] For example, the heating temperature and time for thermally curing the thermosetting resin film 12 are the same as those described above.

[0436] When the thermosetting resin film 12 is thermally cured, the curable resin film 12 may be pressurized. The pressurizing pressure at this time is preferably 0.3 to 1 MPa.

[0437] exist Figure 5B In the second stacked structure (workpiece with thermosetting resin film) 202 shown, the thermosetting resin film 12 can be prevented from remaining on the upper portion including the top portion 910 of the protruding electrode 91. Therefore, the first protective film 12' can be prevented from remaining on the upper portion of the protruding electrode 91 after the present step is completed.

[0438] <<Reformed layer forming step>>

[0439] In the modified layer forming step, Fig. 6A As shown, the workpiece 90 is irradiated with the laser beam R through the first protective film 12 ′ from the side of the workpiece 90 provided with the first protective film 12 ′, thereby forming a modified layer 900 inside the workpiece 90 .

[0440] Since the workpiece 90 to be described later is divided (i.e., cut) after the modified layer forming process, it is preferred to attach a cutting sheet or a second protective film forming sheet to the back side 90b of the workpiece 90 in the third stacked structure (workpiece with a first protective film) 203, and then perform the modified layer forming process.

[0441] In this specification, such a structure including the first protective film on the convex electrode forming surface of the workpiece and the dicing sheet or the second protective film forming sheet on the back surface of the workpiece is referred to as a "fourth multilayer structure".

[0442] Furthermore, a structure having a configuration in which a reformed layer is formed inside the workpiece in the fourth stacked structure will be referred to as a "fifth stacked structure".

[0443] exist Fig. 6A, as a fifth stacked structure 205 , a structure having a first protective film 12 ′ on the convex electrode forming surface of the workpiece 90 , a second protective film forming sheet 8 on the back surface 90 b of the workpiece 90 , and a modified layer 900 formed inside the workpiece 90 is shown.

[0444] The second protective film forming sheet 8 shown here is configured to include a second base material 81 , a second adhesive layer 83 provided on the second base material 81 , and a resin layer (resin film) 82 provided on the second adhesive layer 83 .

[0445] The laminate of the second base material 81 and the second adhesive layer 83 is the second supporting sheet 801 .

[0446] Therefore, the second protective film forming sheet 8 can be said to be a laminate including the second support sheet 801 and the resin layer (resin film) 82 provided on one surface 801 a of the second support sheet 801 , in other words, on one surface 83 a of the second adhesive layer 83 .

[0447] The resin layer (resin film) 82 is used to form a second protective film on the back side 90b of the workpiece 90. The second protective film covers and protects the back side 90b of the workpiece 90. More specifically, the second protective film prevents cracks from being generated in the workpiece when the workpiece is divided or before the workpiece processed by dividing the workpiece is packaged and the target substrate device is manufactured.

[0448] The resin layer 82 may have only one of the properties of thermosetting and energy-ray curing, may have both properties, or may not have both properties. When the resin layer 82 is curable (i.e., has either of the properties of thermosetting and energy-ray curing), its cured product is the second protective film. When the resin layer 82 is non-curable (i.e., has neither of the properties of thermosetting and energy-ray curing), the second protective film is considered to be provided from the time when the resin layer 82 is attached to the back surface 90b of the workpiece 90.

[0449] The second adhesive layer 83 may be either energy-ray-curable or non-energy-ray-curable, similar to the first adhesive layer 13. The energy-ray-curable second adhesive layer 83 can easily adjust its physical properties before and after curing.

[0450] The second substrate 81 may be, for example, the same substrate as the first substrate in the first protective film-forming sheet described above (for example, the first substrate 11 in the first protective film-forming sheet 1 ).

[0451] In the above-described manufacturing method, as the second protective film-forming sheet, a protective film-forming sheet other than the second protective film-forming sheet 8 may be used.

[0452] In the above-described manufacturing method, the second protective film-forming sheet is not limited to the second protective film-forming sheet 8 , and a known protective film-forming sheet can be used.

[0453] Likewise, in the above-mentioned production method, a known cutting blade can be used as the cutting blade.

[0454] In the reformed layer forming step, a focus is set at a specific region as a division position of the workpiece 90 inside the workpiece 90, and laser light R is irradiated to be focused on the focus. By irradiating the laser light R, the reformed layer 900 is formed in the irradiated region.

[0455] The thermosetting resin film 12 and the first protective film 12' are transmissive to light of wavelength 1342nm, and preferably the light transmittance of the thermosetting resin film 12 and the first protective film 12' at wavelength 1342nm is high as described above, in which case the laser light of wavelength 1342nm is well transmitted through the first protective film 12'. Therefore, even if the laser light R is irradiated to the workpiece 90 from the side of the workpiece 90 provided with the first protective film 12', the modified layer 900 can be well formed inside the workpiece 90.

[0456] <<Splitting-cutting process>>

[0457] In the above-mentioned dividing-cutting process, the workpiece 90 after forming the modified layer 900 is cut together with the first protective film 12' along a direction parallel to the circuit surface 90a of the workpiece 90 ( Fig. 6A In other words, the fifth stacked structure 205 is extended in a direction parallel to the circuit surface 90a of the workpiece 90, thereby dividing the workpiece 90 at the location of the modified layer 900 and cutting off the first protective film 12'. Figure 6B As shown, a workpiece 990 with a first protective film is obtained, which includes a workpiece 9 and a first protective film (first protective film 120' after cutting) formed on the convex electrode forming surface of the workpiece 9 (i.e., the surface 91a of the convex electrode 91 and the circuit surface 9a of the workpiece 9).

[0458] By performing this process, a sixth stacked structure 206 can be obtained in which a plurality of (many) workpieces 9 (i.e., workpieces 990 with first protective films) are neatly arranged on the second support sheet 801, wherein the workpieces 9 have the cut first protective film 120' on the convex electrode forming surface. Figure 6B In the figure, reference numeral 120a' indicates a surface of the first protective film 120' after cutting that contacts the workpiece 9 (sometimes referred to as a "first surface" in this specification), and reference numeral 9b indicates a back surface of the workpiece 9.

[0459] By forming the first protective film 12' from the thermosetting resin film 12 that satisfies the condition of the total value of the X value, the first protective film 12' can be easily cut in the splitting-cutting step. As a result, the workpiece 9 having the cut first protective film 120' on the convex electrode forming surface can be efficiently manufactured. In this step, the first protective film 120' is cut along the split position of the workpiece 9, and finally becomes a state of being cut along the outer periphery of the workpiece 9.

[0460] In the splitting and cutting step, the expansion is preferably performed at a temperature of -15 to 5° C. By setting the expansion temperature to be below the upper limit, the first protective film 12 ′ can be cut more easily. By setting the expansion temperature to be above the lower limit, excessive cooling can be avoided.

[0461] Here, the case where the resin layer 82 in the second protective film forming sheet 8 is cut simultaneously by performing the splitting-cutting step is shown, but the resin layer 82 may be cut separately by a known method after the splitting-cutting step. Figure 6B In the figure, the resin layer 82 after cutting is denoted by reference numeral 820. In addition, although the case where the resin layer 82 is cut is shown here, it is also possible to cut the second protective film obtained by curing the resin layer 82 instead of cutting it at the stage of the resin layer 82.

[0462] In the manufacturing method, the resin layer 82 or the second protective film is cut along the dividing position of the workpiece 90 in the same manner as the first protective film 12 ′.

[0463] In this specification, as long as the stacking structure of the second support sheet and the resin layer (in other words, the second support sheet and the resin layer after cutting) can be maintained, the stacking structure is referred to as a "second protective film forming sheet" even after the resin layer is cut.

[0464] ◇Method for manufacturing substrate device

[0465] After obtaining a workpiece with a first protective film (in other words, the sixth stacked structure) by the above-mentioned manufacturing method, the workpiece with the first protective film is flip-chip connected to the circuit surface of the substrate by a known method, and then a package is made, and the target substrate device (not shown) can be manufactured by using the package. When using a semiconductor chip with a first protective film, the target semiconductor device can be manufactured by using the semiconductor package after making the semiconductor package. In addition, when using semiconductor chips with a first protective film and a second protective film, these semiconductor chips with protective films can be flip-chip connected to manufacture the target semiconductor device.

[0466] Example

[0467] The present invention will be described in more detail below using specific examples, but the present invention is not limited to the following examples.

[0468] In addition, for the sake of convenience, each object produced in the comparative example shown below is given the same name as each object produced in the example.

[0469] The components used for preparing the composition for forming a thermosetting resin layer are shown below.

[0470] [Polymer component (A)]

[0471] (A)-1: Polyvinyl butyral ("S-LEC SV-10" manufactured by SEKISUI CHEMICAL CO., LTD., weight average molecular weight 65,000, glass transition temperature 66°C)

[0472] (A)-2: Polyvinyl butyral ("S-LEC BL-10" manufactured by SEKISUI CHEMICAL CO., LTD., weight average molecular weight 25,000, glass transition temperature 59°C)

[0473] (A)-3: Acrylic resin (weight average molecular weight 800,000, glass transition temperature -28°C) copolymerized from n-butyl acrylate (55 parts by mass), methyl acrylate (10 parts by mass), glycidyl methacrylate (20 parts by mass) and 2-hydroxyethyl acrylate (15 parts by mass)

[0474] [Thermosetting component (B)]

[0475] Epoxy resin (B1)

[0476] (B1)-1: Bisphenol A type epoxy resin ("EXA-4810-1000" manufactured by DIC CORPORATION, epoxy equivalent 404 to 412 g / eq)

[0477] (B1)-2: dicyclopentadiene type epoxy resin ("EPICLON HP-7200" manufactured by DIC CORPORATION, epoxy equivalent 265 g / eq)

[0478] (B1)-3: Liquid modified epoxy resin ("YX7110" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 962 g / eq)

[0479] (B1)-4: A mixture of a liquid bisphenol A epoxy resin and acrylic rubber particles ("BPA328" manufactured by Nippon Shokubai Co., Ltd., epoxy equivalent 235 g / eq)

[0480] (B1)-5: solid bisphenol A type epoxy resin ("Epikote 1055" manufactured by Mitsubishi Chemical Corporation, molecular weight 1600, softening point 93°C, epoxy equivalent 800 to 900 g / eq)

[0481] (B1)-6: dicyclopentadiene type epoxy resin ("XD-1000-L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 248 g / eq)

[0482] Thermal curing agent (B2)

[0483] (B2)-1: Novolac type phenolic resin ("Shonol BRG-556" manufactured by Showa Denko KK, hydroxyl equivalent 104 g / eq)

[0484] (B2)-2: dicyandiamide ("ADEKA HARDENER EH-3636AS" manufactured by ADEKA CORPORATION, solid dispersion type latent curing agent, active hydrogen equivalent 21 g / eq)

[0485] [Curing accelerator (C)]

[0486] (C)-1: 2-phenyl-4,5-dihydroxymethylimidazole ("CUREZOL 2PHZ" manufactured by SHIKOKU CHEMICALS CORPORATION)

[0487] [Filling material (D)]

[0488] (D)-1: Silica filler ("YA050C-MKK" manufactured by Admatechs, average particle size 0.05 μm)

[0489] (D)-2: Silica filler (“SC2050MA” manufactured by Admatechs, a silica filler surface-modified with an epoxy compound, average particle size 500 nm)

[0490] (D)-3: Silica filler ("SV-10" manufactured by TATSUMORI LTD., average particle size 8 μm)

[0491] [Coupling agent (E)]

[0492] (E)-1: Silane coupling agent ("MKC silicate MSEP 2" manufactured by Mitsubishi Chemical Corporation, a silicate compound to which γ-glycidyloxypropyltrimethoxysilane was added)

[0493] [Colorant (I)]

[0494] (I)-1: Carbon black ("MA-600B" manufactured by Mitsubishi Chemical Corporation)

[0495] [Example 1]

[0496] <<Manufacturing of Thermosetting Resin Film and First Protective Film Forming Sheet>>

[0497] <Preparation of Thermosetting Resin Layer-Forming Composition>

[0498] The polymer component (A)-1 (9.9 parts by mass), epoxy resin (B1)-1 (37.8 parts by mass), epoxy resin (B1)-2 (25.0 parts by mass), thermosetting agent (B2)-1 (18.1 parts by mass), curing accelerator (C)-1 (0.2 parts by mass) and filler (D)-1 (9.0 parts by mass) were mixed, further diluted with methyl ethyl ketone, and stirred at 23°C to prepare a thermosetting resin layer-forming composition (III-1) having a total concentration of 55% by mass of the above 6 components except methyl ethyl ketone. These components and their contents are shown in Table 1. In addition, the "-" recorded in the column of components contained in Table 1 indicates that the thermosetting resin layer-forming composition does not contain the component. In addition, the "ratio (mass %) of the total content of all types of thermosetting components" in Table 1 refers to the "ratio of the total content of all types of thermosetting components in the thermosetting resin film relative to the total mass of the thermosetting resin film".

[0499] <Manufacturing of Thermosetting Resin Film>

[0500] A release film ("SP-PET381031" manufactured by Lintec Corporation, 38 μm in thickness) obtained by subjecting one side of a polyethylene terephthalate film to a release treatment by silicone treatment was used, and the composition for forming a thermosetting resin layer (III-1) obtained above was applied onto the release-treated surface of the release film, and dried at 100°C for 2 minutes to prepare a thermosetting resin film with a thickness of 30 μm.

[0501] <Manufacturing of the First Protective Film Forming Sheet>

[0502] Next, one surface of a back grinding surface protection tape ("Adwill E-8180HR" manufactured by Lintec Corporation) was bonded to the exposed surface of the obtained thermosetting resin film (in other words, the surface opposite to the side having the release film) to prepare a first protective film forming sheet. The surface protection tape is equivalent to the first supporting sheet.

[0503] <<Manufacturing of semiconductor chip with first protective film>>

[0504] The release film is removed from the thermosetting resin film in the first protective film forming sheet obtained above, and the exposed surface of the thermosetting resin film thus produced (in other words, the surface opposite to the side having the surface protection tape) is pressed against the bump forming surface of the semiconductor wafer, thereby attaching the first protective film forming sheet to the bump forming surface of the semiconductor wafer. At this time, the first protective film forming sheet is attached while heating the thermosetting resin film using an attaching device (roll laminator, "RAD-3510F / 12" manufactured by Lintec Corporation) under the conditions of a workbench temperature of 90°C, an attaching speed of 2mm / second, and an attaching pressure of 0.5MPa. As a semiconductor wafer, a wafer with a bump height of 210μm, a bump width of 250μm, a distance between adjacent bumps of 400μm, and a thickness of 750μm at the part other than the bumps is used.

[0505] In the above manner, a first stacked structure is obtained in which the first protective film forming sheet is attached to the bump formation surface of the semiconductor wafer.

[0506] Next, the surface (back surface) of the semiconductor wafer opposite to the bump formation surface in the obtained first stacked structure was ground using a grinder ("DGP8760" manufactured by DISCO Corporation). At this time, the back surface was ground until the thickness of the portion of the semiconductor wafer other than the bumps was 250 μm.

[0507] Next, the surface protection tape (in other words, the first supporting sheet) is removed from the thermosetting resin film in the first stacked structure.

[0508] In the above manner, a second stacked structure (semiconductor wafer with thermosetting resin film) having a thermosetting resin film on the bump formation surface of the semiconductor wafer is obtained.

[0509] Next, a heat curing device ("RAD-9100m / 12" manufactured by Lintec Corporation) was used to heat and pressurize the thermosetting resin film in the second stacked structure obtained above at a treatment temperature of 130°C, a treatment pressure of 0.5 MPa, and a treatment time of 2 hours to thermally cure it to form a first protective film.

[0510] In the above manner, a third stacked structure having the first protective film on the bump formation surface of the semiconductor wafer (in other words, a semiconductor wafer with the first protective film) is obtained.

[0511] Next, a dicing tape ("Adwill D-841" manufactured by Lintec Corporation) is attached to the back side (in other words, the polished side) of the semiconductor wafer in the obtained third stacked structure, thereby obtaining a fourth stacked structure having a first protective film on the bump formation surface of the semiconductor wafer and a dicing tape on the back side. The dicing tape is equivalent to the second supporting sheet.

[0512] Next, a dicing device ("DFL7361" manufactured by DISCO Corporation) was used to irradiate the semiconductor wafer with a laser from the side of the semiconductor wafer in the fourth stacked structure having the first protective film, with the laser focused on the focal point set inside the semiconductor wafer through the first protective film, thereby forming a modified layer inside the semiconductor wafer. At this time, the wavelength of the laser was set to 1342 nm, the output power was set to 0.7 W, and the frequency was set to 90 kHz.

[0513] In the above manner, a fifth stacked structure having a structure in which a reformed layer is formed inside the semiconductor wafer in the fourth stacked structure is obtained.

[0514] Next, under a 0°C environment, the semiconductor wafer after forming the modified layer (in other words, the fifth stacked structure) is expanded along the direction parallel to its circuit surface together with the first protective film, and the semiconductor wafer is divided at the position of the modified layer, and the first protective film is cut along the division position of the semiconductor wafer. At this time, a die separator ("DDS2300" manufactured by DISCO Corporation) is used to place the second support sheet in the fifth stacked structure on the workbench in the die separator, and the peripheral portion of the fifth stacked structure is fixed. In this state, the workbench is pushed up at a push speed of 50 mm / sec and a push amount of 20 mm, thereby expanding the semiconductor wafer and the first protective film. The size of the obtained semiconductor chip is 2 mm×2 mm.

[0515] Through the above method, a sixth stacked structure is obtained in which a plurality of (many) semiconductor chips (i.e., semiconductor chips with a first protective film) are neatly arranged on a second support sheet (in other words, the cutting tape), and the semiconductor chips have a cut first protective film on the bump forming surface.

[0516] <<Evaluation of Thermosetting Resin Film>>

[0517] <Confirmation of the residual inhibition of the thermosetting resin film on the upper part of the bump>

[0518] When manufacturing the semiconductor chip with the first protective film, a scanning electron microscope ("VE-9800" manufactured by Keyence Corporation) was used to observe the first stacked structure from the bump formation surface side of the semiconductor wafer at an acceleration voltage of 5 keV. In addition, the residual suppression of the thermosetting resin film on the upper part of the bump in the first stacked structure was evaluated according to the following evaluation criteria.

[0519] Table 1 shows the results.

[0520] (Evaluation Criteria)

[0521] A: The boundary between the bump and the thermosetting resin film was confirmed, and it was confirmed that the thermosetting resin film did not remain on the bump.

[0522] B: The boundary between the bump and the thermosetting resin film could not be confirmed, but it was confirmed that the thermosetting resin film remained on the top of the bump.

[0523] <Measurement of Light Transmittance of Thermosetting Resin Film>

[0524] Five test thermosetting resin films (thickness 40 μm) were produced in the same manner as in the above-mentioned production of the thermosetting resin film except that the coating amount of the thermosetting resin layer-forming composition (III-1) was changed.

[0525] Next, these five test thermosetting resin films were stacked in their thickness direction to obtain a laminated film (thickness 200 μm).

[0526] Next, the light transmittance of the laminated film at a wavelength of 1342 nm was measured using a spectrophotometer ("UV-VIS-NIRSPECTROPHOTOMETER UV-3600" manufactured by Shimadzu Corporation).

[0527] <<Evaluation of the first protective film>>

[0528] <Evaluation of Semiconductor Wafer Dividability>

[0529] Using a digital microscope ("VH-Z100" manufactured by Keyence Corporation), the sixth stacked structure obtained above was observed from the first protective film side of the sixth stacked structure. At this time, as the observation area, the following five areas in total were selected: the first area corresponding to the central part of the surface of the second support sheet where the semiconductor chips with the first protective film are neatly arranged, the second area, the third area, the fourth area, and the fifth area located on the side of the peripheral portion that is point-symmetrical with respect to the first area and at an equal distance from the first area. Assuming that the semiconductor chip is normally divided, these five areas are all areas containing 25 semiconductor chips with the first protective film arranged in 5 rows and 5 columns. In addition, these five areas are selected in the following manner: the first area exists in the approximate central part of the first line segment connecting the second area and the third area; the first area exists in the approximate central part of the second line segment connecting the fourth area and the fifth area; and the second area, the fourth area, the third area, and the fifth area are arranged in a clockwise direction. The first line segment is perpendicular to the second line segment. Then, these five areas are observed and the splitting of the semiconductor wafer is evaluated according to the following evaluation criteria.

[0530] Table 1 shows the results.

[0531] (Evaluation Criteria)

[0532] A: In all five regions (first region to fifth region), the semiconductor wafer is normally divided.

[0533] B: In at least one region (at least one region among the first to fifth regions), there is a portion where the semiconductor wafer is not normally divided.

[0534] <Evaluation of Cutting Properties of the First Protective Film>

[0535] When the above-mentioned semiconductor wafer splitting property was evaluated, the cutting property of the first protective film was evaluated according to the following evaluation criteria. The results are shown in Table 1.

[0536] (Evaluation Criteria)

[0537] A: In all five regions (first region to fifth region), the first protective film was cut normally.

[0538] B: In at least one region (at least one region among the first to fifth regions), there is a portion where the first protective film is not normally cut.

[0539] <Evaluation of Breaking Strength of First Protective Film>

[0540] A test thermosetting resin film (thickness 40 μm) was produced in the same manner as in the above-mentioned production of the thermosetting resin film except that the coating amount of the thermosetting resin layer-forming composition (III-1) was changed.

[0541] Next, the test thermosetting resin film was heated at 130° C. for 2 hours to be thermally cured.

[0542] Next, a piece having a size of 20 mm×130 mm was cut out from the cured product (ie, the first protective film) and used as a test piece.

[0543] A universal tensile tester (AUTOGRAPH AG-IS manufactured by Shimadzu Corporation) was used, the distance between the clamps was set to 80 mm, the tensile speed was set to 200 mm / min, the test piece was stretched in a direction parallel to its surface by the clamps, and the maximum stress of the test piece at this time was measured, and the maximum stress was used as the breaking strength of the first protective film. The results are shown in Table 1.

[0544] [Comparative Example 1]

[0545] <<Manufacturing of Thermosetting Resin Film and First Protective Film Forming Sheet>>

[0546] <Preparation of Thermosetting Resin Layer-Forming Composition>

[0547] The polymer component (A)-2 (10.0 parts by mass), epoxy resin (B1)-2 (30.0 parts by mass), epoxy resin (B1)-3 (33.0 parts by mass), thermosetting agent (B2)-1 (16.0 parts by mass), curing accelerator (C)-1 (0.2 parts by mass) and filler (D)-1 (11.0 parts by mass) were mixed, further diluted with methyl ethyl ketone, and stirred at 23° C. to prepare a resin layer forming composition having a total concentration of 55% by mass of the above six components except methyl ethyl ketone. These components and their contents are shown in Table 1.

[0548] <Manufacturing of Thermosetting Resin Film and First Protective Film Forming Sheet>

[0549] A thermosetting resin film and a first protective film-forming sheet were produced in the same manner as in Example 1 except that the composition obtained above was used as the resin layer-forming composition.

[0550] <<Manufacturing of semiconductor chip with first protective film>>

[0551] An attempt was made to manufacture a semiconductor chip with a first protective film (in other words, a sixth stacked structure) by the same method as in Example 1 except that the first protective film-forming sheet obtained above was used as the first protective film-forming sheet.

[0552] <<Evaluation of Thermosetting Resin Film and First Protective Film>>

[0553] The thermosetting resin film and the first protective film produced in this comparative example were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0554] [Comparative Example 2]

[0555] <<Manufacturing of Thermosetting Resin Film and First Protective Film Forming Sheet>>

[0556] <Preparation of Thermosetting Resin Layer-Forming Composition>

[0557] A polymer component (A)-3 (21.0 parts by mass), epoxy resin (B1)-4 (10.0 parts by mass), epoxy resin (B1)-5 (2.0 parts by mass), epoxy resin (B1)-6 (5.6 parts by mass), thermosetting agent (B2)-2 (0.5 parts by mass), curing accelerator (C)-1 (0.5 parts by mass), filler (D)-2 (6.0 parts by mass), filler (D)-3 (54.0 parts by mass), coupling agent (E)-1 (0.4 parts by mass) and colorant (I)-1 (1.9 parts by mass) were mixed, further diluted with methyl ethyl ketone, and stirred at 23° C. to prepare a resin layer forming composition having a total concentration of 55% by mass of the above 10 components except methyl ethyl ketone. These components and their contents are shown in Table 1.

[0558] <Manufacturing of Thermosetting Resin Film and First Protective Film Forming Sheet>

[0559] A thermosetting resin film and a first protective film-forming sheet were produced in the same manner as in Example 1 except that the composition obtained above was used as the resin layer-forming composition.

[0560] <<Manufacturing of semiconductor chip with first protective film>>

[0561] An attempt was made to manufacture a semiconductor chip with a first protective film (in other words, a sixth stacked structure) by the same method as in Example 1 except that the first protective film-forming sheet obtained above was used as the first protective film-forming sheet.

[0562] <<Evaluation of Thermosetting Resin Film and First Protective Film>>

[0563] The thermosetting resin film and the first protective film produced in this comparative example were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0564] [Table 1]

[0565]

[0566] As is clear from the above results, when the thermosetting resin film of Example 1 is attached to the bump formation surface of a semiconductor wafer, it is possible to suppress the thermosetting resin film from remaining on the top of the bumps, and thus it has a preferred characteristic.

[0567] The ratio of the total content of all kinds of thermosetting components in the thermosetting resin film of Example 1 to the total mass of the thermosetting resin film was 80.9 mass %.

[0568] Furthermore, in Example 1, the divisibility of the semiconductor wafer is good.

[0569] The light transmittance of the thermosetting resin film of Example 1 at a wavelength of 1342 nm is high. As a result, the light transmittance of the first protective film formed by the film is also high. When the semiconductor wafer is irradiated with laser through the first protective film, a modified layer can be well formed inside the semiconductor wafer.

[0570] Furthermore, in Example 1, the cutting property of the first protective film was good.

[0571] In Example 1, the total value of X value is 296 (={408×37.8 / (37.8+25.0+18.1)}+{265×25.0 / (37.8+25.0+18.1)}+{104×18.1 / (37.8+25.0+18.1)}) g / eq, and the breaking strength of the first protective film is 45 MPa.

[0572] In contrast, in Comparative Example 1, the first protective film has poor cutting properties.

[0573] In Comparative Example 1, the total value of X value is 524 (={265×30.0 / (30.0+33.0+16.0)}+{962×33.0 / (30.0+33.0+16.0)}+{104×16.0 / (30.0+33.0+16.0)}) g / eq, and the breaking strength of the first protective film is 60 MPa.

[0574] When the thermosetting resin film of Comparative Example 2 was attached to the bump-formed surface of a semiconductor wafer, it was not possible to suppress the thermosetting resin film from remaining on the top of the bumps, resulting in poor characteristics.

[0575] The ratio of the total content of all kinds of thermosetting components in the thermosetting resin film of Comparative Example 2 to the total mass of the thermosetting resin film was 17.8% by mass.

[0576] Furthermore, in Comparative Example 2, the divisibility of the semiconductor wafer was poor.

[0577] The light transmittance of the thermosetting resin film of Comparative Example 2 at a wavelength of 1342 nm was low, and as a result, the light transmittance of the first protective film formed by the film was also low. When the semiconductor wafer was irradiated with laser through the first protective film, a modified layer could not be properly formed inside the semiconductor wafer. As a result, the semiconductor wafer could not be normally divided.

[0578] For Comparative Example 2, the first protective film could not be cut, but it was not possible to determine to what extent the characteristics of the first protective film itself affected the result, so the cutting property of the first protective film could not be evaluated. However, since the fracture strength of the first protective film was as low as 25 MPa, it was speculated that the reason for not being able to cut the first protective film was mainly due to the poor splitting property of the semiconductor wafer.

[0579] Industrial Applicability

[0580] The present invention can be used to manufacture a workpiece having a protruding electrode on a connection pad portion used in a flip chip mounting method.

[0581] Description of Reference Numerals

[0582] 1, 2, 3: sheet for forming the first protective film; 11: first substrate; 11a: one surface of the first substrate; 12: thermosetting resin layer (thermosetting resin film); 12': first protective film; 120': first protective film after cutting; 13: first adhesive layer; 13a: one surface of the first adhesive layer; 14: first intermediate layer; 101, 102, 103: first supporting sheet; 101a, 102a, 103a: surface of the first supporting sheet; 206: sixth stacked structure; 90: workpiece; 90a: circuit surface of the workpiece; 91: convex electrode; 91a: surface of the convex electrode; 900: modified layer; 990: workpiece processed with the first protective film; R: laser.

Claims

1. A thermosetting resin film, which is a thermosetting resin film for forming a first protective film on a surface of a workpiece having a convex electrode by being attached to the surface and thermally cured, The thermosetting resin film contains a polymer component, two or more thermosetting components other than an acrylic resin having an epoxy group, and a filler. The polymer component is polyvinyl acetal, The thermosetting component is composed of bisphenol A type epoxy resin, dicyclopentadiene type epoxy resin and novolac type phenolic resin. The total content of all kinds of the thermosetting components in the thermosetting resin film is 80 to 90% by mass relative to the total mass of the thermosetting resin film. The content of the polymer component in the thermosetting resin film is 5 to 15% by mass relative to the total mass of the thermosetting resin film. The content of the filler in the thermosetting resin film is 5 to 15% by mass relative to the total mass of the thermosetting resin film. When the value of X calculated by the following formula is obtained for each type of the thermosetting component contained in the thermosetting resin film, and the total value of the values ​​of X of all types of the thermosetting components contained in the thermosetting resin film is obtained, the total value is 400 g / eq or less, X = [equivalent weight of the functional groups of the thermosetting component participating in the thermosetting reaction] × [content of the thermosetting component in the thermosetting resin film] / [total content of all types of thermosetting components in the thermosetting resin film], wherein the equivalent weight of the functional groups of the thermosetting component participating in the thermosetting reaction is expressed in g / eq, the content of the thermosetting component in the thermosetting resin film is expressed in parts by mass, and the total content of all types of thermosetting components in the thermosetting resin film is expressed in parts by mass. 2 . A first protective film-forming sheet comprising a first support sheet, wherein the thermosetting resin film according to claim 1 is provided on one surface of the first support sheet.

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