Semiconductor chip manufacturing method

Abstract

To provide a method for manufacturing a semiconductor chip that has excellent strength and restrains peeling of a protective film.SOLUTION: A method includes steps of: preparing a semiconductor chip fabrication wafer 10 having groove portions 13 as division-planed lines that are formed on a bump-forming surface 11a having bumps 12 of a semiconductor wafer 11 without reaching the rear surface of the semiconductor wafer; pressing and attaching a first curable resin x1 onto the bump-forming surface of the semiconductor chip fabrication wafer to cover the bump-forming surface of the semiconductor chip fabrication wafer with the first curable resin, and embedding the first curable resin in the groove portions formed in the semiconductor chip fabrication wafer; curing the first curable resin to obtain a semiconductor chip fabrication wafer with a first curable resin film; and dividing the semiconductor chip fabrication wafer with the first curable resin film into individual pieces along the division-planned lines to obtain semiconductor chips 40 in which at least bump-forming surfaces and side surfaces thereof are covered with a first curable resin film r1.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a semiconductor chip, and more particularly to a method for manufacturing a semiconductor chip in which a cured resin film is provided as a protective film. [Background technology]

[0002] In recent years, semiconductor devices have been manufactured using a mounting method known as the face-down method, in which a semiconductor chip having bumps on its circuit surface and a substrate for mounting the semiconductor chip are stacked together so that the circuit surface of the semiconductor chip faces the substrate, thereby mounting the semiconductor chip on the substrate. The semiconductor chips are usually obtained by dividing a semiconductor wafer having bumps on its circuit surface into individual chips.

[0003] A semiconductor wafer having bumps may be provided with a protective film for the purpose of protecting the bonded portion between the bump and the semiconductor wafer (hereinafter also referred to as a "bump neck"). For example, in Patent Documents 1 and 2, a laminate in which a supporting substrate, an adhesive layer, and a thermosetting resin layer are laminated in this order is pressed and attached to the bump-forming surface of a semiconductor wafer having bumps, with the thermosetting resin layer serving as the bonding surface, and then the thermosetting resin layer is heated and cured to form a protective film. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-092594 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-169484 Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, as electronic devices and other products incorporating ICs have become smaller and thinner, there has been a growing demand for thinner semiconductor chips. However, as semiconductor chips become thinner, their strength decreases. This can lead to problems such as semiconductor chips becoming more susceptible to breakage, for example, during transportation or during post-processing such as packaging. Therefore, it has been considered to form a protective film on the bump-forming surface of the semiconductor wafer to protect the bump necks and improve the strength of the semiconductor chip. However, simply forming a protective film on the bump-forming surface of the semiconductor wafer is not sufficient to improve the strength of the semiconductor chip. Furthermore, the protective film may peel off.

[0006] The present invention has been made in view of the above problems, and an object of the present invention is to provide a method for manufacturing a semiconductor chip that has excellent strength and in which peeling of the protective film is suppressed. [Means for solving the problem]

[0007] The inventors of the present invention came up with the idea that by providing a protective film, which is provided for the purpose of protecting bump necks, on the side surfaces of the semiconductor chip as well, it is possible to improve the strength of the semiconductor chip and also to suppress peeling of the protective film, thereby constructing an extremely rational configuration. As a result of extensive research based on this idea, they discovered a manufacturing method that can realize this idea, and have completed the present invention.

[0008] That is, the present invention relates to the following [1] to

[14] . [1] The method includes the following steps (S1) to (S4) in this order: Step (S1): A step of preparing a semiconductor chip manufacturing wafer having a bump-forming surface on which grooves as planned division lines are formed so as not to reach the rear surface of the semiconductor wafer. Step (S2): A step of pressing and pasting a first hardening resin (x1) onto the bump-formed surface of the semiconductor chip fabrication wafer, covering the bump-formed surface of the semiconductor chip fabrication wafer with the first hardening resin (x1), and embedding the first hardening resin (x1) in the grooves formed in the semiconductor chip fabrication wafer. Step (S3): A step of curing the first curable resin (x1) to obtain a wafer for producing semiconductor chips having a first curable resin film (r1). Step (S4): A step of dividing the semiconductor chip manufacturing wafer with the first cured resin film (r1) along the planned dividing lines to obtain semiconductor chips in which at least the bump-forming surface and side surfaces are covered with the first cured resin film (r1). The method for manufacturing a semiconductor chip further comprises the following step (S-BG) after the step (S2) and before the step (S3), after the step (S3) and before the step (S4), or in the step (S4): Step (S-BG): grinding the back surface of the semiconductor chip fabrication wafer. [2] The method for manufacturing a semiconductor chip described in [1] above, wherein the step (S2) is performed by pressing and attaching a first laminate (α1) having a laminate structure in which a first support sheet (Y1) and a layer (X1) of the first curable resin (x1) are laminated onto the bump formation surface of the semiconductor chip manufacturing wafer, with the layer (X1) serving as an attachment surface. [3] The step (S-BG) is included after the step (S2) and before the step (S3), the step (S-BG) is carried out by grinding the back surface of the semiconductor chip fabrication wafer with the first laminate (α1) attached, and then peeling the first support sheet (Y1) from the first laminate (α1); The method for manufacturing a semiconductor chip described in [2] above, wherein the step (S4) is carried out by cutting the portion of the first cured resin film (r1) of the semiconductor chip manufacturing wafer with the first cured resin film (r1) that is formed in the groove portion along the planned division line. [4] The step (S-BG) is included after the step (S3) and before the step (S4), The step (S3) is carried out without peeling the first support sheet (Y1) from the first laminate (α1), the step (S-BG) is carried out by grinding the back surface of the semiconductor chip fabrication wafer with the first laminate (α1) attached, and then peeling the first support sheet (Y1) from the first laminate (α1); The method for manufacturing a semiconductor chip described in [2] above, wherein the step (S4) is carried out by cutting the portion of the first cured resin film (r1) of the semiconductor chip manufacturing wafer with the first cured resin film (r1) that is formed in the groove portion along the planned division line. [5] The step (S-BG) is included after the step (S3) and before the step (S4), After the step (S2) and before the step (S3), the first support sheet (Y1) is peeled off from the first laminate (α1), the step (S-BG) is carried out by attaching a back-grinding sheet (b-BG) to the surface of the first cured resin film (r1) of the semiconductor chip production wafer having the first cured resin film (r1), grinding the back surface of the semiconductor chip production wafer with the back-grinding sheet (b-BG) attached, and then peeling the back-grinding sheet (b-BG) from the semiconductor chip production wafer having the first cured resin film (r1); The method for manufacturing a semiconductor chip described in [2] above, wherein the step (S4) is carried out by cutting the portion of the first cured resin film (r1) of the semiconductor chip manufacturing wafer with the first cured resin film (r1) that is formed in the groove portion along the planned division line. [6] The step (S-BG) is included in the step (S4), After the step (S2) and before the step (S3), the first support sheet (Y1) is peeled off from the first laminate (α1), The method for manufacturing a semiconductor chip described in [2] above, wherein the step (S4) is performed by making an incision along the planned dividing line in the portion of the first cured resin film (r1) of the semiconductor chip manufacturing wafer formed in the groove portion of the first cured resin film (r1) along the planned dividing line, or by forming a modified region along the planned dividing line, and then, in the step (S-BG), attaching a back-grinding sheet (b-BG) to the surface of the first cured resin film (r1) of the semiconductor chip manufacturing wafer formed with the first cured resin film (r1), and grinding the back surface of the semiconductor chip manufacturing wafer with the back-grinding sheet (b-BG) attached. [7] The method for producing a semiconductor chip according to any one of [1] to [6] above, further comprising the following step (T): Step (T): A step of forming a second cured resin film (r2) on the rear surface of the semiconductor chip fabrication wafer. [8] The method for producing a semiconductor chip according to any one of [1] to [7] above, further comprising the following step (U): Step (U): A step of removing the first cured resin film (r1) covering the top of the bump or the first cured resin film (r1) attached to a part of the top of the bump to expose the top of the bump. [9] The method for producing a semiconductor chip according to [8] above, wherein the step (U) is carried out by a plasma etching treatment.

[10] When a strain dispersion measurement is performed to measure the shear modulus G' of the test piece of the layer (X1) by generating a 400% strain on the test piece of the layer (X1) under the conditions of a temperature of 90°C and a frequency of 1 Hz, the shear modulus G' is 5.0 × 10 Pa to 1.0 × 10 6 The method for producing a semiconductor chip according to any one of the above [1] to [9], wherein Pa is

[11] The method for producing a semiconductor chip according to any one of the above [1] to

[10] , wherein the thickness of the layer (X1) is 10 μm or more and 200 μm or less.

[12] The method for manufacturing a semiconductor chip according to any one of the above [1] to

[11] , wherein the width of the groove is 10 μm to 2000 μm.

[13] The method for manufacturing a semiconductor chip according to any one of the above [1] to

[12] , wherein the depth of the groove is 30 μm to 700 μm.

[14] The method for producing a semiconductor chip according to any one of the above [1] to

[13] , wherein the first cured resin film (r1) is transparent. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a method for manufacturing a semiconductor chip that has excellent strength and in which peeling of the protective film is suppressed. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic diagram illustrating steps of a method for manufacturing a semiconductor chip according to the present invention. [Figure 2] FIG. 2 is a top view showing an example of a wafer for fabricating semiconductor chips prepared in step (S1). [Figure 3] 1 is a schematic cross-sectional view showing an example of a wafer for fabricating semiconductor chips prepared in step (S1). [Figure 4] FIG. 1 is a diagram showing an outline of step (S2). [Figure 5] 1A to 1C are diagrams illustrating an outline of a manufacturing method according to a first embodiment. [Figure 6] 10A to 10C are diagrams illustrating an outline of a manufacturing method according to a second embodiment. [Figure 7] 10A to 10C are diagrams illustrating an outline of a manufacturing method according to a third embodiment. [Figure 8] 10A to 10C are diagrams illustrating an outline of a manufacturing method according to a fourth embodiment. [Figure 9] FIG. 2 is a schematic cross-sectional view showing the structure of a first laminate (α1) used in the production method of the present invention. [Figure 10] FIG. 2 is a schematic cross-sectional view showing an example of a specific configuration of a first laminate (α1). [Figure 11] FIG. 10 is a schematic cross-sectional view showing another example of the specific configuration of the first laminate (α1). [Figure 12] FIG. 10 is a schematic cross-sectional view showing yet another example of the specific configuration of the first laminate (α1). [Figure 13] 1 is a photograph, substituted for a drawing, showing the results of rear surface observation in an example. [Figure 14] 1 is a photograph, substituted for a drawing, showing the results of cross-sectional polishing observation in an example. DETAILED DESCRIPTION OF THE INVENTION

[0011] In this specification, the term "active ingredient" refers to the components contained in the target composition, excluding diluent solvents such as water and organic solvents. In addition, in this specification, "(meth)acrylic acid" refers to both "acrylic acid" and "methacrylic acid", and the same applies to other similar terms. In this specification, the weight average molecular weight and number average molecular weight are values ​​measured by gel permeation chromatography (GPC) in terms of polystyrene. Furthermore, in this specification, for preferred numerical ranges (e.g., ranges of content, etc.), the lower and upper limits described in stages can be independently combined. For example, the description "preferably 10 to 90, more preferably 30 to 60" can be combined with the "preferable lower limit (10)" and the "more preferable upper limit (60)" to form "10 to 60."

[0012] [Method of manufacturing a semiconductor chip according to the present invention] FIG. 1 shows a schematic diagram of the steps of the method for producing a semiconductor chip of the present invention. The method for manufacturing semiconductor chips of the present invention roughly includes a step (S1) of preparing a wafer for semiconductor chip manufacturing, a step (S2) of attaching a first laminate (α1), a step (S3) of curing a first curable resin (x1), and a step (S4) of singulating, and further includes a step (S-BG) of grinding the back surface of the wafer for semiconductor chip manufacturing.

[0013] Specifically, the method for producing a semiconductor chip of the present invention includes the following steps (S1) to (S4) in this order. Step (S1): A step of preparing a semiconductor chip manufacturing wafer having a bump-forming surface on which grooves as planned division lines are formed so as not to reach the rear surface of the semiconductor wafer. Step (S2): A step of pressing and pasting a first hardening resin (x1) onto the bump-formed surface of the semiconductor chip fabrication wafer, covering the bump-formed surface of the semiconductor chip fabrication wafer with the first hardening resin (x1), and embedding the first hardening resin (x1) in the grooves formed in the semiconductor chip fabrication wafer. Step (S3): A step of curing the first curable resin (x1) to obtain a wafer for producing semiconductor chips having a first curable resin film (r1). Step (S4): A step of dividing the semiconductor chip manufacturing wafer with the first cured resin film (r1) along the planned dividing lines to obtain semiconductor chips in which at least the bump-forming surface and side surfaces are covered with the first cured resin film (r1). Furthermore, the method includes the following step (S-BG) after the step (S2) and before the step (S3), after the step (S3) and before the step (S4), or in the step (S4). Step (S-BG): grinding the back surface of the semiconductor chip fabrication wafer.

[0014] By using a manufacturing method including the above steps, a semiconductor chip can be obtained in which not only the bump-forming surface but also the side surfaces are covered with the first cured resin film (r1), which has excellent strength and is less likely to peel off as a protective film. The term "covered" here means that the first cured resin film (r1) is formed on at least the bump-forming surface and side surfaces of one semiconductor chip, following the shape of the semiconductor chip. In other words, the present invention is clearly different from encapsulation techniques that encapsulate multiple semiconductor chips in resin.

[0015] Each step of the method for manufacturing a semiconductor chip of the present invention will be described in detail below. In the following description, a "semiconductor chip" will also be referred to simply as a "chip," and a "semiconductor wafer" will also be referred to simply as a "wafer."

[0016] [Process (S1)] An example of the semiconductor wafer prepared in step (S1) is shown in a top view in FIG. 2 and a schematic cross-sectional view in FIG. In step (S1), a semiconductor chip manufacturing wafer 10 is prepared, in which grooves 13 serving as planned division lines are formed on the bump formation surface 11a of the semiconductor wafer 11 having bumps 12 thereon, without reaching the back surface 11b. Note that bumps are omitted from Fig. 2. Furthermore, in the drawings used in the following description, for the sake of convenience, in order to make the features of the present invention easier to understand, essential parts may be shown enlarged, and the dimensional ratios of each component may not necessarily be the same as in reality.

[0017] The shape of the bumps 12 is not particularly limited, and may be any shape as long as they can be brought into contact with and fixed to electrodes on a chip mounting substrate. 3, the bumps 12 are spherical, but the bumps 12 may be spheroids. The spheroids may be elongated in a direction perpendicular to the bump-forming surface 11a of the wafer 11, or may be elongated in a direction horizontal to the bump-forming surface 11a of the wafer 11. The bumps 12 may also be pillar-shaped.

[0018] The height of the bumps 12 is not particularly limited and may be changed as appropriate according to design requirements. For example, it is 30 μm to 300 μm, preferably 60 μm to 250 μm, and more preferably 80 μm to 200 μm. It should be noted that "the height of the bump 12" means the height of the portion of one bump that is located at the highest position from the bump-forming surface 11a.

[0019] The number of bumps 12 is not particularly limited either, and may be changed as appropriate according to design requirements.

[0020] The wafer 11 is a semiconductor wafer having circuits such as wiring, capacitors, diodes, and transistors formed on its surface. The material of the wafer is not particularly limited, and examples thereof include a silicon wafer, a silicon carbide wafer, a compound semiconductor wafer, a glass wafer, and a sapphire wafer.

[0021] The size of wafer 11 is not particularly limited, but from the viewpoint of improving batch processing efficiency, it is usually 8 inches (diameter 200 mm) or more, and preferably 12 inches (diameter 300 mm) or more. The shape of the wafer is not limited to a circle, and may be a polygonal shape such as a square or rectangle. In the case of a polygonal wafer, it is preferable that the length of the longest side of wafer 11 is equal to or greater than the above size (diameter) from the viewpoint of improving batch processing efficiency.

[0022] The thickness of the wafer 11 is not particularly limited, but is preferably 100 μm to 1,000 μm, more preferably 200 μm to 900 μm, and even more preferably 300 μm to 800 μm, from the viewpoint of easily suppressing warpage due to shrinkage when the first curable resin (x1) is cured and from the viewpoint of reducing the amount of grinding of the back surface 11b of the wafer 11 in a later step and thereby shortening the time required for back surface grinding.

[0023] A bump-forming surface 11a of a semiconductor chip fabrication wafer 10 prepared in step (S1) has a grid-like pattern of grooves 13 formed thereon as planned division lines for singulating the semiconductor chip fabrication wafer 10. The grooves 13 are notched grooves formed when applying a blade-tip dicing method (dicing before grinding), and are formed to a depth shallower than the thickness of the wafer 11 so that the deepest portions of the grooves 13 do not reach the back surface 11b of the wafer 11. The grooves 13 can be formed by dicing using a conventionally known wafer dicing device equipped with a dicing blade. The grooves 13 can also be formed by dicing using a laser or the like instead of a blade. The grooves 13 may be formed so that the semiconductor chip to be manufactured has a desired size and shape, and the grooves 13 do not necessarily have to be formed in a grid pattern as shown in Fig. 2. The size of a semiconductor chip is usually about 0.5 mm x 0.5 mm to 1.0 mm x 1.0 mm, but is not limited to this size.

[0024] From the viewpoint of improving the embedding property of the first curable resin (x1), the width of the groove 13 is preferably 10 μm to 2,000 μm, more preferably 50 μm to 1,000 μm, even more preferably 100 μm to 500 μm, and still more preferably 100 μm to 300 μm.

[0025] The depth of the groove 13 is adjusted depending on the thickness of the wafer used and the required chip thickness, and is preferably 30 μm to 700 μm, more preferably 60 μm to 600 μm, and even more preferably 100 μm to 500 μm.

[0026] The semiconductor chip fabrication wafer 10 prepared in the step (S1) is subjected to the step (S2).

[0027] [Process (S2)] An outline of step (S2) is shown in FIG. In the step (S2), a first hardening resin (x1) is pressed onto the bump formation surface 11a of the semiconductor chip fabrication wafer 10 to be attached thereto. Here, from the viewpoint of ease of handling of the first curable resin (x1), the first curable resin (x1) is preferably used by being laminated on the first support sheet (Y1). Therefore, in step (S2), it is preferable to press and attach a first laminate (α1) having a laminate structure in which a first support sheet (Y1) and a layer (X1) of a first curable resin (x1) are laminated onto the bump formation surface 11a of the semiconductor chip fabrication wafer 10, with the layer (X1) as the attachment surface. In step (S2), as shown in FIG. 4, the bump formation surface 11a of the semiconductor chip fabrication wafer 10 is covered with a first hardening resin (x1), and the first hardening resin (x1) is embedded in the grooves 13 formed in the semiconductor chip fabrication wafer 10.

[0028] By embedding the first curable resin (x1) in the grooves 13 formed in the semiconductor chip fabrication wafer 10, it is possible to coat with the first curable resin (x1) the portions that will become the side surfaces of the semiconductor chips when the semiconductor chip fabrication wafer 10 is singulated in step (S4). That is, a coating that serves as a precursor of the first cured resin film (r1) that coats the side surfaces of the semiconductor chips can be formed in step (S2), which is necessary to improve the strength of the semiconductor chips and to prevent peeling of the first cured resin film (r1) that serves as a protective film.

[0029] The pressure applied when attaching the first laminate (α1) to the semiconductor chip fabrication wafer 10 is preferably 1 kPa to 200 kPa, more preferably 5 kPa to 150 kPa, and even more preferably 10 kPa to 100 kPa, from the viewpoint of ensuring good embedding of the first curable resin (x1) into the grooves 13. The pressing force when attaching the first laminate (α1) to the semiconductor chip fabrication wafer 10 may be varied as appropriate from the beginning to the end of the attachment. For example, from the viewpoint of improving the embedding property of the first curable resin (x1) in the grooves 13, it is preferable to lower the pressing force at the beginning of the attachment and gradually increase the pressing force.

[0030] Furthermore, when the first laminate (α1) is attached to the semiconductor chip fabrication wafer 10, if the first curable resin (x1) is a thermosetting resin, it is preferable to heat the first curable resin (x1) from the viewpoint of improving the embeddability of the first curable resin (x1) in the grooves 13. If the first curable resin (x1) is a thermosetting resin, the fluidity of the first curable resin (x1) temporarily increases when heated, and the first curable resin (x1) hardens when heated continuously. Therefore, by heating within a range that improves the fluidity of the first curable resin (x1), the first curable resin (x1) can be more easily distributed throughout the entire grooves 13, and the embeddability of the first curable resin (x1) in the grooves 13 can be further improved. Specifically, the heating temperature (application temperature) is preferably 50°C to 150°C, more preferably 60°C to 130°C, and even more preferably 70°C to 110°C. The heat treatment performed on the first hardening resin (x1) is not included in the hardening treatment of the first hardening resin (x1).

[0031] Furthermore, when the first laminate (α1) is attached to the semiconductor chip fabrication wafer 10, it is preferable to do so in a reduced pressure environment. This creates a negative pressure in the grooves 13, making it easier for the first curable resin (x1) to spread throughout the entire grooves 13. As a result, the first curable resin (x1) is more easily embedded in the grooves 13. The specific pressure of the reduced pressure environment is preferably 0.001 kPa to 50 kPa, more preferably 0.01 kPa to 5 kPa, and even more preferably 0.05 kPa to 1 kPa.

[0032] The thickness of the layer (X1) of the first curable resin (x1) in the first laminate (α1) is preferably 10 μm or more, more preferably 20 μm or more, even more preferably 30 μm or more, and still more preferably more than 30 μm, from the viewpoint of further improving the embedding property of the first curable resin (x1) in the grooves 13. The thickness is preferably 200 μm or less, more preferably 150 μm or less, even more preferably 130 μm or less, still more preferably 100 μm or less, and even more preferably 80 μm or less. Here, "the thickness of the layer (X1) of the first curable resin (x1)" means the thickness of the entire layer (X1), and for example, the thickness of the layer (X1) consisting of multiple layers means the total thickness of all layers constituting the layer (X1).

[0033] Furthermore, from the viewpoint of further improving the embedding property of the first curable resin (x1) into the groove portion 13, the layer (X1) of the first curable resin (x1) is subjected to strain dispersion measurement in which a 400% strain is generated in a test piece of the layer (X1) under conditions of a temperature of 90°C and a frequency of 1 Hz, and the shear modulus G' of the test piece of the layer (X1) is measured. The shear modulus G' is preferably 5.0 × 10 Pa to 1.0 × 10 6 Pa, more preferably 1.0 × 10 2 Pa~1.0×10 5 Pa, more preferably 1.0 × 10 2 Pa~1.0×104 It is Pa. The shear modulus G' of the layer (X1) of the first curable resin (x1) is a value measured before the first curable resin (x1) is cured. The shear modulus G' can be adjusted by adjusting the composition of the first curable resin (x1).

[0034] Here, it is preferable that the first support sheet (Y1) of the first laminate (α1) not only supports the first curable resin (x1) but also functions as a backgrind sheet. In this case, when grinding the back surface 11b of the wafer 11 with the first laminate (α1) attached, the first support sheet (Y1) functions as a back grinding sheet, making it easier to carry out the back grinding process.

[0035] [Step (S3), Step (S4), and Step (S-BG)] The steps up to the step (S2) above form a laminate in which the first laminate (α1) is attached to the semiconductor chip fabrication wafer 10. This laminate is preferably subjected to any of the steps according to the first to fourth embodiments described below, depending on the timing of the implementation of the step (S-BG). Hereinafter, for the first to fourth embodiments, the steps (S3) and (S4) will be described, along with an explanation of the timing for performing the step (S-BG).

[0036] First Embodiment In the first embodiment, as shown in FIG. 1, step (S-BG) is performed after step (S2) and before step (S3). FIG. 5 shows a schematic diagram of the first embodiment.

[0037] (First embodiment: step (S-BG)) In the first embodiment, first, step (S-BG) is performed. Specifically, as shown in FIG. 5(1-a), the back surface 11b of the semiconductor chip fabrication wafer 10 is ground with the first laminate (α1) attached. "BG" in FIG. 5 means back grinding, and this also applies to the subsequent drawings. Next, as shown in FIG. 5(1-b), the first support sheet (Y1) is peeled off from the first laminate (α1). The amount of grinding when grinding the back surface 11b of the semiconductor chip fabrication wafer 10 should be an amount that exposes at least the bottom of the groove portion 13 of the semiconductor chip fabrication wafer 10, but further grinding may be performed so that the first curable resin (x1) embedded in the groove portion 13 is also ground together with the semiconductor chip fabrication wafer 10. In the first embodiment, since the first support sheet (Y1) is peeled off before performing step (S3), even if the first curable resin (x1) is a thermosetting resin and a heat treatment for curing is performed in step (S3), the first support sheet (Y1) does not need to be heat resistant, which increases the degree of freedom in designing the first support sheet (Y1).

[0038] (First embodiment: step (S3)) After the step (S-BG), the step (S3) is carried out. Specifically, as shown in FIG. 5 (1-c), the first curable resin (x1) is cured to obtain a semiconductor chip fabrication wafer 10 with a first cured resin film (r1). The first cured resin film (r1) formed by curing the first cured resin (x1) is stronger than the first cured resin (x1) at room temperature. Therefore, by forming the first cured resin film (r1), the bump necks are well protected. Furthermore, in step (S4) shown in FIG. 5 (1-d), the semiconductor chip fabrication wafer 10 with the first cured resin film (r1) is singulated to obtain semiconductor chips whose side surfaces are also covered with the first cured resin film (r1), resulting in semiconductor chips with excellent strength. Furthermore, peeling of the first cured resin film (r1) as a protective film is suppressed.

[0039] (First embodiment: curing method) The first curable resin (x1) can be cured by either heat curing or curing by irradiation with energy rays, depending on the type of curable component contained in the first curable resin (x1). In this specification, the term "energy rays" refers to electromagnetic waves or charged particle beams that have an energy quantum, and examples thereof include ultraviolet rays and electron beams, with ultraviolet rays being preferred. When thermal curing is carried out, the curing temperature is preferably 90° C. to 200° C., and the curing time is preferably 1 hour to 3 hours. The conditions for curing by energy ray irradiation are appropriately set depending on the type of energy ray used. For example, when ultraviolet rays are used, the illuminance is preferably 170 mW / cm 2 ~250mW / cm 2 and the light intensity is preferably 300 mJ / cm 2 ~3,000mJ / cm 2 is. Here, in the process of curing the first curable resin (x1) to form the first cured resin film (r1), the first curable resin (x1) is preferably a thermosetting resin from the viewpoint of removing air bubbles and the like that may be trapped when the groove portion 13 is filled with the first curable resin (x1) in step (S2). That is, when the first curable resin (x1) is a thermosetting resin, the fluidity of the first curable resin (x1) temporarily increases when heated, and the first curable resin (x1) hardens as the heating continues. By utilizing this phenomenon, when the fluidity of the first curable resin (x1) increases, air bubbles and the like that may be trapped when the groove portion 13 is filled with the first curable resin (x1) are removed, and the first curable resin (x1) can be cured after improving the embeddability of the first curable resin (x1) in the groove portion 13. From the viewpoint of shortening the curing time, the first curable resin (x1) is preferably an energy ray curable resin. The first curable resin (x1) for forming the first cured resin film (r1) will be described in detail later.

[0040] (First embodiment: step (S4)) After the step (S3), the step (S4) is carried out. Specifically, as shown in Fig. 5 (1-d), the portions of the first cured resin film (r1) of the semiconductor chip fabrication wafer 10 having the first cured resin film (r1) formed in the groove portions are cut along the planned division lines. The cutting can be carried out appropriately by adopting a conventionally known method such as blade dicing or laser dicing. As a result, it is possible to obtain a semiconductor chip 40 in which at least the bump-forming surface 11a and the side surfaces are covered with the first cured resin film (r1). The semiconductor chip 40 has excellent strength because the bump-forming surface 11a and side surfaces are coated with the first cured resin film (r1). Furthermore, because the bump-forming surface 11a and side surfaces are continuously and seamlessly coated with the first cured resin film (r1), the bonding surface (interface) between the bump-forming surface 11a and the first cured resin film (r1) is not exposed on the side surfaces of the semiconductor chip 40. The exposed portion of the bonding surface (interface) between the bump-forming surface 11a and the first cured resin film (r1) that is exposed on the side surfaces of the semiconductor chip 40 is likely to become the starting point for film peeling. Since the semiconductor chip 40 of the present invention does not have such an exposed portion, film peeling from the exposed portion is unlikely to occur during the process of cutting the semiconductor chip fabrication wafer 10 to manufacture the semiconductor chip 40 or after manufacture. Therefore, a semiconductor chip 40 can be obtained in which peeling of the first cured resin film (r1) serving as a protective film is suppressed.

[0041] In step (S4), when the portions of the first cured resin film (r1) of the semiconductor chip fabrication wafer 10 that are formed in the grooves are cut along the planned division lines, it is preferable that the first cured resin film (r1) is transparent. The transparency of the first cured resin film (r1) allows the semiconductor wafer 11 to be seen through, ensuring visibility of the planned division lines. This makes it easier to cut along the planned division lines.

[0042] Second Embodiment In the second embodiment, as shown in FIG. 1, step (S-BG) is performed after step (S3) and before step (S4). FIG. 6 shows a schematic diagram of the second embodiment.

[0043] (Second embodiment: step (S3)) In the second embodiment, first, step (S3) is performed. Specifically, as shown in Fig. 6 (2-a), the first curable resin (x1) is cured with the first laminate (α1) attached to obtain a semiconductor chip fabrication wafer 10 with a first cured resin film (r1) attached. The first cured resin film (r1) formed by curing the first cured resin (x1) is stronger than the first cured resin (x1) at room temperature. Therefore, by forming the first cured resin film (r1), the bump necks are well protected. Furthermore, by singulating the semiconductor chip fabrication wafer 10 with the first cured resin film (r1) in step (S4), semiconductor chips whose side surfaces are also covered with the first cured resin film (r1) can be obtained, resulting in semiconductor chips with excellent strength. Moreover, peeling of the first cured resin film (r1) as a protective film is also suppressed. The curing method may be the same as the curing method described in the first embodiment. By performing the thermal curing process without peeling off the first support sheet (Y1), it is possible to suppress the flow of the first curable resin (x1) on the surface that temporarily occurs when the first support sheet (Y1) hardens the first curable resin (x1) during thermal curing, and it is possible to improve the flatness of the first cured resin film (r1) on the bump formation surface. Furthermore, by curing the first curable resin (x1) before grinding the back surface 11b of the semiconductor chip fabrication wafer 10, warpage of the semiconductor chip fabrication wafer 10 is suppressed.

[0044] (Second embodiment: step (S-BG)) After the step (S3), the step (S-BG) is carried out. As shown in FIG. 6(2-b), the back surface 11b of the semiconductor chip fabrication wafer 10 is ground with the first laminate (α1) attached. The amount of grinding when grinding the back surface 11b of the semiconductor chip manufacturing wafer 10 should be an amount that exposes at least the bottom of the groove portion 13 of the semiconductor chip manufacturing wafer 10, but further grinding may be carried out so that the first cured resin film (r1) embedded in the groove portion 13 is also ground together with the semiconductor chip manufacturing wafer 10. Next, as shown in FIG. 6 (2-c), the first support sheet (Y1) is peeled off from the first laminate (α1).

[0045] (Second embodiment: step (S4)) After the step (S-BG), the step (S4) is carried out in the same manner as in the first embodiment. Specifically, as shown in Fig. 6 (2-d), the portions of the first cured resin film (r1) of the semiconductor chip fabrication wafer 10 having the first cured resin film (r1) formed in the groove portions are cut along the planned division lines. The cutting can be carried out appropriately by adopting a conventionally known method such as blade dicing or laser dicing. As a result, it is possible to obtain a semiconductor chip 40 in which at least the bump-forming surface 11a and the side surfaces are covered with the first cured resin film (r1). The semiconductor chip 40 has excellent strength because the bump-forming surface 11a and the side surfaces are covered with the first cured resin film (r1). Furthermore, for the reasons described above, the semiconductor chip 40 can be obtained in which peeling of the first cured resin film (r1) serving as a protective film is suppressed.

[0046] Third Embodiment The third embodiment is similar to the second embodiment in that step (S-BG) is performed after step (S3) and before step (S4), as shown in Fig. 1. However, the third embodiment differs from the second embodiment in that a back-grinding sheet (b-BG) is separately used. FIG. 7 shows a schematic diagram of the third embodiment.

[0047] (Third embodiment: step (S3)) In the third embodiment, first, step (S3) is performed. However, before that, as shown in FIG. 7(3-a), the first support sheet (Y1) is peeled off from the first laminate (α1). Then, step (S3) is performed. Specifically, as shown in FIG. 7(3-b), the first curable resin (x1) is cured to obtain a semiconductor chip fabrication wafer 10 with a first cured resin film (r1). The curing method may be the same as the curing method described in the first embodiment. Since the first support sheet (Y1) is peeled off before carrying out the step (S3), the first support sheet (Y1) does not need to be heat resistant even if the first curable resin (x1) is a thermosetting resin and a heat treatment for curing is carried out in the step (S3), which increases the degree of freedom in designing the first support sheet (Y1). Furthermore, by hardening the first hardening resin (x1) before grinding the back surface 11b of the semiconductor chip fabrication wafer 10, warpage of the semiconductor chip fabrication wafer 10 is suppressed.

[0048] (Third embodiment: step (S-BG)) After performing step (S3), step (S-BG) is performed. Specifically, as shown in FIG. 7(3-c), a back-grinding sheet (b-BG) is attached to the surface of the first cured resin film (r1) of the semiconductor chip fabrication wafer 10. Next, as shown in FIG. 7(3-d), the back surface 11b of the semiconductor chip fabrication wafer 10 is ground with the back-grinding sheet (b-BG) attached, and then, as shown in FIG. 7(3-e), the back-grinding sheet (b-BG) is peeled off from the semiconductor chip fabrication wafer 10 with the first cured resin film (r1). Since the back-grind sheet (b-BG) is not used in step (S3), even if the first curable resin (x1) is a thermosetting resin and a heat treatment is performed for curing in step (S3), the back-grind sheet (b-BG) does not require heat resistance, which increases the degree of freedom in designing the back-grind sheet (b-BG). The amount of grinding when grinding the back surface 11b of the semiconductor chip manufacturing wafer 10 should be an amount that exposes at least the bottom of the groove portion 13 of the semiconductor chip manufacturing wafer 10, but further grinding may be carried out so that the first cured resin film (r1) embedded in the groove portion 13 is also ground together with the semiconductor chip manufacturing wafer 10.

[0049] (Third embodiment: step (S4)) After the step (S-BG) is performed, the step (S4) is performed as in the first and second embodiments. Specifically, as shown in Fig. 7 (3-f), the portions of the first cured resin film (r1) of the semiconductor chip fabrication wafer 10 that are formed in the groove portions are cut along the planned division lines. The cutting can be carried out appropriately by adopting a conventionally known method such as blade dicing or laser dicing. As a result, it is possible to obtain a semiconductor chip 40 in which at least the bump-forming surface 11a and the side surfaces are covered with the first cured resin film (r1). The semiconductor chip 40 has excellent strength because the bump-forming surface 11a and the side surfaces are covered with the first cured resin film (r1). Furthermore, for the reasons described above, the semiconductor chip 40 can be obtained in which peeling of the first cured resin film (r1) serving as a protective film is suppressed.

[0050] <Fourth embodiment> In the fourth embodiment, as shown in FIG. 1, the step (S-BG) is performed in the step (S4). FIG. 8 shows a schematic diagram of the fourth embodiment.

[0051] (Fourth embodiment: step (S3)) In the fourth embodiment, first, step (S3) is performed. However, before that, as shown in FIG. 8 (4-a), the first support sheet (Y1) is peeled off from the first laminate (α1). Then, step (S3) is performed. Specifically, as shown in FIG. 8 (4-b), the first curable resin (x1) is cured to obtain a semiconductor chip fabrication wafer 10 with a first cured resin film (r1). The curing method may be the same as the curing method described in the first embodiment. Since the first support sheet (Y1) is peeled off before carrying out the step (S3), the first support sheet (Y1) does not need to be heat resistant even if the first curable resin (x1) is a thermosetting resin and a heat treatment for curing is carried out in the step (S3), which increases the degree of freedom in designing the first support sheet (Y1). Furthermore, by hardening the first hardening resin (x1) before grinding the back surface 11b of the semiconductor chip fabrication wafer 10, warpage of the semiconductor chip fabrication wafer 10 is suppressed.

[0052] (Fourth embodiment: step (S4) including step (S-BG)) After step (S3) is performed, as shown in FIG. 8 (4-c), incisions are made along the planned division lines in the portions of the first cured resin film (r1) of the semiconductor chip fabrication wafer 10 that are formed in the groove portions 13. From the viewpoint of facilitating singulation, it is preferable that the depth of the incisions be set to a depth that reaches the deepest portion of the groove portions 13. As a result, in step (S-BG) described below, the semiconductor chip fabrication wafer 10 that is provided with the first cured resin film (r1) is singulated along the incisions. Alternatively, although not shown, modified regions may be formed along the planned dividing lines in the portions of the first cured resin film (r1) of the semiconductor chip fabrication wafer 10 having the first cured resin film (r1) formed in the groove portions 13. The modified regions can be formed by laser or plasma treatment, etc. As a result, in step (S-BG) described below, cracks are generated starting from the modified regions, and the semiconductor chip fabrication wafer 10 having the first cured resin film (r1) is divided into individual pieces along the modified regions. Next, step (S-BG) is performed. Specifically, as shown in FIG. 8 (4-d), a backgrind sheet (b-BG) is attached to the surface of the first cured resin film (r1) of the semiconductor chip fabrication wafer 10 having the first cured resin film (r1). Next, as shown in FIG. 8 (4-e), the back surface 11b of the semiconductor chip fabrication wafer 10 is ground with the backgrind sheet (b-BG) attached. Finally, as shown in FIG. 8 (4-f), the backgrind sheet (b-BG) is peeled off from the semiconductor chip fabrication wafer 10 having the first cured resin film (r1). As a result, it is possible to obtain a semiconductor chip 40 in which at least the bump-forming surface 11a and the side surfaces are covered with the first cured resin film (r1). The amount of grinding when grinding the back surface 11b of the semiconductor chip manufacturing wafer 10 should be an amount that exposes at least the bottom of the groove portion 13 of the semiconductor chip manufacturing wafer 10, but further grinding may be carried out so that the first cured resin film (r1) embedded in the groove portion 13 is also ground together with the semiconductor chip manufacturing wafer 10. The semiconductor chip 40 has excellent strength because the bump-forming surface 11a and the side surfaces are covered with the first cured resin film (r1). Since the back-grind sheet (b-BG) is not used in step (S3), even if the first curable resin (x1) is a thermosetting resin and a heat treatment is performed for curing in step (S3), the back-grind sheet (b-BG) does not require heat resistance, which increases the degree of freedom in designing the back-grind sheet (b-BG).

[0053] Here, in the first to fourth embodiments, the first support sheet (Y1) or the back-grinding sheet (b-BG) is used in the step (S-BG) as described above. However, in one aspect of the present invention, a resin layer (Z1) for back-grinding may be formed instead of the first support sheet (Y1) or the back-grinding sheet (b-BG). Specifically, a fluid resin (z1) is used to coat the surface of the first cured resin film (r1) and also coat the bumps exposed from the first cured resin film (r1), and then the resin (z1) is hardened to form a resin layer (Z1) for back grinding, which can be used in place of a back grinding sheet to perform the grinding process. When the surface of the first cured resin film (r1) and the bumps exposed from the first cured resin film (r1) are coated with resin (z1), a flexible resin film (z2) capable of conforming to the unevenness of the bumps is used for coating, which makes it easier to peel off the resin layer (Z1) for back grinding that is no longer needed after the step (S-BG).

[0054] [Process (T)] In one aspect of the method for producing a semiconductor chip of the present invention, it is preferable to further include the following step (T). Step (T): A step of forming a second cured resin film (r2) on the rear surface of the semiconductor chip fabrication wafer.

[0055] According to the manufacturing method of the above embodiment, it is possible to obtain a semiconductor chip 40 in which at least the bump-forming surface 11a and the side surfaces are covered with the first cured resin film (r1). However, the back surface of the semiconductor chip 40 is exposed. Therefore, from the viewpoint of protecting the back surface of the semiconductor chip 40 and further improving the strength of the semiconductor chip 40, it is preferable to perform the above step (T).

[0056] More specifically, the above step (T) preferably includes the following steps (T1) to (T2) in this order. Step (T1): A step of attaching a second curable resin (x2) to the backside of a wafer for manufacturing semiconductor chips. Step (T2): A step of curing the second curable resin (x2) to form a second curable resin film (r2) In addition, in the step (T1), it is preferable to use a second laminate (α2) having a laminate structure in which a second support sheet (Y2) and a layer (X2) of a second curable resin (x2) are laminated. In detail, the step (T1) is preferably a step of attaching the second laminate (α2) having a laminate structure in which a second support sheet (Y2) and a layer (X2) of a second curable resin (x2) are laminated to the back surface of the semiconductor chip fabrication wafer, with the layer (X2) serving as an attachment surface. In this case, the timing for peeling off the second support sheet (Y2) from the second laminate (α2) may be between the step (T1) and the step (T2), or after the step (T2).

[0057] Here, when the second laminate (α2) is used in the step (T1), it is preferable that the second support sheet (Y2) of the second laminate (α2) not only supports the second curable resin (x2) but also functions as a dicing sheet. In the manufacturing methods of the first to third embodiments, in step (S4), the second laminate (α2) is attached to the back surface 11b of the semiconductor wafer 10 with the first cured resin film (r1), so that when dicing into individual pieces, the second support sheet (Y2) functions as a dicing sheet, making dicing easier to carry out.

[0058] Here, when step (S3) is performed after step (S-BG) as in the manufacturing method according to the first embodiment, step (T1) may be performed before step (S3), and then step (S3) and step (T2) may be performed simultaneously. That is, the first curable resin (x1) and the second curable resin (x2) may be cured simultaneously. This reduces the number of times the curing process is performed.

[0059] Specifically, in the production methods according to the first to third embodiments, the step (T) includes the following step (T1-1) and the following step (T1-2) in this order: Step (T1-1): After step (S-BG) and before step (S4), a step of attaching a second curable resin (x2) to the back surface of the semiconductor chip fabrication wafer. Step (T1-2): A step of curing the second curable resin (x2) to form a second cured resin film (r2) before or after step (S4). In step (S4), when cutting the portion of the first cured resin film (r1) formed in the groove portion of the semiconductor chip manufacturing wafer with the first cured resin film (r1) along the planned dividing line, it is preferable to also cut the second cured resin (x2) or the second cured resin film (r2) at the same time. In the production method according to the fourth embodiment, the step (T) includes the following step (T2-1) and the following step (T2-2) in this order: Step (T2-1): After step (S-BG) and after step (S4), a step of attaching a second curable resin (x2) to the back surface of the semiconductor chip fabrication wafer while the backgrind sheet (b-BG) remains attached. Step (T2-2): A step of curing the second curable resin (x2) to form a second cured resin film (r2) Furthermore, the step (T) preferably includes the following step (T2-3) before or after the step (T2-2). Step (T2-3): Step of dividing the second cured resin layer (x2) or the second cured resin film (r2) along the kerf

[0060] [Process (U)] One aspect of the method for producing a semiconductor chip of the present invention may further include the following step (U): Step (U): A step of removing the first cured resin film (r1) covering the top of the bump or the first cured resin film (r1) attached to a part of the top of the bump to expose the top of the bump. Examples of the exposure process for exposing the tops of the bumps include etching processes such as wet etching and dry etching. Here, the dry etching process may be, for example, a plasma etching process. If the tops of the bumps are not exposed on the surface of the protective film, the exposing process may be performed to recede the protective film until the tops of the bumps are exposed.

[0061] The timing of carrying out step (U) is not particularly limited as long as the first cured resin film (r1) is in an exposed state, and it is preferable that it is after step (S3) and before step (S4), when the first support sheet (Y1) and the backgrind sheet (b-BG) are not attached.

[0062] Next, the first laminate (α1) used in the semiconductor chip manufacturing method of one embodiment of the present invention will be described. Also, the back grinding sheet (b-BG) and the second laminate (α2) used in the semiconductor chip manufacturing method of one embodiment of the present invention will be described.

[0063] [Configuration of first laminate (α1)] An example of the structure of the first laminate (α1) used in the manufacturing method of one embodiment of the present invention is shown in FIG. The first laminate (α1) used in the manufacturing method of one embodiment of the present invention has a layer (X1) of a first curable resin (x1) provided on one surface of a first support sheet (Y1), like the first laminate (α1) shown in Fig. 9. By providing the layer (X1) of the first curable resin (x1) on one surface of the first support sheet (Y1), the layer (X1) of the first curable resin (x1) is stably supported and protected when the layer (X1) of the first curable resin (x1) is transported as a product package or when the layer (X1) of the first curable resin (x1) is conveyed in a process.

[0064] Specific structural examples of the first laminate (α1) are shown in FIGS. The first laminate (α1), like the first laminate (α1a) shown in Figure 10, has a first support sheet (Y1) as a base material 51, and a layer (X1) of a first curable resin (x1) is provided on one side of the base material 51. Furthermore, the first laminate (α1) may be, like the first laminate (α1b) shown in Figure 11, a first support sheet (Y1) which is an adhesive sheet formed by laminating a substrate 51 and an adhesive layer 61, and the adhesive layer 61 of the adhesive sheet may be bonded to a layer (X1) of a first curable resin (x1). Furthermore, the first laminate (α1) may be, like the first laminate (α1c) shown in FIG. 12, an adhesive sheet in which the first support sheet (Y1) is a substrate 51, an intermediate layer 71, and an adhesive layer 61 are laminated in this order, and the adhesive layer 61 of the adhesive sheet and the layer (X1) of the first curable resin (x1) may be bonded together. An adhesive sheet in which the substrate 51, the intermediate layer 71, and the adhesive layer 61 are laminated together in this order can be suitably used as a backgrinding tape. That is, the first laminate (α1c) shown in FIG. 12 has a backgrinding tape as the first support sheet (Y1), and therefore can be suitably used when grinding the backside of the semiconductor chip fabrication wafer to thin it after bonding the layer (X1) of the first curable resin (x1) of the first laminate (α1c) to the bump formation surface of the semiconductor chip fabrication wafer.

[0065] The first curable resin (x1) and the first support sheet (Y1) used in the first laminate (α1) will be described below.

[0066] <First hardening resin (x1)> The first curable resin (x1) is a film-like resin that covers the bump formation surface of the semiconductor chip fabrication wafer and is used to fill grooves formed in the semiconductor chip fabrication wafer, and forms a first cured resin film (r1) by curing with heat or energy ray irradiation. That is, the first curable resin (x1) may be a thermosetting resin film that is cured by heat (hereinafter also referred to as a "first thermosetting resin film (x1-1)"), or an energy ray-curable resin film that is cured by energy ray irradiation (hereinafter also referred to as a "first energy ray-curable resin film (x1-2)").

[0067] The physical properties of the first curable resin (x1) can be adjusted by adjusting either or both of the types and amounts of the components contained in the first curable resin (x1).

[0068] The first thermosetting resin film (x1-1) and the first energy ray-curable resin film (x1-2) will be described below.

[0069] <<First thermosetting resin film (x1-1)>> The first thermosetting resin film (x1-1) contains a polymer component (A) and a thermosetting component (B). The first thermosetting resin film (x1-1) is formed, for example, from a first thermosetting resin composition (x1-1-1) containing a polymer component (A) and a thermosetting component (B). The polymer component (A) is a component that can be considered to be formed by a polymerization reaction of a polymerizable compound. The thermosetting component (B) is a component that can undergo a curing (polymerization) reaction when triggered by heat. The curing (polymerization) reaction also includes a polycondensation reaction. In the following description of this specification, "the content of each component in the total amount of active ingredients of the first thermosetting resin composition (x1-1-1)" is synonymous with "the content of each component in the first thermosetting resin film (x1-1) formed from the first thermosetting resin composition (x1-1-1)."

[0070] (Polymer component (A)) The first thermosetting resin film (x1-1) and the first thermosetting resin composition (x1-1-1) contain a polymer component (A). The polymer component (A) is a polymer compound for imparting film-forming properties, flexibility, etc. to the first thermosetting resin film (x1-1). The polymer component (A) may be used alone or in combination of two or more. When two or more polymer components (A) are used in combination, the combination and ratio thereof can be selected arbitrarily.

[0071] Examples of the polymer component (A) include acrylic resins (resins having a (meth)acryloyl group), polyvinyl acetal, polyester, urethane resins (resins having a urethane bond), acrylic urethane resins, silicone resins (resins having a siloxane bond), rubber resins (resins having a rubber structure), phenoxy resins, and thermosetting polyimides. Among these, acrylic resins and polyvinyl acetals are preferred.

[0072] Examples of the acrylic resin include known acrylic polymers. From the viewpoint of making it easier to achieve the effects of the present invention, the weight average molecular weight (Mw) of the acrylic resin is preferably 10,000 to 2,000,000, more preferably 300,000 to 1,500,000, and even more preferably 500,000 to 1,000,000. When the weight-average molecular weight of the acrylic resin is equal to or greater than the lower limit, the shape stability (stability over time during storage) of the first thermosetting resin film (x1-1) is easily improved. Furthermore, when the weight-average molecular weight of the acrylic resin is equal to or less than the upper limit, the first thermosetting resin film (x1-1) is easily conformable to the uneven surface of the adherend, which makes it easier to suppress the occurrence of voids between the adherend and the first thermosetting resin film (x1-1). Therefore, it is easy to improve not only the coverage of the bump-forming surface 11a of the semiconductor wafer 11 but also the embedding ability into the grooves 13.

[0073] From the viewpoint of making it easier to exert the effects of the present invention, the glass transition temperature (Tg) of the acrylic resin is preferably from -60 to 70°C, more preferably from -40 to 50°C, and even more preferably from -30 to 30°C. When the glass transition temperature (Tg) of the acrylic resin is equal to or higher than the lower limit, the adhesive strength between the first cured resin film (r1) and the first support sheet (Y1) is suppressed, improving the peelability of the first support sheet (Y1). Furthermore, when the glass transition temperature (Tg) of the acrylic resin is equal to or lower than the upper limit, the adhesive strength between the first thermosetting resin film (x1-1) and the first cured resin film (r1) and the adherend is improved. Therefore, peeling of the first cured resin film (r1) as a protective film can be more easily prevented.

[0074] Examples of acrylic resins include polymers of one or more (meth)acrylic acid esters; copolymers of two or more monomers selected from (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N-methylolacrylamide.

[0075] Examples of the (meth)acrylic acid ester 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, and (meth) (meth)acrylic acid alkyl esters in which the alkyl group constituting the alkyl ester has a chain structure and has 1 to 18 carbon atoms, such as isononyl acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauryl (meth)acrylate), tridecyl (meth)acrylate, tetradecyl (meth)acrylate (myristyl (meth)acrylate), pentadecyl (meth)acrylate, hexadecyl (meth)acrylate (palmityl (meth)acrylate), heptadecyl (meth)acrylate, and octadecyl (meth)acrylate (stearyl (meth)acrylate); (meth)acrylic acid cycloalkyl esters such as isobornyl (meth)acrylate and dicyclopentanyl (meth)acrylate; (Meth)acrylic acid aralkyl esters such as benzyl (meth)acrylate; (Meth)acrylic acid cycloalkenyl esters such as (meth)acrylic acid dicyclopentenyl ester; (Meth)acrylic acid cycloalkenyloxyalkyl esters such as (meth)acrylic acid dicyclopentenyloxyethyl ester; (Meth)acrylic acid imide; glycidyl group-containing (meth)acrylic acid esters such as glycidyl (meth)acrylate; hydroxyl group-containing (meth)acrylic acid esters 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; Examples include substituted amino group-containing (meth)acrylic acid esters such as N-methylaminoethyl (meth)acrylate. As used herein, the term "substituted amino group" refers to a group in which one or two hydrogen atoms of an amino group have been substituted with a group other than a hydrogen atom. Among these, from the viewpoint of making it easier to exert the effects of the present invention, a copolymer of a (meth)acrylic acid alkyl ester, a glycidyl group-containing (meth)acrylic acid ester, and a hydroxyl group-containing (meth)acrylic acid ester, in which the alkyl group constituting the alkyl ester has a chain structure containing 1 to 18 carbon atoms, is preferred; a copolymer of a (meth)acrylic acid alkyl ester, a glycidyl group-containing (meth)acrylic acid ester, and a hydroxyl group-containing (meth)acrylic acid ester, in which the alkyl group constituting the alkyl ester has a chain structure containing 1 to 4 carbon atoms, is more preferred; and a copolymer of a combination of butyl acrylate, methyl acrylate, glycidyl acrylate, and 2-hydroxyethyl acrylate is even more preferred.

[0076] The acrylic resin may be, for example, a copolymer of one or more monomers selected from (meth)acrylic acid ester, (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, N-methylolacrylamide, and the like.

[0077] The monomer constituting the acrylic resin may be one type alone or two or more types. When the acrylic resin is composed of two or more types of monomers, the combination and ratio thereof can be selected arbitrarily.

[0078] The acrylic resin may have a functional group capable of bonding with other compounds, such as a vinyl group, a (meth)acryloyl group, an amino group, a hydroxyl group, a carboxyl group, or an isocyanate group. The functional group of the acrylic resin may be bonded to other compounds via a crosslinking agent (F) described below, or may be bonded directly to other compounds without the crosslinking agent (F). When the acrylic resin is bonded to other compounds via the functional group, the reliability of the package obtained using the first thermosetting resin film (x1-1) tends to be improved.

[0079] The polyvinyl acetal in the polymer component (A) may be any known polyvinyl acetal. Of these, preferred polyvinyl acetals include, for example, polyvinyl formal and polyvinyl butyral, with polyvinyl butyral being more preferred. Examples of polyvinyl butyral include those having structural units represented by the following formulas (i)-1, (i)-2, and (i)-3.

[0080] [ka] (In the formula, l, m, and n each independently represent an integer of 1 or more.)

[0081] The weight-average molecular weight (Mw) of the polyvinyl acetal is preferably 5,000 to 200,000, more preferably 8,000 to 100,000. When the weight-average molecular weight of the polyvinyl acetal is equal to or greater than the above-mentioned lower limit, the shape stability (stability over time during storage) of the first thermosetting resin film (x1-1) is easily improved. Furthermore, when the weight-average molecular weight of the polyvinyl acetal is equal to or less than the above-mentioned upper limit, the first thermosetting resin film (x1-1) is easily conformable to the uneven surface of the adherend, which makes it easier to suppress the occurrence of voids, for example, between the adherend and the first thermosetting resin film (x1-1). Therefore, not only is the coverage of the bump-forming surface 11a of the semiconductor wafer 11 improved, but the embedding of the grooves 13 is also easily improved.

[0082] The glass transition temperature (Tg) of the polyvinyl acetal is preferably 40 to 80°C, more preferably 50 to 70°C. When the Tg of the polyvinyl acetal is equal to or greater than the above lower limit, the adhesive strength between the first cured resin film (r1) and the first support sheet (Y1) is suppressed, improving the releasability of the first support sheet (Y1). When the Tg of the polyvinyl acetal is equal to or less than the above upper limit, the adhesive strength between the first thermosetting resin film (x1-1) and the first cured resin film (r1) and the adherend is improved. Therefore, peeling of the first cured resin film (r1) as a protective film can be more easily prevented.

[0083] The ratio of the three or more monomers constituting the polyvinyl acetal can be selected arbitrarily.

[0084] In one embodiment of the present invention, a thermoplastic resin other than an acrylic resin and a polyvinyl acetal (hereinafter, sometimes simply referred to as a "thermoplastic resin") may be used as the polymer component (A) either alone without using both an acrylic resin and a polyvinyl acetal, or in combination with one or both of an acrylic resin and a polyvinyl acetal. The use of a thermoplastic resin may improve the peelability of the first cured resin film (r1) from the first support sheet (Y1), or may facilitate conformance of the first thermosetting resin film (x1-1) to the uneven surface of the adherend, thereby further suppressing the occurrence of voids between the adherend and the first thermosetting resin film (x1-1). Therefore, it is easy to improve not only the coverage of the bump-forming surface 11a of the semiconductor wafer 11 but also the embedding ability into the grooves 13.

[0085] The weight average molecular weight of the thermoplastic resin is preferably 1,000 to 100,000, and more preferably 3,000 to 80,000.

[0086] The glass transition temperature (Tg) of the thermoplastic resin is preferably from -30 to 150°C, more preferably from -20 to 120°C.

[0087] Examples of thermoplastic resins include polyester, polyurethane, phenoxy resin, polybutene, polybutadiene, and polystyrene.

[0088] The thermoplastic resin may be used alone or in combination of two or more kinds. When two or more kinds of thermoplastic resins are used, the combination and ratio thereof can be selected arbitrarily.

[0089] The content of the polymer component (A) is preferably 5 to 85 mass %, more preferably 5 to 80 mass %, based on the total amount of active ingredients in the first thermosetting resin composition (x1-1-1).

[0090] The polymer component (A) may also correspond to the thermosetting component (B). In the present invention, when the first thermosetting resin composition (x1-1-1) contains components that correspond to both the polymer component (A) and the thermosetting component (B), the first thermosetting resin composition (x1-1-1) is considered to contain both the polymer component (A) and the thermosetting component (B).

[0091] (Thermosetting component (B)) The first thermosetting resin film (x1-1) and the first thermosetting resin composition (x1-1-1) contain a thermosetting component (B). The thermosetting component (B) is a component for curing the first thermosetting resin film (x1-1) to form a hard first cured resin film (r1). The thermosetting component (B) may be used singly or in combination of two or more. When two or more types of thermosetting component (B) are used, the combination and ratio thereof can be selected arbitrarily.

[0092] Examples of the thermosetting component (B) include epoxy-based thermosetting resins, thermosetting polyimides, polyurethanes, unsaturated polyesters, and silicone resins. Among these, epoxy-based thermosetting resins are preferred.

[0093] The epoxy thermosetting resin is composed of an epoxy resin (B1) and a thermosetting agent (B2). The epoxy thermosetting resin may be used alone or in combination of two or more. When two or more epoxy thermosetting resins are used, the combination and ratio thereof can be selected arbitrarily.

[0094] Epoxy resin (B1) Examples of the epoxy resin (B1) include known epoxy resins, such as polyfunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ether and its hydrogenated products, orthocresol novolac epoxy resins, dicyclopentadiene-type epoxy resins, biphenyl-type epoxy resins, bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, phenylene skeleton-type epoxy resins, and bifunctional or higher epoxy compounds. Among these, from the viewpoint of making it easier to exhibit the effects of the present invention, it is preferable to use polyfunctional epoxy resins, dicyclopentadiene-type epoxy resins, and bisphenol F-type epoxy resins. Furthermore, among polyfunctional epoxy resins, polyfunctional aromatic epoxy resins are preferable.

[0095] The epoxy resin (B1) may be an epoxy resin having an unsaturated hydrocarbon group. Epoxy resins having an unsaturated hydrocarbon group have higher compatibility with acrylic resins than epoxy resins not having an unsaturated hydrocarbon group. Therefore, by using an epoxy resin having an unsaturated hydrocarbon group, the reliability of the package obtained using the first thermosetting resin film (x1-1) is improved.

[0096] Examples of epoxy resins having unsaturated hydrocarbon groups include compounds obtained by converting some of the epoxy groups of a polyfunctional epoxy resin into groups having unsaturated hydrocarbon groups. Such compounds can be obtained, for example, by subjecting epoxy groups to an addition reaction with (meth)acrylic acid or a derivative thereof. Examples of epoxy resins having unsaturated hydrocarbon groups include compounds in which a group having an unsaturated hydrocarbon group is directly bonded to an aromatic ring or the like that constitutes the epoxy resin. The unsaturated hydrocarbon group is a polymerizable unsaturated group, and specific examples thereof include an ethenyl group (vinyl group), a 2-propenyl group (allyl group), a (meth)acryloyl group, and a (meth)acrylamide group. Among these, an acryloyl group is preferred.

[0097] The number average molecular weight of the epoxy resin (B1) is not particularly limited, but from the viewpoints of the curability of the first thermosetting resin film (x1-1) and the strength and heat resistance of the first cured resin film (r1) after curing, it is preferably 300 to 30,000, more preferably 400 to 10,000, and even more preferably 500 to 3,000. The epoxy equivalent of the epoxy resin (B1) is preferably 100 to 1,000 g / eq, more preferably 300 to 800 g / eq.

[0098] The epoxy resin (B1) may be used alone or in combination of two or more. When two or more epoxy resins (B1) are used in combination, the combination and ratio thereof can be selected arbitrarily.

[0099] Heat hardener (B2) The heat curing agent (B2) functions as a curing agent for the epoxy resin (B1). The thermosetting agent (B2) may be, for example, a compound having two or more functional groups per molecule that can react with an epoxy group. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group, and an anhydride group of an acid group. A phenolic hydroxyl group, an amino group, or an anhydride group of an acid group is preferred, and a phenolic hydroxyl group or an amino group is more preferred.

[0100] Among the heat curing agents (B2), examples of phenolic curing agents having a phenolic hydroxyl group include polyfunctional phenolic resins, biphenols, novolac-type phenolic resins, dicyclopentadiene-based phenolic resins, and aralkyl phenolic resins. Among the heat curing agents (B2), examples of amine-based curing agents having an amino group include dicyandiamide (hereinafter sometimes abbreviated as "DICY"). Among these, from the viewpoint of making it easier to exhibit the effects of the present invention, phenolic curing agents having a phenolic hydroxyl group are preferred, and novolac-type phenolic resins are more preferred.

[0101] The heat curing agent (B2) may have an unsaturated hydrocarbon group. Examples of the thermosetting agent (B2) having an unsaturated hydrocarbon group include a compound in which some of the hydroxyl groups of a phenolic resin are substituted with a group having an unsaturated hydrocarbon group, or a compound in which a group having an unsaturated hydrocarbon group is directly bonded to an aromatic ring of a phenolic resin. The unsaturated hydrocarbon group in the thermosetting agent (B2) is the same as the unsaturated hydrocarbon group in the epoxy resin having an unsaturated hydrocarbon group described above.

[0102] When a phenol-based curing agent is used as the thermosetting agent (B2), it is preferable that the thermosetting agent (B2) has a high softening point or glass transition temperature, in order to facilitate improving the peelability of the first cured resin film (r1) from the first support sheet (Y1).

[0103] Of the thermosetting agents (B2), for example, the number average molecular weight of resin components such as polyfunctional phenol resins, novolac-type phenol resins, dicyclopentadiene-based phenol resins, and aralkyl phenol resins is preferably 300 to 30,000, more preferably 400 to 10,000, and even more preferably 500 to 3,000. Of the thermosetting agent (B2), the molecular weight of the non-resin component such as biphenol or dicyandiamide is not particularly limited, but is preferably 60 to 500, for example.

[0104] The heat curing agent (B2) may be used singly or in combination of two or more. When two or more types of heat curing agents (B2) are used, the combination and ratio thereof can be selected arbitrarily.

[0105] In the first thermosetting resin composition (x1-1-1), the content of the thermosetting agent (B2) is preferably 0.1 to 500 parts by mass, and more preferably 1 to 200 parts by mass, per 100 parts by mass of the epoxy resin (B1). When the content of the thermosetting agent (B2) is equal to or greater than the above lower limit, curing of the first thermosetting resin film (x1-1) proceeds more easily. Furthermore, when the content of the thermosetting agent (B2) is equal to or less than the above upper limit, the moisture absorption rate of the first thermosetting resin film (x1-1) is reduced, and the reliability of the package obtained using the first thermosetting resin film (x1-1) is further improved.

[0106] In the first thermosetting resin composition (x1-1-1), the content of the thermosetting component (B) (total content of the epoxy resin (B1) and the thermosetting agent (B2)) is preferably 50 to 1,000 parts by mass, more preferably 100 to 900 parts by mass, and even more preferably 150 to 800 parts by mass, per 100 parts by mass of the content of the polymer component (A). When the content of the thermosetting component (B) is within this range, the adhesive strength between the first cured resin film (r1) and the first support sheet (Y1) is suppressed, and the releasability of the first support sheet (Y1) is improved.

[0107] (Curing accelerator (C)) The first thermosetting resin film (x1-1) and the first thermosetting resin composition (x1-1-1) may contain a curing accelerator (C). The curing accelerator (C) is a component for adjusting the curing rate of the first thermosetting resin composition (x1-1-1). Preferred examples of the curing accelerator (C) include tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol; imidazoles (imidazoles in which one or more hydrogen atoms are substituted with 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 substituted with organic groups) such as tributylphosphine, diphenylphosphine, and triphenylphosphine; and tetraphenylboron salts such as tetraphenylphosphonium tetraphenylborate and triphenylphosphine tetraphenylborate. Among these, imidazoles are preferred, and 2-phenyl-4,5-dihydroxymethylimidazole is more preferred, from the viewpoint of making it easier to exhibit the effects of the present invention.

[0108] The curing accelerator (C) may be used singly or in combination of two or more. When two or more curing accelerators (C) are used, the combination and ratio thereof can be selected arbitrarily.

[0109] When a curing accelerator (C) is used in the first thermosetting resin composition (x1-1-1), the content of the curing accelerator (C) is preferably 0.01 to 10 parts by mass, and more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the thermosetting component (B). When the content of the curing accelerator (C) is equal to or greater than the above lower limit, the effects of using the curing accelerator (C) are more pronounced. Furthermore, when the content of the curing accelerator (C) is equal to or less than the above upper limit, for example, the highly polar curing accelerator (C) is more effectively inhibited from migrating and segregating toward the adhesive interface with the adherend in the first thermosetting resin film (x1-1) under high temperature and high humidity conditions, thereby further improving the reliability of packages obtained using the first thermosetting resin film (x1-1).

[0110] (Filling material (D)) The first thermosetting resin film (x1-1) and the first thermosetting resin composition (x1-1-1) may contain a filler (D). The inclusion of the filler (D) makes it easier to adjust the thermal expansion coefficient of the first cured resin film (r1) obtained by curing the first thermosetting resin film (x1-1) within an appropriate range, thereby further improving the reliability of the package obtained using the first thermosetting resin film (x1-1). Furthermore, the inclusion of the filler (D) in the first thermosetting resin film (x1-1) can reduce the moisture absorption rate of the first cured resin film (r1) and improve the heat dissipation properties.

[0111] The filler (D) may be either an organic filler or an inorganic filler, but is preferably an inorganic filler. Preferred inorganic fillers include, for example, powders of silica, alumina, talc, calcium carbonate, titanium white, red iron oxide, silicon carbide, boron nitride, etc.; beads obtained by spheroidizing these inorganic fillers; surface-modified products of these inorganic fillers; single-crystal fibers of these inorganic fillers; glass fibers, etc. Among these, from the viewpoint of more easily achieving the effects of the present invention, the inorganic filler is preferably silica or alumina.

[0112] The filler (D) may be used alone or in combination of two or more kinds. When two or more types of filler (D) are used, the combination and ratio thereof can be selected arbitrarily.

[0113] When the filler (D) is used, the content of the filler (D) is preferably 5 to 80 mass %, more preferably 7 to 60 mass %, based on the total amount of the active ingredients of the first thermosetting resin composition (x1-1-1). When the content of the filler (D) is within this range, it becomes easier to adjust the thermal expansion coefficient.

[0114] The average particle diameter of the filler (D) is preferably 5 nm to 1000 nm, more preferably 5 nm to 500 nm, and even more preferably 10 nm to 300 nm. The average particle diameter is determined by measuring the outer diameter of a single particle at several points and calculating the average value.

[0115] (Coupling agent (E)) The first thermosetting resin film (x1-1) and the first thermosetting resin composition (x1-1-1) may contain a coupling agent (E). By using a coupling agent (E) having a functional group capable of reacting with an inorganic or organic compound, the adhesiveness and adhesion of the first thermosetting resin film (x1-1) and the first cured resin film (r1) to the substrate can be improved. Therefore, peeling of the first cured resin film (r1) as a protective film can be more easily suppressed. Furthermore, by using the coupling agent (E), the first cured resin film (r1) obtained by curing the first thermosetting resin film (x1-1) can be easily improved in water resistance without impairing heat resistance.

[0116] The coupling agent (E) is preferably a compound having a functional group capable of reacting with the functional groups of the polymer component (A) and the thermosetting component (B), and more preferably a silane coupling agent. Preferred silane coupling agents include, for example, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxymethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-(2-aminoethylamino) ... Examples of suitable silanes include 3-(triethoxysilylpropyl)triethoxysilane, 3-(phenylamino)propyltrimethoxysilane, 3-(phenylamino)propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, bis(3-triethoxysilylpropyl)tetrasulfane, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, and imidazole silane.

[0117] The coupling agent (E) may be used singly or in combination of two or more. When two or more coupling agents (E) are used, the combination and ratio thereof can be selected arbitrarily.

[0118] When a coupling agent (E) is used in the first thermosetting resin composition (x1-1-1), the content of the coupling agent (E) is preferably 0.03 to 20 parts by mass, more preferably 0.05 to 10 parts by mass, and even more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the total content of the polymer component (A) and the thermosetting component (B). When the content of the coupling agent (E) is at or above the lower limit, the effects of using the coupling agent (E), such as improved dispersibility of the filler (D) in the resin and improved adhesion of the first thermosetting resin film (x1-1) to an adherend, are more significantly obtained. Furthermore, when the content of the coupling agent (E) is at or below the upper limit, outgassing is further suppressed.

[0119] (Crosslinking agent (F)) When the polymer component (A) is one having a functional group such as a vinyl group, a (meth)acryloyl group, an amino group, a hydroxyl group, a carboxyl group, or an isocyanate group that can bond with other compounds, such as the above-mentioned acrylic resins, the first thermosetting resin film (x1-1) and the first thermosetting resin composition (x1-1-1) may contain a crosslinking agent (F) for bonding the functional group with other compounds to form crosslinks. By crosslinking using the crosslinking agent (F), the initial adhesive strength and cohesive strength of the first thermosetting resin film (x1-1) can be adjusted.

[0120] Examples of the crosslinking agent (F) include organic polyvalent isocyanate compounds, organic polyvalent imine compounds, metal chelate crosslinking agents (crosslinking agents having a metal chelate structure), and aziridine crosslinking agents (crosslinking agents having an aziridinyl group).

[0121] Examples of organic polyisocyanate compounds include aromatic polyisocyanate compounds, aliphatic polyisocyanate compounds, and alicyclic polyisocyanate compounds (hereinafter, these compounds may be collectively referred to as "aromatic polyisocyanate compounds, etc."); trimers, isocyanurates, and adducts of the aromatic polyisocyanate compounds, etc.; and isocyanate-terminated urethane prepolymers obtained by reacting the aromatic polyisocyanate compounds, etc. with polyol compounds. The "adduct" refers to a reaction product of the aromatic polyisocyanate compound, aliphatic polyisocyanate compound, or alicyclic polyisocyanate compound with a low-molecular-weight active hydrogen-containing compound such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, or castor oil, and examples thereof include the xylylene diisocyanate adduct of trimethylolpropane.

[0122] More specific examples of organic polyisocyanate compounds include 2,4-tolylene diisocyanate; 2,6-tolylene diisocyanate; 1,3-xylylene diisocyanate; 1,4-xylylene diisocyanate; diphenylmethane-4,4'-diisocyanate; diphenylmethane-2,4'-diisocyanate; 3-methyldiphenylmethane diisocyanate; hexamethylene diisocyanate; isophorone diisocyanate; dicyclohexylmethane-4,4'-diisocyanate; dicyclohexylmethane-2,4'-diisocyanate; compounds in which one or more of tolylene diisocyanate, hexamethylene diisocyanate, and xylylene diisocyanate are added to all or some of the hydroxyl groups of a polyol such as trimethylolpropane; lysine diisocyanate, and the like.

[0123] Examples of the organic polyvalent imine compound include N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide), trimethylolpropane-tri-β-aziridinylpropionate, tetramethylolmethane-tri-β-aziridinylpropionate, and N,N'-toluene-2,4-bis(1-aziridinecarboxamide)triethylenemelamine.

[0124] When an organic polyisocyanate compound is used as the crosslinking agent (F), it is preferable to use a hydroxyl group-containing polymer as the polymer component (A). When the crosslinking agent (F) has an isocyanate group and the polymer component (A) has a hydroxyl group, a crosslinked structure can be easily introduced into the first thermosetting resin film (x1-1) by the reaction between the crosslinking agent (F) and the polymer component (A).

[0125] The crosslinking agent (F) may be used singly or in combination of two or more. When two or more crosslinking agents (F) are used, the combination and ratio thereof can be selected arbitrarily.

[0126] When a crosslinking agent (F) is used in the first thermosetting resin composition (x1-1-1), the content of the crosslinking agent (F) is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 10 parts by mass, and even more preferably 0.5 to 5 parts by mass, per 100 parts by mass of the polymer component (A). When the content of the crosslinking agent (F) is equal to or greater than the lower limit, the effect of using the crosslinking agent (F) is more pronounced. Furthermore, when the content of the crosslinking agent (F) is equal to or less than the upper limit, excessive use of the crosslinking agent (F) is suppressed.

[0127] (Energy ray curable resin (G)) The first thermosetting resin film (x1-1) and the first thermosetting resin composition (x1-1-1) may contain an energy ray-curable resin (G). The first thermosetting resin film (x1-1) contains the energy ray-curable resin (G), and thus the properties can be changed by irradiation with energy rays.

[0128] The energy ray curable resin (G) is obtained by polymerizing (curing) an energy ray curable compound. 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.

[0129] Examples of acrylate compounds include chain acrylates 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-butylene glycol di(meth)acrylate, and 1,6-hexanediol di(meth)acrylate. Examples of the (meth)acrylate include aliphatic skeleton-containing (meth)acrylates; alicyclic skeleton-containing (meth)acrylates such as dicyclopentanyl 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 above-mentioned polyalkylene glycol (meth)acrylates; and itaconic acid oligomers.

[0130] The weight average molecular weight of the energy ray-curable compound is preferably from 100 to 30,000, and more preferably from 300 to 10,000.

[0131] The energy ray-curable compound used for polymerization may be used alone or in combination of two or more. When two or more energy ray-curable compounds are used for polymerization, the combination and ratio thereof can be selected arbitrarily.

[0132] When the energy ray curable resin (G) is used, the content of the energy ray curable resin (G) is preferably 1 to 95 mass%, more preferably 5 to 90 mass%, and even more preferably 10 to 85 mass%, based on the total amount of the active ingredients of the first thermosetting resin composition (x1-1-1).

[0133] (Photopolymerization initiator (H)) When the first thermosetting resin film (x1-1) and the first thermosetting resin composition (x1-1-1) contain an energy ray-curable resin (G), the first thermosetting resin film (x1-1) and the first thermosetting resin composition (x1-1-1) may contain a photopolymerization initiator (H) in order to efficiently proceed with the polymerization reaction of the energy ray-curable resin (G).

[0134] Examples of the photopolymerization initiator (H) include benzophenone, acetophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, benzoin methyl benzoate, benzoin dimethyl ketal, 2,4-diethylthioxanthone, 1-hydroxycyclohexyl phenyl ketone, benzyl diphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, benzyl, dibenzyl, diacetyl, 1,2-diphenylmethane, 2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and 2-chloroanthraquinone.

[0135] The first photopolymerization initiator (H) may be used singly or in combination of two or more. When two or more photopolymerization initiators (H) are used, the combination and ratio thereof can be selected arbitrarily.

[0136] In the first thermosetting resin composition (x1-1-1), the content of the photopolymerization initiator (H) is preferably 0.1 to 20 parts by mass, more preferably 1 to 10 parts by mass, and even more preferably 2 to 5 parts by mass, relative to 100 parts by mass of the content of the energy ray-curable resin (G).

[0137] (General-purpose additives (I)) The first thermosetting resin film (x1-1) and the first thermosetting resin composition (x1-1-1) may contain a general-purpose additive (I) within the range that does not impair the effects of the present invention. The general-purpose additive (I) may be a known additive and can be selected arbitrarily depending on the purpose, and is not particularly limited. Preferable general-purpose additives (I) include, for example, rheology control agents, surfactants, silicone oils, plasticizers, antistatic agents, antioxidants, and gettering agents.

[0138] The general-purpose additive (I) may be used singly or in combination of two or more. When two or more general-purpose additives (I) are used, the combination and ratio thereof can be selected arbitrarily. The content of the general-purpose additive (I) is not particularly limited and may be appropriately selected depending on the purpose.

[0139] The first thermosetting resin composition (x1-1-1) and the first thermosetting resin film (x1-1) may contain other components that do not fall under any of the above-mentioned polymer component (A), thermosetting component (B), curing accelerator (C), filler (D), coupling agent (E), crosslinking agent (F), energy ray-curable resin (G), photopolymerization initiator (H), and additive (I), as long as the effects of the present invention are not impaired. The other components contained in the first thermosetting resin composition (x1-1-1) and the first thermosetting resin film (x1-1) may be one type only, or two or more types. When there are two or more types, the combination and ratio thereof can be selected arbitrarily. The contents of the other components in the first thermosetting resin composition (x1-1-1) and the first thermosetting resin film (x1-1) are not particularly limited and may be appropriately selected depending on the purpose.

[0140] (solvent) The first thermosetting resin composition (x1-1-1) preferably further contains a solvent. The first thermosetting resin composition (x1-1-1) containing a solvent has good handleability. The solvent is not particularly limited, but preferred examples include hydrocarbons such as toluene and xylene; alcohols such as methanol, ethanol, 2-propanol, isobutyl alcohol (2-methylpropan-1-ol), and 1-butanol; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; and amides (compounds having an amide bond) such as dimethylformamide and N-methylpyrrolidone. The solvent may be used alone or in combination of two or more. When two or more solvents are used, the combination and ratio thereof can be selected arbitrarily. The solvent is preferably methyl ethyl ketone or the like, since this allows the components contained in the first thermosetting resin composition (x1-1-1) to be mixed more uniformly.

[0141] (Method for preparing first thermosetting resin composition (x1-1-1)) The first thermosetting resin composition (x1-1-1) is prepared by blending the components that constitute it. The order of addition of the components when blending is not particularly limited, and two or more components may be added simultaneously. When a solvent is used, the solvent may be mixed with any of the other components to pre-dilute the components, or the solvent may be mixed with any of the other components without pre-diluting them. The method for mixing the components during blending is not particularly limited, and may be appropriately selected from known methods such as a method of mixing by rotating a stirrer or stirring blades, a method of mixing using a mixer, or a method of mixing by adding ultrasound. The temperature and time for adding and mixing each component are not particularly limited as long as the components do not deteriorate, and may be adjusted appropriately. A temperature of 15 to 30°C is preferred.

[0142] <First energy ray curable resin film (x1-2)> The first energy ray-curable resin film (x1-2) contains an energy ray-curable component (a). The first energy ray-curable resin film (x1-2) is formed, for example, from a first energy ray-curable resin composition (x1-2-1) containing an energy ray-curable component (a). The energy ray-curable component (a) is preferably uncured and has adhesive properties, and more preferably uncured and has adhesive properties. In the following description of this specification, "the content of each component based on the total amount of active ingredients of the first energy ray-curable resin composition (x1-2-1)" is synonymous with "the content of each component of the first energy ray-curable resin film (x1-2) formed from the first energy ray-curable resin composition (x1-2-1)."

[0143] (Energy ray-curable component (a)) The energy ray-curable component (a) is a component that is cured by irradiation with energy rays, and is also a component that imparts film-forming properties, flexibility, and the like to the first energy ray-curable resin film (x1-2). Examples of the energy ray-curable component (a) include a polymer (a1) having an energy ray-curable group and a weight-average molecular weight of 80,000 to 2,000,000, and a compound (a2) having an energy ray-curable group and a molecular weight of 100 to 80,000. The polymer (a1) may be at least partially crosslinked with a crosslinking agent, or may not be crosslinked.

[0144] (Polymer (a1)) Examples of the polymer (a1) having an energy ray-curable group and a weight average molecular weight of 80,000 to 2,000,000 include an acrylic resin (a1-1) obtained by polymerizing an acrylic polymer (a11) having a functional group capable of reacting with a group possessed by another compound, and an energy ray-curable compound (a12) having a group reactive with the functional group and an energy ray-curable group such as an energy ray-curable double bond.

[0145] Examples of functional groups that can react with groups possessed by other compounds include hydroxyl groups, carboxyl groups, amino groups, substituted amino groups (groups in which one or two hydrogen atoms of an amino group are substituted with groups other than hydrogen atoms), and epoxy groups. However, from the viewpoint of preventing corrosion of circuits such as semiconductor wafers and semiconductor chips, it is preferable that the functional group be a group other than a carboxyl group. Among these, it is preferable that the functional group be a hydroxyl group.

[0146] Acrylic polymer having functional groups (a11) The acrylic polymer (a11) having a functional group may be, for example, a copolymer of an acrylic monomer having a functional group and an acrylic monomer not having a functional group, or may be a copolymer of these monomers with a monomer other than the acrylic monomer (non-acrylic monomer). The acrylic polymer (a11) may be a random copolymer or a block copolymer.

[0147] Examples of the acrylic monomer having a functional group include a hydroxyl group-containing monomer, a carboxy group-containing monomer, an amino group-containing monomer, a substituted amino group-containing monomer, and an epoxy group-containing monomer.

[0148] Examples of hydroxyl group-containing monomers include hydroxyalkyl (meth)acrylates such as hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; and non-(meth)acrylic unsaturated alcohols (unsaturated alcohols not having a (meth)acryloyl skeleton) such as vinyl alcohol and allyl alcohol.

[0149] Examples of carboxy group-containing monomers include ethylenically unsaturated monocarboxylic acids (monocarboxylic acids having an ethylenically unsaturated bond) such as (meth)acrylic acid and crotonic acid; ethylenically unsaturated dicarboxylic acids (dicarboxylic acids having an ethylenically unsaturated bond) such as fumaric acid, itaconic acid, maleic acid and citraconic acid; anhydrides of the above ethylenically unsaturated dicarboxylic acids; and (meth)acrylic acid carboxyalkyl esters such as 2-carboxyethyl methacrylate.

[0150] The acrylic monomer having a functional group is preferably a hydroxyl group-containing monomer or a carboxyl group-containing monomer, and more preferably a hydroxyl group-containing monomer.

[0151] The acrylic monomer having a functional group that constitutes the acrylic polymer (a11) may be used alone or in combination of two or more. When the acrylic polymer (a11) contains two or more types of acrylic monomers having a functional group, the combination and ratio thereof can be selected arbitrarily.

[0152] Examples of acrylic monomers having no functional group include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, and isopropyl (meth)acrylate. Examples of (meth)acrylic acid alkyl esters include those in which the alkyl group constituting the alkyl ester has a chain structure and has 1 to 18 carbon atoms, such as nonyl, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauryl (meth)acrylate), tridecyl (meth)acrylate, tetradecyl (meth)acrylate (myristyl (meth)acrylate), pentadecyl (meth)acrylate, hexadecyl (meth)acrylate (palmityl (meth)acrylate), heptadecyl (meth)acrylate, and octadecyl (meth)acrylate (stearyl (meth)acrylate).

[0153] Examples of acrylic monomers having no functional group include (meth)acrylic acid esters having an alkoxyalkyl group, such as methoxymethyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxymethyl (meth)acrylate, and ethoxyethyl (meth)acrylate; (meth)acrylic acid esters having an aromatic group, including (meth)acrylic acid aryl esters, such as phenyl (meth)acrylate; non-crosslinkable (meth)acrylamide and derivatives thereof; and (meth)acrylic acid esters having a non-crosslinkable tertiary amino group, such as N,N-dimethylaminoethyl (meth)acrylate and N,N-dimethylaminopropyl (meth)acrylate.

[0154] The acrylic monomer having no functional group that constitutes the acrylic polymer (a11) may be used alone or in combination of two or more. When the acrylic polymer (a11) contains two or more types of acrylic monomers having no functional group, the combination and ratio thereof can be selected arbitrarily.

[0155] Examples of non-acrylic monomers include olefins such as ethylene and norbornene; vinyl acetate; and styrene.

[0156] The non-acrylic monomer constituting the acrylic polymer (a11) may be used singly or in combination of two or more. When the acrylic polymer (a11) is composed of two or more non-acrylic monomers, the combination and ratio thereof can be selected arbitrarily.

[0157] In the acrylic polymer (a11), the proportion (content) of the amount of structural units derived from acrylic monomers having functional groups relative to the total mass of the structural units constituting the acrylic polymer (a11) is preferably 0.1 to 50 mass%, more preferably 1 to 40 mass%, and even more preferably 3 to 30 mass%. When the proportion is within this range, the content of energy ray-curable groups in the acrylic resin (a1-1) obtained by copolymerization of the acrylic polymer (a11) and the energy ray-curable compound (a12) can easily adjust the degree of curing of the first cured resin film (r1) within a preferred range.

[0158] The acrylic polymer (a11) constituting the acrylic resin (a1-1) may be used singly or in combination of two or more. When the acrylic polymer (a11) constituting the acrylic resin (a1-1) is two or more types, the combination and ratio thereof can be selected arbitrarily.

[0159] The content of the acrylic resin (a1-1) is preferably 1 to 60 mass%, more preferably 3 to 50 mass%, and even more preferably 5 to 40 mass%, based on the total amount of active ingredients of the first energy ray-curable resin composition (x1-2-1).

[0160] Energy ray curable compounds (a12) The energy ray-curable compound (a12) preferably has one or more groups selected from the group consisting of an isocyanate group, an epoxy group, and a carboxy group as a group reactive with the functional group of the acrylic polymer (a11), and more preferably has an isocyanate group as the group. When the energy ray-curable compound (a12) has, for example, an isocyanate group as the group, this isocyanate group readily reacts with the hydroxyl group of the acrylic polymer (a11) having a hydroxyl group as the functional group.

[0161] The energy ray-curable compound (a12) preferably has 1 to 5 energy ray-curable groups, and more preferably 1 or 2 energy ray-curable groups in one molecule.

[0162] Examples of the energy ray-curable compound (a12) include 2-methacryloyloxyethyl isocyanate, meta-isopropenyl-α,α-dimethylbenzyl isocyanate, methacryloyl isocyanate, allyl isocyanate, 1,1-(bisacryloyloxymethyl)ethyl isocyanate; an acryloyl monoisocyanate compound obtained by reacting a diisocyanate compound or a polyisocyanate compound with hydroxyethyl (meth)acrylate; and an acryloyl monoisocyanate compound obtained by reacting a diisocyanate compound or a polyisocyanate compound with a polyol compound and hydroxyethyl (meth)acrylate. Among these, the energy ray-curable compound (a12) is preferably 2-methacryloyloxyethyl isocyanate.

[0163] The energy ray-curable compound (a12) constituting the acrylic resin (a1-1) may be used alone or in combination of two or more. When the energy ray-curable compound (a12) constituting the acrylic resin (a1-1) is two or more types, the combination and ratio thereof can be selected arbitrarily.

[0164] In the acrylic resin (a1-1), the ratio of the content of the energy ray-curable groups derived from the energy ray-curable compound (a12) to the content of the functional groups derived from the acrylic polymer (a11) is preferably 20 to 120 mol%, more preferably 35 to 100 mol%, and even more preferably 50 to 100 mol%. When the content ratio is within this range, the adhesive strength of the first cured resin film (r1) after curing is increased. Therefore, peeling of the first cured resin film (r1) as a protective film can be more easily suppressed. When the energy ray-curable compound (a12) is a monofunctional compound (having one such group per molecule), the upper limit of the content ratio is 100 mol%. However, when the energy ray-curable compound (a12) is a polyfunctional compound (having two or more such groups per molecule), the upper limit of the content ratio may exceed 100 mol%.

[0165] The weight average molecular weight (Mw) of the polymer (a1) is preferably from 100,000 to 2,000,000, and more preferably from 300,000 to 1,500,000.

[0166] When the polymer (a1) is at least partially crosslinked with a crosslinking agent, the polymer (a1) may be one which is obtained by polymerizing a monomer which does not correspond to any of the above-mentioned monomers described as constituting the acrylic polymer (a11) and has a group which reacts with the crosslinking agent, and which is crosslinked at the group which reacts with the crosslinking agent, or may be one which is derived from the energy ray-curable compound (a12) and which is crosslinked at a group which reacts with the functional group.

[0167] The polymer (a1) may be used singly or in combination of two or more. When two or more types of polymer (a1) are used, the combination and ratio thereof can be selected arbitrarily.

[0168] (Compound (a2)) The energy ray-curable group contained in the compound (a2) having an energy ray-curable group and a weight average molecular weight of 100 to 80,000 includes a group containing an energy ray-curable double bond, and preferred examples thereof include a (meth)acryloyl group or a vinyl group.

[0169] The compound (a2) is not particularly limited as long as it satisfies the above conditions, and examples thereof include a low-molecular-weight compound having an energy ray-curable group, an epoxy resin having an energy ray-curable group, and a phenolic resin having an energy ray-curable group.

[0170] Among the compounds (a2), examples of low molecular weight compounds having an energy ray-curable group include polyfunctional monomers or oligomers, and acrylate compounds having a (meth)acryloyl group are preferred. Examples of the acrylate compounds include 2-hydroxy-3-(meth)acryloyloxypropyl methacrylate, polyethylene glycol di(meth)acrylate, propoxylated ethoxylated bisphenol A di(meth)acrylate, 2,2-bis[4-((meth)acryloxypolyethoxy)phenyl]propane, ethoxylated bisphenol A di(meth)acrylate, 2,2-bis[4-((meth)acryloxydiethoxy)phenyl]propane, 9,9-bis[4-(2-(meth)acryloyloxyethoxy)phenyl]fluorene, 2,2-bis[4-((meth)acryloxypolypropoxy)phenyl]propane, tricyclodecane dimethanol di(meth)acrylate, 1,10-decanediol ... bifunctional (meth)acrylates such as 6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, 2,2-bis[4-((meth)acryloxyethoxy)phenyl]propane, neopentyl glycol di(meth)acrylate, ethoxylated polypropylene glycol di(meth)acrylate, and 2-hydroxy-1,3-di(meth)acryloxypropane;Examples of the polyfunctional (meth)acrylates include tris(2-(meth)acryloxyethyl)isocyanurate, ε-caprolactone-modified tris-(2-(meth)acryloxyethyl)isocyanurate, ethoxylated glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol poly(meth)acrylate, and dipentaerythritol hexa(meth)acrylate; and polyfunctional (meth)acrylate oligomers such as urethane (meth)acrylate oligomers.

[0171] Of the compounds (a2), examples of epoxy resins having an energy ray-curable group and phenolic resins having an energy ray-curable group that can be used include those described in paragraph 0043 of JP 2013-194102 A.

[0172] The compound (a2) preferably has a weight average molecular weight of 100 to 30,000, more preferably 300 to 10,000.

[0173] The compound (a2) may be used singly or in combination of two or more. When two or more compounds (a2) are used, the combination and ratio thereof can be selected arbitrarily.

[0174] (Polymer (b) having no energy ray-curable group) When the first energy ray-curable resin composition (x1-2-1) and the first energy ray-curable resin film (x1-2) contain the compound (a2) as the energy ray-curable component (a), it is preferable that they also contain a polymer (b) that does not have an energy ray-curable group. The polymer (b) having no energy ray-curable group may be at least partially crosslinked with a crosslinking agent, or may not be crosslinked.

[0175] Examples of the polymer (b) having no energy ray-curable group include acrylic polymers, phenoxy resins, urethane resins, polyesters, rubber-based resins, and acrylic urethane resins. Among these, the polymer (b) is preferably an acrylic polymer (hereinafter sometimes abbreviated as "acrylic polymer (b-1)").

[0176] The acrylic polymer (b-1) may be a known polymer, for example, a homopolymer of one acrylic monomer, or a copolymer of two or more acrylic monomers. Alternatively, the acrylic polymer (b-1) may be a copolymer of one or more acrylic monomers and one or more monomers other than the acrylic monomers (non-acrylic monomers).

[0177] Examples of the acrylic monomer constituting the acrylic polymer (b-1) include (meth)acrylic acid alkyl esters, (meth)acrylic acid esters having a cyclic skeleton, glycidyl group-containing (meth)acrylic acid esters, hydroxyl group-containing (meth)acrylic acid esters, and substituted amino group-containing (meth)acrylic acid esters.

[0178] Examples of (meth)acrylic acid alkyl esters include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, and isononyl (meth)acrylate. Examples of the alkyl (meth)acrylate include alkyl (meth)acrylates in which the alkyl group constituting the alkyl ester has a chain structure and has 1 to 18 carbon atoms, such as ethyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauryl (meth)acrylate), tridecyl (meth)acrylate, tetradecyl (meth)acrylate (myristyl (meth)acrylate), pentadecyl (meth)acrylate, hexadecyl (meth)acrylate (palmityl (meth)acrylate), heptadecyl (meth)acrylate, and octadecyl (meth)acrylate (stearyl (meth)acrylate).

[0179] Examples of (meth)acrylic acid esters having a cyclic skeleton include (meth)acrylic acid cycloalkyl esters such as isobornyl (meth)acrylate and dicyclopentanyl (meth)acrylate; (meth)acrylic acid aralkyl esters such as benzyl (meth)acrylate; (meth)acrylic acid cycloalkenyl esters such as dicyclopentenyl (meth)acrylate; and (meth)acrylic acid cycloalkenyloxyalkyl esters such as dicyclopentenyloxyethyl (meth)acrylate.

[0180] Examples of the glycidyl group-containing (meth)acrylic acid ester include glycidyl (meth)acrylate, etc. Examples of the hydroxyl group-containing (meth)acrylic acid ester include hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. Examples of the substituted amino group-containing (meth)acrylic acid ester include N-methylaminoethyl (meth)acrylate.

[0181] Examples of non-acrylic monomers that constitute the acrylic polymer (b-1) include olefins such as ethylene and norbornene; vinyl acetate; and styrene.

[0182] The polymer (b) having no energy ray-curable group and at least a portion of which is crosslinked with a crosslinking agent may be, for example, a polymer in which a reactive functional group in the polymer (b) has reacted with a crosslinking agent. The reactive functional group is not particularly limited and may be appropriately selected depending on the type of crosslinking agent, etc. For example, when the crosslinking agent is a polyisocyanate compound, examples of the reactive functional group include a hydroxyl group, a carboxyl group, and an amino group, and among these, a hydroxyl group is preferred because of its high reactivity with an isocyanate group. When the crosslinking agent is an epoxy compound, examples of the reactive functional group include a carboxy group, an amino group, and an amide group, and among these, a carboxy group is preferred because it has high reactivity with an epoxy group. However, from the viewpoint of preventing corrosion of the circuits of semiconductor wafers and semiconductor chips, it is preferable that the reactive functional group is a group other than a carboxy group.

[0183] Examples of the polymer (b) having a reactive functional group but not having an energy ray-curable group include those obtained by polymerizing at least a monomer having a reactive functional group. In the case of the acrylic polymer (b-1), any one or both of the acrylic monomers and non-acrylic monomers listed as the constituent monomers may be used that have a reactive functional group. For example, examples of the polymer (b) having a hydroxyl group as a reactive functional group include those obtained by polymerizing a hydroxyl group-containing (meth)acrylic acid ester, and other examples include those obtained by polymerizing a monomer in which one or more hydrogen atoms in the acrylic monomer or non-acrylic monomer listed above are substituted with the reactive functional group.

[0184] In the polymer (b) having a reactive functional group, the proportion (content) of the amount of the structural units derived from the monomer having a reactive functional group relative to the total mass of the structural units constituting the polymer (b) is preferably 1 to 20 mass%, more preferably 2 to 10 mass%. When the proportion is in this range, the degree of crosslinking in the polymer (b) becomes a more preferable range.

[0185] The weight average molecular weight (Mw) of the polymer (b) having no energy ray-curable group is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1,500,000, in order to improve the film-forming properties of the first energy ray-curable resin composition (x1-2-1).

[0186] The polymer (b) having no energy ray-curable group may be used alone or in combination of two or more. When the polymer (b) having no energy ray-curable group is used in two or more types, the combination and ratio thereof can be selected arbitrarily.

[0187] The first energy ray-curable resin composition (x1-2-1) may contain one or both of a polymer (a1) and a compound (a2). When the first energy ray-curable resin composition (x1-2-1) contains the compound (a2), it is preferable that it further contains a polymer (b) that does not have an energy ray-curable group, and in this case, it is also preferable that it further contains a polymer (a1). Alternatively, the first energy ray-curable resin composition (x1-2-1) may not contain the compound (a2) but may contain both the polymer (a1) and the polymer (b) having no energy ray-curable group.

[0188] When the first energy ray-curable resin composition (x1-2-1) contains the polymer (a1), the compound (a2), and the polymer (b) that does not have an energy ray-curable group, the content of the compound (a2) is preferably 10 to 400 parts by mass, and more preferably 30 to 350 parts by mass, per 100 parts by mass of the total content of the polymer (a1) and the polymer (b) that does not have an energy ray-curable group.

[0189] The total content of the energy ray-curable component (a) and the polymer (b) having no energy ray-curable group is preferably 5 to 90 mass%, more preferably 10 to 80 mass%, and even more preferably 20 to 70 mass%, based on the total amount of active ingredients of the first energy ray-curable resin composition (x1-2-1). When the content of the energy ray-curable component is within this range, the energy ray curability of the first energy ray-curable resin film (x1-2) becomes better.

[0190] The first energy ray-curable resin composition (x1-2-1) may contain, in addition to the energy ray-curable component, one or more selected from the group consisting of a thermosetting component, a curing accelerator, a photopolymerization initiator, a filler, a coupling agent, a crosslinking agent, and a general-purpose additive, depending on the purpose. For example, by using a first energy ray-curable resin composition (x1-2-1) containing an energy ray-curable component and a thermosetting component, the formed first energy ray-curable resin film (x1-2) has improved adhesive strength to an adherend upon heating, and the strength of the first cured resin film (r1) formed from this first energy ray-curable resin film (x1-2) is also improved.

[0191] The thermosetting component, photopolymerization initiator, filler, coupling agent, crosslinking agent, and general-purpose additives in the first energy ray-curable resin composition (x1-2-1) may be the same as the thermosetting component (B), curing accelerator (C), photopolymerization initiator (H), filler (D), coupling agent (E), crosslinking agent (F), and general-purpose additive (I) in the first thermosetting resin composition (x1-1-1), respectively.

[0192] In the first energy ray-curable resin composition (x1-2-1), the thermosetting component, photopolymerization initiator, filler, coupling agent, crosslinking agent, and general-purpose additive may each be used alone or in combination of two or more. When two or more are used in combination, the combination and ratio thereof can be selected arbitrarily. The contents of the thermosetting component, photopolymerization initiator, filler, coupling agent, crosslinking agent, and general-purpose additive in the first energy ray-curable resin composition (x1-2-1) may be appropriately adjusted depending on the purpose, and are not particularly limited.

[0193] The first energy ray-curable resin composition (x1-2-1) preferably further contains a solvent, since dilution improves its handleability. Examples of the solvent contained in the first energy ray-curable resin composition (x1-2-1) include the same solvents as those in the first thermosetting resin composition (x1-1-1). The solvent contained in the first energy ray-curable resin composition (x1-2-1) 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 can be selected arbitrarily.

[0194] (Other ingredients) The first energy ray-curable resin composition (x1-2-1) and the first energy ray-curable resin film (x1-2) may contain other components that do not fall under any of the above-mentioned components, as long as the effects of the present invention are not impaired. The other components contained in the first energy ray-curable resin composition (x1-2-1) and the first energy ray-curable resin film (x1-2) may be one type only or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily. The contents of the other components in the first energy ray-curable resin composition (x1-2-1) and the first energy ray-curable resin film (x1-2) are not particularly limited and may be appropriately selected depending on the purpose.

[0195] (Method for producing first energy ray-curable resin composition (x1-2-1)) The first energy ray-curable resin composition (x1-2-1) can be obtained by blending the components that constitute it. The order in which the components are added when blending them is not particularly limited, and two or more components may be added simultaneously. When a solvent is used, the solvent may be mixed with any of the other ingredients to dilute the ingredients before use, or the solvent may be mixed with any of the other ingredients without pre-diluting them. The method for mixing the ingredients during blending is not particularly limited, and may be appropriately selected from known methods such as a method of mixing by rotating a stirrer or stirring blades, a method of mixing using a mixer, or a method of mixing by applying ultrasound. The temperature and time for adding and mixing each component are not particularly limited as long as the components do not deteriorate, and may be adjusted appropriately. A temperature of 15 to 30°C is preferred.

[0196] <First support sheet (Y1)> The first support sheet (Y1) functions as a support for supporting the first curable resin (x1). The first support sheet (Y1) may be composed of only a substrate 51 as shown in Fig. 10, or may be a laminate of a substrate 51 and an adhesive layer 61 as shown in Fig. 11, or may be a laminate in which a substrate 51, an intermediate layer 71, and an adhesive layer 61 are laminated in this order as shown in Fig. 12. A laminate in which a substrate 51, an intermediate layer 71, and an adhesive layer 61 are laminated in this order is suitable for use as a backgrind sheet (b-BG).

[0197] The substrate of the first support sheet (Y1), and the pressure-sensitive adhesive layer and intermediate layer that the first support sheet (Y1) may have will be described below.

[0198] (base material) The substrate is in the form of a sheet or film, and examples of the constituent materials thereof include the following various resins. Examples of resins constituting the substrate include polyethylenes such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and high-density polyethylene (HDPE); polyolefins other than polyethylene such as polypropylene, polybutene, polybutadiene, polymethylpentene, and norbornene resin; ethylene-based copolymers (copolymers obtained using ethylene as a monomer) such as ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester copolymer, and ethylene-norbornene copolymer; and vinyl chloride-based resins (copolymers obtained using vinyl chloride as a monomer) such as polyvinyl chloride and vinyl chloride copolymer. resins obtained by the above method); polystyrene; polycycloolefin; polyesters such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyethylene isophthalate, polyethylene-2,6-naphthalenedicarboxylate, and wholly aromatic polyesters in which all structural units have aromatic cyclic groups; copolymers of two or more of the above polyesters; poly(meth)acrylic acid esters; polyurethanes; polyurethane acrylates; polyimides; polyamides; polycarbonates; fluororesins; polyacetals; modified polyphenylene oxides; polyphenylene sulfides; polysulfones; and polyether ketones. Further, examples of the resin constituting the substrate include polymer alloys such as mixtures of the polyester and other resins. The polymer alloys of the polyester and other resins preferably contain a relatively small amount of resin other than polyester. Further, examples of the resin constituting the substrate include crosslinked resins in which one or more of the resins exemplified above are crosslinked; and modified resins such as ionomers using one or more of the resins exemplified above.

[0199] The resin constituting the substrate may be one type used alone or two or more types used in combination. When the substrate is composed of two or more types of resins, the combination and ratio thereof can be selected arbitrarily.

[0200] The substrate may be one layer (single layer) or two or more layers. When the substrate is a multilayer substrate, these layers may be the same or different from each other, and the combination of these layers is not particularly limited.

[0201] The thickness of the substrate is preferably 5 μm to 1,000 μm, more preferably 10 μm to 500 μm, even more preferably 15 μm to 300 μm, and even more preferably 20 μm to 150 μm. Here, the "thickness of the substrate" means the thickness of the entire substrate, and for example, the thickness of a substrate consisting of multiple layers means the total thickness of all layers that make up the substrate.

[0202] The substrate preferably has a high thickness precision, i.e., a thickness variation that is suppressed regardless of location. Among the above-mentioned constituent materials, examples of materials with a high thickness precision that can be used to constitute the substrate include polyethylene, polyolefins other than polyethylene, polyethylene terephthalate, and ethylene-vinyl acetate copolymer.

[0203] In addition to the main constituent materials such as the resin, the substrate may contain various known additives such as fillers, colorants, antistatic agents, antioxidants, organic lubricants, catalysts, and softeners (plasticizers).

[0204] The substrate may be transparent or opaque, may be colored depending on the purpose, or may have other layers vapor-deposited thereon. When the first curable resin film (x1) is the first energy ray-curable resin film (x1-2) and when the pressure-sensitive adhesive layer is an energy-curable pressure-sensitive adhesive layer, the substrate is preferably one that transmits energy rays.

[0205] The substrate can be produced by a known method. For example, a substrate containing a resin can be produced by molding a resin composition containing the resin.

[0206] (Adhesive layer) The pressure-sensitive adhesive layer is in the form of a sheet or film and contains a pressure-sensitive adhesive. Examples of adhesives include adhesive resins such as acrylic resins (adhesives made of resins having (meth)acryloyl groups), urethane resins (adhesives made of resins having urethane bonds), rubber resins (adhesives made of resins having a rubber structure), silicone resins (adhesives made of resins having siloxane bonds), epoxy resins (adhesives made of resins having epoxy groups), polyvinyl ethers, polycarbonates, etc. Among these, acrylic resins are preferred.

[0207] In the present invention, the term "adhesive resin" is a concept that includes both a resin having adhesive properties and a resin having adhesive properties, and includes, for example, not only resins that are adhesive in themselves, but also resins that become adhesive when used in combination with other components such as additives, and resins that become adhesive in the presence of a trigger such as heat or water.

[0208] The pressure-sensitive adhesive layer may be one layer (single layer) or two or more layers. When the pressure-sensitive adhesive layer is a multi-layer structure, these layers may be the same or different from each other, and the combination of these layers is not particularly limited.

[0209] The thickness of the pressure-sensitive adhesive layer is preferably 1 μm to 1000 μm, more preferably 5 μm to 500 μm, and even more preferably 10 μm to 100 μm. Here, the "thickness of the pressure-sensitive adhesive layer" refers to the thickness of the entire pressure-sensitive adhesive layer, and for example, the thickness of a pressure-sensitive adhesive layer consisting of multiple layers refers to the total thickness of all layers that make up the pressure-sensitive adhesive layer.

[0210] The pressure-sensitive adhesive layer may be formed using an energy ray-curable pressure-sensitive adhesive or a non-energy ray-curable pressure-sensitive adhesive. The pressure-sensitive adhesive layer formed using an energy ray-curable pressure-sensitive adhesive can easily adjust its physical properties before and after curing.

[0211] <Middle class> The intermediate layer is in the form of a sheet or film, and its constituent material may be appropriately selected depending on the purpose and is not particularly limited. For example, when the purpose is to prevent the first cured resin film (r1) from being deformed by the shape of bumps present on the semiconductor surface being reflected in the protective film covering the semiconductor surface, a preferred constituent material for the intermediate layer is urethane (meth)acrylate, etc., because it has high conformability to irregularities and further improves the adhesion of the intermediate layer.

[0212] The intermediate layer may be one layer (single layer) or two or more layers. When the intermediate layer is a multi-layer structure, these multiple layers may be the same or different from each other, and the combination of these multiple layers is not particularly limited.

[0213] The thickness of the intermediate layer can be adjusted appropriately depending on the height of the bumps on the semiconductor surface to be protected, but is preferably 50 μm to 600 μm, more preferably 70 μm to 500 μm, and even more preferably 80 μm to 400 μm, so as to easily absorb the effects of relatively tall bumps. Here, the "thickness of the intermediate layer" refers to the thickness of the entire intermediate layer; for example, the thickness of an intermediate layer consisting of multiple layers refers to the total thickness of all the layers that make up the intermediate layer.

[0214] Next, a method for producing the first laminate (α1) will be described.

[0215] [Method for producing first laminate (α1)] The first laminate (α1) can be produced by laminating the above-mentioned layers in order so that they are in a corresponding positional relationship. For example, when manufacturing the first support sheet (Y1), if a pressure-sensitive adhesive layer or an intermediate layer is laminated on a substrate, the pressure-sensitive adhesive composition or a composition for forming an intermediate layer can be applied to the substrate, and if necessary, dried or irradiated with energy rays, thereby laminating the pressure-sensitive adhesive layer or intermediate layer. Examples of the coating method include spin coating, spray coating, bar coating, knife coating, roll coating, roll knife coating, blade coating, die coating, and gravure coating.

[0216] On the other hand, for example, when a first curable resin film (x1) is laminated on top of a pressure-sensitive adhesive layer already laminated on a substrate, the first thermosetting resin composition (x1-1-1) or the first energy ray-curable resin composition (x1-2-1) can be applied onto the pressure-sensitive adhesive layer to directly form the first curable resin (x1). Similarly, when a pressure-sensitive adhesive layer is laminated on an intermediate layer already laminated on a substrate, the pressure-sensitive adhesive composition can be applied onto the intermediate layer to directly form the pressure-sensitive adhesive layer.

[0217] Thus, when forming a continuous two-layer laminate structure using any of the compositions, it is possible to form a new layer by applying another composition on the layer formed from the composition. However, it is preferable that the layer to be laminated later is first formed on a separate release film using the composition, and the exposed surface of this formed layer opposite the side in contact with the release film is bonded to the exposed surface of the remaining layer already formed to form a continuous two-layer laminate structure. In this case, it is preferable that the composition is applied to the release-treated surface of the release film. The release film can be removed as needed after the laminate structure is formed.

[0218] [Second laminate (α2)] The second laminate (α2) is not particularly limited as long as it has a configuration that allows a protective film to be formed on the back surface of a semiconductor wafer, and for example, the same configuration as the first laminate (α1) can be adopted. Therefore, the second hardening resin (x2) contained in the second laminate (α2) may be made of the same material and have the same structure as the first hardening resin (x1).

[0219] (Colorant (J)) Here, from the viewpoint of improving the visibility of the markings formed by laser marking, and from the viewpoint of improving the design of the semiconductor chip by making grinding marks on the back surface of the semiconductor chip less visible, it is preferable that the second curable resin (x2) and the second curable resin-forming composition for forming the second curable resin (x2) contain a colorant (J). Examples of the colorant (J) include known ones such as inorganic pigments, organic pigments, and organic dyes. Examples of the organic pigments and organic dyes include aminium-based dyes, cyanine-based dyes, merocyanine-based dyes, croconium-based dyes, squarium-based dyes, azulenium-based dyes, polymethine-based dyes, naphthoquinone-based dyes, pyrylium-based dyes, phthalocyanine-based dyes, naphthalocyanine-based dyes, naphtholactam-based dyes, azo-based dyes, condensed azo-based dyes, indigo-based dyes, perinone-based dyes, perylene-based dyes, dioxazine-based dyes, quinacridone-based dyes, isoindolinone-based dyes, quinophthalone-based dyes, pyrrole-based dyes, thioindigo-based dyes, metal complex-based dyes (metal complex dyes), dithiol metal complex-based dyes, indolephenol-based dyes, triallylmethane-based dyes, anthraquinone-based dyes, naphthol-based dyes, azomethine-based dyes, benzimidazolone-based dyes, pyranthrone-based dyes, and threne-based dyes. Examples of the inorganic pigments include carbon black, cobalt-based pigments, iron-based pigments, chromium-based pigments, titanium-based pigments, vanadium-based pigments, zirconium-based pigments, molybdenum-based pigments, ruthenium-based pigments, platinum-based pigments, ITO (indium tin oxide)-based pigments, and ATO (antimony tin oxide)-based pigments.

[0220] The colorant (J) contained in the second curable resin (x2) and the second curable resin-forming composition for forming the second curable resin (x2) may be one type or two or more types. When two or more types of colorant (J) are used, the combination and ratio thereof can be selected arbitrarily. When a colorant (J) is used, the content of the colorant (J) in the second curable resin film (x2) may be adjusted appropriately depending on the purpose. For example, as described above, the second cured resin film (r2), which is a cured product formed by curing the second curable resin (x2), may be printed by laser irradiation. By adjusting the content of the colorant (J) in the second curable resin (x2) and adjusting the light transmittance of the protective film, the visibility of the print can be adjusted. Furthermore, adjusting the content of the colorant (J) can improve the design of the protective film and make grinding marks on the backside of the semiconductor wafer less visible. Considering these points, in the second curable resin-forming composition for forming the second curable resin film (x2), the ratio of the content of the colorant (J) to the total content of all components other than the solvent (also referred to as the total mass of the solids in the second curable resin film-forming composition) (i.e., the content of the colorant (J) in the second curable resin (x2)) is preferably 0.1 to 10 mass%, more preferably 0.1 to 7.5 mass%, and particularly preferably 0.1 to 5 mass%. When the content of the colorant (J) is equal to or greater than the lower limit, the effect of using the colorant (J) is more pronounced. Furthermore, when the content of the colorant (J) is equal to or less than the upper limit, an excessive decrease in the light transmittance of the second curable resin (x2) is suppressed.

[0221] The first curable resin (x1) and the first curable resin-forming composition may also contain a colorant (J). However, from the viewpoint of ensuring the visibility of the dividing lines of the semiconductor chip fabrication wafer, the content of the colorant (J) is preferably within a range that ensures a level of transparency that ensures the visibility of the dividing lines.

[0222] The second support sheet (Y2) of the second laminate (α2) may have the same configuration as the first support sheet (Y1). Specifically, like the first support sheet (Y1), the second support sheet (Y2) may be composed of only a substrate 51 as shown in Fig. 10, or may be an adhesive sheet in which a substrate 51 and an adhesive layer 61 are laminated as shown in Fig. 11, or may be an adhesive sheet in which a substrate 51, an intermediate layer 71, and an adhesive layer 61 are laminated as shown in Fig. 12. The substrate, intermediate layer, and adhesive layer of the second support sheet (Y2) may have the same configuration and materials as the substrate, intermediate layer, and adhesive layer of the first support sheet (Y1). [Example]

[0223] The present invention will be specifically described with reference to the following examples, but the present invention is not limited to these examples.

[0224] 1. Preparation of wafers for semiconductor chip fabrication A 12-inch silicon wafer (775 μm thick) was used as the wafer for semiconductor chip fabrication, with the planned dividing lines cut in half. The width of the half-cut portion of the silicon wafer (the width of the groove) was 200 μm, and the depth of the groove was 200 μm.

[0225] 2. Apply the first hardening resin (x1) A first laminate (α1) consisting of a backgrind tape ("E-8510HR" manufactured by Lintec Corporation) and a 90 μm thick layer (X1) of a first curable resin (x1) was laminated as a first support sheet (Y1) on the front side (half-cut forming surface) of a semiconductor chip manufacturing wafer, and was pressed and attached under the following conditions with the first curable resin (x1) side as the attachment surface. - Application device: Fully automatic application machine (manufactured by Lintec Corporation, product name "RAD-3510") Roller pressure: 0.5MPa Roller height: -400μm Application speed: 5mm / sec Application temperature: 90℃

[0226] The shear modulus G' of the layer (X1) was 1,000 Pa. The shear modulus G' was measured by the following method. For the first curable resin (x1), 10 sheets of the first curable resin (x1) with a thickness of 100 μm were laminated to prepare a layer (X1) of the first curable resin (x1) with a thickness of 1 mm. Next, this first curable resin (x1) was cut into a disk with a diameter of 8 mm to obtain a test piece of the layer (X1) of the first curable resin (x1). Then, the installation location of the test piece in the shear viscosity measurement device: dynamic viscoelasticity measurement device (ARES; manufactured by TA Instruments) was kept warm at 90 ° C in advance, and the test piece was placed on this installation location, and the test piece was fixed and installed at the installation location by pressing a measurement jig against the upper surface of the test piece. Next, a 400% strain was generated in the test piece under conditions of a temperature of 90 ° C and a measurement frequency of 1 Hz, and the shear modulus G' of the test piece was measured.

[0227] The first curable resin (x1) was produced using the first thermosetting resin composition (x1-1-1). The components used in preparing the first thermosetting resin composition (x1-1-1) are shown below. Polymer component Polymer component (A)-1: An acrylic resin (weight average molecular weight 800,000, glass transition temperature -28°C) obtained by copolymerizing butyl acrylate (hereinafter abbreviated as "BA") (55 parts by mass), methyl acrylate (hereinafter abbreviated as "MA") (10 parts by mass), glycidyl methacrylate (hereinafter abbreviated as "GMA") (20 parts by mass), and 2-hydroxyethyl acrylate (hereinafter abbreviated as "HEA") (15 parts by mass). Epoxy resin Epoxy resin (B1)-1: liquid bisphenol F epoxy resin ("YL983U" manufactured by Mitsubishi Chemical Corporation); weight average molecular weight = 340 Epoxy resin (B1)-2: polyfunctional aromatic epoxy resin ("EPPN-502H" manufactured by Nippon Kayaku Co., Ltd.); weight-average molecular weight = 1,000 Epoxy resin (B1)-3: dicyclopentadiene-type epoxy resin (DIC Corporation, "EPICLON HP-7200"); weight-average molecular weight = 600 Heat curing agent Heat curing agent (B2)-1: Novolac type phenolic resin ("BRG-556" manufactured by Showa Denko K.K.) Curing accelerator Curing accelerator (C) - 1:2-phenyl-4,5-dihydroxymethylimidazole ("Curezol 2PHZ-PW" manufactured by Shikoku Chemicals Corporation) ·Filling material Filler (D)-1: Epoxy-modified spherical silica ("Admanano YA050C-MKK" manufactured by Admatechs Co., Ltd.); 0.05 μm (average particle size); 19% by mass (content in the first thermosetting resin composition (x1-1-1))

[0228] 100 parts by mass of polymer component (A)-1, 135 parts by mass of epoxy resin (B1)-1, 90 parts by mass of epoxy resin (B1)-2, 150 parts by mass of epoxy resin (B1)-3, 180 parts by mass of thermosetting agent (B2)-1, 1 part by mass of curing accelerator (C)-1, and 160 parts by mass of filler (D)-1 were dissolved or dispersed in methyl ethyl ketone and stirred at 23°C to prepare a first thermosetting resin composition (x1-1-1) having a solids concentration of 55% by mass.

[0229] The first thermosetting resin composition (x1-1-1) obtained above was applied to the release-treated surface of a release film ("SP-PET381031" manufactured by Lintec Corporation, thickness 38 μm), one side of which had been treated for release by silicone treatment, and dried at 100°C for 2 minutes to produce a first thermosetting resin film (x1-1) having a thickness of 90 μm as the first curable resin (x1). Next, the exposed surface of the first curable resin (x1) was bonded to the exposed surface of the adhesive layer of the backgrinding tape, thereby obtaining a first laminate (α1) in which the backgrinding tape, the first curable resin (x1), and the release film were laminated in this order in the thickness direction. When this first laminate (α1) was attached to a wafer for producing semiconductor chips, the release film was peeled off from the first laminate (α1) to expose the first curable resin (x1).

[0230] 3. Evaluation The semiconductor chip fabrication wafer with the first curable resin (x1) attached was heated at 160°C for 1 hour to harden it into a first curable resin film (r1), and then back-grinding was performed to grind the back surface by 625 μm to make the thickness of the semiconductor chip fabrication wafer 150 μm. After that, back surface observation and cross-sectional polishing observation were performed. Cross-sectional polishing observation was performed using an optical microscope (Keyence Corporation "VHX-1000").

[0231] 4.Results FIG. 13 shows the results of rear surface observation, and FIG. 14 shows the results of cross-sectional polishing observation. Both results confirmed that the first cured resin film (r1) was well embedded in the grooves 13. Furthermore, the cross-sectional polishing observation confirmed that the first cured resin film (r1) also had good coverage on the wafer surface. These results confirmed that the manufacturing method of the present invention makes it possible to obtain semiconductor chips whose bump-forming surfaces and side surfaces are well covered with the first cured resin film (r1). [Explanation of symbols]

[0232] 10. Wafers for semiconductor chip manufacturing 11 wafers 11a Bump forming surface 11b Back side 12 Bump 13 Groove 40 Semiconductor Chips x1 First hardening resin r1 First cured resin film X1 layer Y1 First support sheet α1 First laminate x2 Second hardening resin r2 Second cured resin film X2 layer Y2 Second support sheet α2 Second laminate 51 Substrate 61 Adhesion layer 71 Intermediate Layer

Claims

1. The method includes the following steps (S1) to (S4) in this order: Step (S1): A step of preparing a semiconductor chip manufacturing wafer having a bump-forming surface on which grooves as planned division lines are formed so as not to reach the rear surface of the semiconductor wafer. Step (S2): A step of pressing a first hardening resin (x1) onto the bump-formed surface of the semiconductor chip fabrication wafer to cover the bump-formed surface of the semiconductor chip fabrication wafer with the first hardening resin (x1) and embedding the first hardening resin (x1) in the grooves formed in the semiconductor chip fabrication wafer. Step (S3): A step of curing the first curable resin (x1) to obtain a semiconductor chip fabrication wafer with a first cured resin film (r1) thereon. Step (S4): A step of dividing the semiconductor chip manufacturing wafer with the first cured resin film (r1) along the planned dividing lines to obtain semiconductor chips in which at least the bump-forming surface and side surfaces are covered with the first cured resin film (r1). The method for manufacturing a semiconductor chip further includes the following step (S-BG) after the step (S2) and before the step (S3), after the step (S3) and before the step (S4), or in the step (S4): Step (S-BG): Grinding the back surface of the semiconductor chip fabrication wafer The step (S2) is carried out by pressing a first laminate (α1) having a laminate structure in which a first support sheet (Y1) and a layer (X1) of the first curable resin (x1) are laminated onto the bump formation surface of the semiconductor chip production wafer, with the layer (X1) serving as an attachment surface, and attaching the first laminate (α1). In the step (S-BG), the amount of grinding when grinding the back surface of the semiconductor chip fabrication wafer is an amount that exposes at least the bottoms of the grooves of the semiconductor chip fabrication wafer.

2. The step (S-BG) is included after the step (S2) and before the step (S3), the step (S-BG) is carried out by grinding the back surface of the semiconductor chip production wafer with the first laminate (α1) attached, and then peeling the first support sheet (Y1) from the first laminate (α1); 2. The method for manufacturing a semiconductor chip according to claim 1, wherein the step (S4) is carried out by cutting the portion of the first cured resin film (r1) of the semiconductor chip manufacturing wafer having the first cured resin film (r1) formed in the groove portion along the planned dividing line.

3. The step (S-BG) is included after the step (S3) and before the step (S4), The step (S3) is carried out without peeling the first support sheet (Y1) from the first laminate (α1), the step (S-BG) is carried out by grinding the back surface of the semiconductor chip production wafer with the first laminate (α1) attached, and then peeling the first support sheet (Y1) from the first laminate (α1); 2. The method for manufacturing a semiconductor chip according to claim 1, wherein the step (S4) is carried out by cutting the portion of the first cured resin film (r1) of the semiconductor chip manufacturing wafer having the first cured resin film (r1) formed in the groove portion along the planned dividing line.

4. The step (S-BG) is included after the step (S3) and before the step (S4), After the step (S2) and before the step (S3), the first support sheet (Y1) is peeled off from the first laminate (α1), The step (S-BG) is carried out by attaching a back-grinding sheet (b-BG) to the surface of the first cured resin film (r1) of the semiconductor chip production wafer having the first cured resin film (r1), grinding the back surface of the semiconductor chip production wafer with the back-grinding sheet (b-BG) attached, and then peeling off the back-grinding sheet (b-BG) from the semiconductor chip production wafer having the first cured resin film (r1); 2. The method for manufacturing a semiconductor chip according to claim 1, wherein the step (S4) is carried out by cutting the portion of the first cured resin film (r1) of the semiconductor chip manufacturing wafer having the first cured resin film (r1) formed in the groove portion along the planned dividing line.

5. The step (S-BG) is included in the step (S4), After the step (S2) and before the step (S3), the first support sheet (Y1) is peeled off from the first laminate (α1), 2. The method for manufacturing a semiconductor chip according to claim 1, wherein the step (S4) is performed by making an incision along the planned dividing line in the portion of the first cured resin film (r1) of the semiconductor chip manufacturing wafer formed in the groove portion of the first cured resin film (r1) of the semiconductor chip manufacturing wafer with the first cured resin film (r1) or by forming a modified region along the planned dividing line, and then, in the step (S-BG), attaching a back-grinding sheet (b-BG) to the surface of the first cured resin film (r1) of the semiconductor chip manufacturing wafer with the first cured resin film (r1) attached, and grinding the back surface of the semiconductor chip manufacturing wafer with the back-grinding sheet (b-BG) attached.

6. The method for producing a semiconductor chip according to any one of claims 1 to 5, further comprising the following step (T): Step (T): forming a second cured resin film (r2) on the back surface of the semiconductor chip fabrication wafer.

7. The method for producing a semiconductor chip according to any one of claims 1 to 6, further comprising the following step (U): Step (U): A step of removing the first cured resin film (r1) covering the top of the bump or the first cured resin film (r1) attached to a part of the top of the bump to expose the top of the bump.

8. 8. The method for manufacturing a semiconductor chip according to claim 7, wherein the step (U) is performed by a plasma etching process.

9. A strain dispersion measurement was performed to measure the shear modulus G' of the test piece of the layer (X1) by generating a strain of 400% under the conditions of a temperature of 90°C and a frequency of 1 Hz. The shear modulus G' was found to be in the range of 5.0 × 10 Pa to 1.0 × 10 ６ The method for manufacturing a semiconductor chip according to any one of claims 1 to 8, wherein Pa is

10. The method for manufacturing a semiconductor chip according to any one of claims 1 to 9, wherein the thickness of the layer (X1) is 10 µm or more and 200 µm or less.

11. The method for manufacturing a semiconductor chip according to any one of claims 1 to 10, wherein the groove has a width of 10 µm to 2000 µm.

12. The method for manufacturing a semiconductor chip according to any one of claims 1 to 11, wherein the depth of the groove is 30 μm to 700 μm.

13. The method for manufacturing a semiconductor chip according to any one of claims 1 to 12, wherein the first cured resin film (r1) is transparent.

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