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 such that the circuit surface of the semiconductor chip faces the substrate, thereby mounting the semiconductor chip on the substrate. Incidentally, the semiconductor chips are usually obtained by dicing a semiconductor wafer having bumps on its circuit surface.

[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, with the thermosetting resin layer as the bonding surface, to a bump-forming surface of a semiconductor wafer having bumps, and then the thermosetting resin layer is heated and cured to form a protective film. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2015-092594 A [Patent Document 2] JP 2012-169484 A Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, as IC-embedded products such as electronic devices have become smaller and thinner, there has been a growing demand for thinner semiconductor chips. However, as the semiconductor chip becomes thinner, its strength decreases. This causes a problem that the semiconductor chip becomes more susceptible to damage, for example, when the semiconductor chip is transported or when the semiconductor chip is packaged in a post-process. Therefore, it is conceivable to form a protective film on the bump-forming surface of the semiconductor wafer to protect the bump neck and to 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. In addition, 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 a protective film is suppressed. [Means for solving the problem]

[0007] The inventors came up with the idea that by providing a protective film for protecting the bump neck on the side surface of the semiconductor chip as well, the strength of the semiconductor chip can be improved and peeling of the protective film can be suppressed, resulting in an extremely rational configuration. As a result of extensive research based on this idea, the inventors 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 a groove portion is formed as a division line on the bump-forming surface 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 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 wafer for producing semiconductor chips having a first cured resin film (r1) thereon. Step (S4): A step of dividing the semiconductor chip manufacturing wafer having the first cured resin film (r1) along the intended division lines to obtain semiconductor chips having at least the bump formation surface and side surfaces 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): A step of grinding the back surface of the semiconductor chip fabrication wafer. [2] The method for producing 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 production wafer, using the layer (X1) 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 performed 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 intended 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 performed 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 intended 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-grind 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-grind sheet (b-BG) attached, and then peeling off the back-grind 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 performed 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 intended division line. [6] The process (S-BG) is included in the process (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 division line in a portion of the first cured resin film (r1) of the semiconductor chip manufacturing wafer having the first cured resin film (r1) that is formed in the groove portion, or by forming a modified region along the planned division line, and then, as the step (S-BG), attaching a backgrind sheet (b-BG) to the surface of the first cured resin film (r1) of the semiconductor chip manufacturing wafer having the first cured resin film (r1), and grinding the back surface of the semiconductor chip manufacturing wafer with the backgrind sheet (b-BG) attached. [7] A 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] A method for producing a semiconductor chip according to any one of the above [1] to [7], further comprising the following step (U): Step (U): 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 was 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' was found to be 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 layer (X1) has a thickness of 10 μm or more and 200 μm or less.

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

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

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

[12] , wherein the groove has a depth of 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. Effect of the Invention

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

[0010] [Figure 1] 1 is a schematic diagram showing steps of a method for manufacturing a semiconductor chip according to the present invention. [Diagram 2] FIG. 2 is a top view showing an example of a wafer for fabricating semiconductor chips prepared in step (S1). [Diagram 3] 2 is a schematic cross-sectional view showing an example of a wafer for fabricating semiconductor chips prepared in step (S1). FIG. [Figure 4] FIG. 2 is a diagram showing an outline of step (S2). [Diagram 5] 1 is a diagram showing an outline of a manufacturing method according to a first embodiment. [Figure 6] 5A to 5C are diagrams illustrating an outline of a manufacturing method according to a second embodiment. [Figure 7] 13A to 13C are diagrams illustrating an outline of a manufacturing method according to a third embodiment. [Figure 8] 13A to 13C 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 configuration 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. 4 is a schematic cross-sectional view showing another example of the specific configuration of the first laminate (α1). [Figure 12] FIG. 11 is a schematic cross-sectional view showing still another example of the specific configuration of the first laminate (α1). [Figure 13] 1 is a drawing-substitute photograph 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 PREFERRED EMBODIMENTS

[0011] In this specification, the term "active ingredient" refers to the components contained in the target composition excluding diluting 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 polystyrene equivalent values ​​measured by gel permeation chromatography (GPC). In this specification, the lower limit and upper limit described in stages for the preferred numerical range (e.g., the range of the content, etc.) 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 the semiconductor chip of 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 manufacturing semiconductor chips, 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 manufacturing semiconductor chips.

[0013] In detail, 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 a groove portion is formed as a division line on the bump-forming surface 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 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 wafer for producing semiconductor chips having a first cured resin film (r1) thereon. Step (S4): A step of dividing the semiconductor chip manufacturing wafer having the first cured resin film (r1) along the intended division lines to obtain semiconductor chips having at least the bump formation surface and side surfaces 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): A step of 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 susceptible to peeling of the first cured resin film (r1) acting as a protective film. In this case, "covered" means that the first cured resin film (r1) is formed on at least the bump-forming surface and the side surface of one semiconductor chip, following the shape of the semiconductor chip. In other words, the present invention is clearly different from the sealing technology that confines multiple semiconductor chips in resin.

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

[0016] [Process (S1)] FIG. 2 shows a top view of an example of the semiconductor wafer prepared in step (S1), and FIG. 3 shows a schematic cross-sectional view thereof. In step (S1), a wafer 10 for manufacturing semiconductor chips is prepared, in which a groove portion 13 is formed as a planned division line on the bump formation surface 11a of the semiconductor wafer 11 having bumps 12 thereon so as not to reach the back surface 11b. Note that bumps are omitted in Fig. 2. Also, in the drawings used in the following description, in order to make the features of the present invention easier to understand, the main parts may be shown enlarged for convenience, and the dimensional ratios of each component may not necessarily be the same as the actual ones.

[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 bump 12 is spherical, but the bump 12 may be a spheroid. The spheroid may be, for example, a spheroid stretched in a direction perpendicular to the bump-forming surface 11a of the wafer 11, or a spheroid stretched in a direction horizontal to the bump-forming surface 11a of the wafer 11. The bump 12 may also be pillar-shaped.

[0018] The height of the bump 12 is not particularly limited and may be appropriately changed 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" refers to the height of a single bump at its highest point from the bump-forming surface 11a.

[0019] The number of bumps 12 is not particularly limited, 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 of the material 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 a rectangle. In the case of a polygonal wafer, the size of wafer 11 is preferably such that the length of the longest side 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 from the viewpoint of easily suppressing warpage due to shrinkage when the first curable resin (x1) is cured and from the viewpoint of suppressing the amount of grinding of the back surface 11b of the wafer 11 in a later step and shortening the time required for back surface grinding, the thickness is preferably 100 μm to 1,000 μm, more preferably 200 μm to 900 μm, and even more preferably 300 μm to 800 μm.

[0023] A bump formation surface 11a of a semiconductor chip fabrication wafer 10 prepared in step (S1) has a plurality of grooves 13 formed in a lattice pattern as planned division lines when the semiconductor chip fabrication wafer 10 is diced. The plurality of grooves 13 are cut 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 part of the grooves 13 does not reach the back surface 11b of the wafer 11. The plurality of grooves 13 can be formed by dicing using a conventionally known wafer dicing device equipped with a dicing blade. The plurality of grooves 13 can also be formed by dicing using a laser or the like instead of a blade. The grooves 13 may be formed in any shape so long as 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 lattice 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 according to 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 further preferably 100 μm to 500 μm.

[0026] The semiconductor chip fabrication wafer 10 prepared in the step (S1) is subjected to a 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 and attached to the bump formation surface 11a of the semiconductor chip fabrication wafer 10. Here, from the viewpoint of the handleability of the first hardening resin (x1), the first hardening resin (x1) is preferably used by being laminated on a first support sheet (Y1). Therefore, in step (S2), it is preferable to press and attach a first laminate (α1) having a laminated 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 production wafer 10, using the layer (X1) as an attachment surface. In step (S2), as shown in FIG. 4, the bump formation surface 11a of the semiconductor chip production wafer 10 is covered with a first curable resin (x1), and the first curable resin (x1) is embedded in the grooves 13 formed in the semiconductor chip production wafer 10.

[0028] By embedding the first curable resin (x1) in the grooves 13 formed in the semiconductor chip fabrication wafer 10, the portions that will become the side surfaces of the semiconductor chips when the semiconductor chip fabrication wafer 10 is diced in step (S4) can be covered with the first curable resin (x1). That is, a coating that is a precursor of the first cured resin film (r1) that covers the side surfaces of the semiconductor chips and is necessary to enhance the strength of the semiconductor chips and to suppress peeling of the first cured resin film (r1) as a protective film can be formed in step (S2).

[0029] The pressing force 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 improving the embedding property of the first curable resin (x1) in the grooves 13. The pressing force when attaching the first laminate (α1) to the semiconductor chip fabrication wafer 10 may be appropriately changed from the beginning to the end of attachment. For example, from the viewpoint of improving the embedding property of the first curable resin (x1) in the groove portion 13, it is preferable to make the pressing force low in the beginning of 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) is temporarily increased by heating, and the first curable resin (x1) is hardened by continuing to heat the first curable resin (x1). Thus, by heating the first curable resin (x1) within a range in which the fluidity of the first curable resin (x1) is improved, the first curable resin (x1) can easily spread 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 further 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 carry out the attachment in a reduced pressure environment. This creates a negative pressure in the grooves 13, which makes 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 even more preferably more than 30 μm, from the viewpoint of improving the embedding property of the first curable resin (x1) into the groove portion 13. The thickness is preferably 200 μm or less, more preferably 150 μm or less, even more preferably 130 μm or less, even 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). For example, the thickness of the layer (X1) consisting of multiple layers means the total thickness of all layers constituting the layer (X1).

[0033] Further, 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 preferably configured to have a shear modulus G' of 5.0×10 Pa to 1.0×10 Pa when a strain dispersion measurement is performed to measure the shear modulus G' of a test piece of the layer (X1) by generating a 400% strain in the test piece of the layer (X1) under conditions of a temperature of 90° C. and a frequency of 1 Hz. 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), etc.

[0034] Here, the first support sheet (Y1) of the first laminate (α1) preferably supports the first curable resin (x1) and 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)] Through the steps up to the step (S2) above, a laminate is formed by attaching and laminating the first laminate (α1) 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 carrying out the step (S-BG). Hereinafter, for the first to fourth embodiments, steps (S3) and (S4) will be described together with an explanation of the timing for performing step (S-BG).

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

[0037] (First embodiment: step (S-BG)) In the first embodiment, first, the 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 the same 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 wafer 10 for manufacturing semiconductor chips should be at least an amount that exposes the bottoms of the groove portions 13 of the wafer 10 for manufacturing semiconductor chips, but further grinding may be performed so that the first curable resin (x1) embedded in the groove portions 13 is also ground together with the wafer 10 for manufacturing semiconductor chips. In the first embodiment, since the first support sheet (Y1) is peeled off before carrying out the step (S3), even if the first curable resin (x1) is a thermosetting resin and a heat treatment is carried out for curing in the step (S3), the first support sheet (Y1) is not required to have heat resistance, and therefore the degree of freedom in designing the first support sheet (Y1) is improved.

[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 neck is well protected. In addition, in step (S4) shown in FIG. 5 (1-d), the semiconductor chip fabrication wafer 10 with the first cured resin film (r1) is diced into individual pieces to obtain semiconductor chips whose side surfaces are also covered with the first cured resin film (r1), and thus semiconductor chips with excellent strength are obtained. Moreover, 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 of such beams include ultraviolet rays and electron beams, with ultraviolet rays being preferred. As for the conditions for thermal curing, 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 irradiation with energy rays are appropriately set depending on the type of energy rays used. For example, when ultraviolet rays are used, the illuminance is preferably 170 mW / cm 2 ~250mw / cm 2 and the light dose is preferably 300 mJ / cm 2 ~3,000mJ / cm 2 It is. Here, in the process of curing the first curable resin (x1) to form the first cured resin film (r1), from the viewpoint of removing air bubbles and the like that may enter when the groove portion 13 is filled with the first curable resin (x1) in the step (S2), the first curable resin (x1) is preferably a thermosetting resin. That is, when the first curable resin (x1) is a thermosetting resin, the fluidity of the first curable resin (x1) is temporarily increased by heating, and the first curable resin (x1) is cured by continuing the heating. By utilizing this phenomenon, when the fluidity of the first curable resin (x1) is increased, air bubbles and the like that may enter 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 portion 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 portion is cut along the planned division line. The cutting can be appropriately carried out 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 surface are covered with the first cured resin film (r1). In addition, because the bump-forming surface 11a and the side surface are continuously covered with the first cured resin film (r1), the joint surface (interface) between the bump-forming surface 11a and the first cured resin film (r1) is not exposed on the side surface of the semiconductor chip 40. Of the joint surface (interface) between the bump-forming surface 11a and the first cured resin film (r1), the exposed portion exposed on the side surface of the semiconductor chip 40 is likely to become the starting point of film peeling. Since the semiconductor chip 40 of the present invention does not have the 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 in which peeling of the first cured resin film (r1) as a protective film is suppressed can be obtained.

[0041] In step (S4), when the portion of the first cured resin film (r1) of the semiconductor chip fabrication wafer 10 with the first cured resin film (r1) formed in the groove portion is cut along the planned division line, it is preferable that the first cured resin film (r1) is transparent. Since the first cured resin film (r1) is transparent, the semiconductor wafer 11 can be seen through, ensuring visibility of the planned division line. Therefore, it becomes easier to cut along the planned division line.

[0042] Second Embodiment In the second embodiment, as shown in FIG. 1, a step (S-BG) is performed after the step (S3) and before the 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). 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 neck is well protected. Furthermore, by dividing the semiconductor chip fabrication wafer 10 with the first cured resin film (r1) into individual pieces in step (S4), it is possible to obtain semiconductor chips whose side surfaces are also covered with the first cured resin film (r1), and thus semiconductor chips with excellent strength are obtained. 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 heat curing process without peeling off the first support sheet (Y1), it is possible to suppress the flow of the first hardening resin (x1) on the surface that occurs temporarily when the first hardening resin (x1) is hardened by the first support sheet (Y1) during heat curing, and it is possible to improve the flatness of the first hardening resin film (r1) on the bump formation surface. In addition, by hardening the first hardening resin (x1) before grinding the back surface 11b of the semiconductor chip fabrication wafer 10, warping of the semiconductor chip fabrication wafer 10 is suppressed.

[0044] (Second embodiment: step (S-BG)) After the step (S3), the step (S-BG) is performed. 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 wafer 10 for manufacturing semiconductor chips should be an amount that exposes at least the bottom of the groove portion 13 of the wafer 10 for manufacturing semiconductor chips, but further grinding may be performed so that the first cured resin film (r1) embedded in the groove portion 13 is also ground together with the wafer 10 for manufacturing semiconductor chips. 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 performing the step (S-BG), the step (S4) is performed in the same manner as in the first embodiment. Specifically, as shown in FIG. 6 (2-d), the portion 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 portion is cut along the planned division line. The cutting can be appropriately carried out 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 surface are covered with the first cured resin film (r1). Also, for the reasons described above, the semiconductor chip 40 can be obtained in which peeling of the first cured resin film (r1) as a protective film is suppressed.

[0046] <Third embodiment> The third embodiment is common to the second embodiment in that a step (S-BG) is performed after the step (S3) and before the step (S4), as shown in Fig. 1. However, the third embodiment differs from the second embodiment in that a back grind 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, but 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), even if the first curable resin (x1) is a thermosetting resin and a heat treatment is carried out for curing in the step (S3), the first support sheet (Y1) is not required to have heat resistance, which improves the freedom of design of 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, warping 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 (3-c) of FIG. 7, a backgrind sheet (b-BG) is attached to the surface of the first cured resin film (r1) of the semiconductor chip fabrication wafer 10 with the first cured resin film (r1). Next, as shown in (3-d) of FIG. 7, the back surface 11b of the semiconductor chip fabrication wafer 10 is ground with the backgrind sheet (b-BG) attached, and then, as shown in (3-e) of FIG. 7, the backgrind sheet (b-BG) is peeled off from the semiconductor chip fabrication wafer 10 with the first cured resin film (r1). Since the backgrind 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 backgrind sheet (b-BG) is not required to have heat resistance. Therefore, the degree of freedom in designing the backgrind sheet (b-BG) is improved. The amount of grinding when grinding the back surface 11b of the wafer 10 for manufacturing semiconductor chips should be an amount that exposes at least the bottom of the groove portion 13 of the wafer 10 for manufacturing semiconductor chips, but further grinding may be performed so that the first cured resin film (r1) embedded in the groove portion 13 is also ground together with the wafer 10 for manufacturing semiconductor chips.

[0049] (Third embodiment: step (S4)) After performing the step (S-BG), the step (S4) is performed in the same manner as in the first and second embodiments. Specifically, as shown in (3-f) of Fig. 7, the portion 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 portion is cut along the planned division line. The cutting can be appropriately carried out 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 surface are covered with the first cured resin film (r1). Also, for the reasons described above, the semiconductor chip 40 can be obtained in which peeling of the first cured resin film (r1) as a protective film is suppressed.

[0050] <Fourth embodiment> In the fourth embodiment, as shown in FIG. 1, the step (S-BG) is carried out 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, but 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), even if the first curable resin (x1) is a thermosetting resin and a heat treatment is carried out for curing in the step (S3), the first support sheet (Y1) is not required to have heat resistance, which improves the freedom of design of 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, warping of the semiconductor chip fabrication wafer 10 is suppressed.

[0052] (Fourth embodiment: step (S4) including step (S-BG)) After carrying out step (S3), as shown in FIG. 8 (4-c), a cut is made along the intended division line in the portion 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 portion 13. From the viewpoint of facilitating singulation, the depth of the cut is preferably set to a depth that reaches the deepest portion of the groove portion 13. As a result, in step (S-BG) described later, the semiconductor chip fabrication wafer 10 having the first cured resin film (r1) is singulated along the cut. Alternatively, although not shown, a modified region may be formed along the intended division line in a portion of the first cured resin film (r1) of the semiconductor chip fabrication wafer 10 with the first cured resin film (r1) that is formed in the groove portion 13. The modified region can be formed by laser or plasma treatment, etc. As a result, in a step (S-BG) described later, cracks are generated starting from the modified region, and the semiconductor chip fabrication wafer 10 with the first cured resin film (r1) is divided into individual pieces along the modified region. 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 with 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 with 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 wafer 10 for manufacturing semiconductor chips should be an amount that exposes at least the bottom of the groove portion 13 of the wafer 10 for manufacturing semiconductor chips, but further grinding may be performed so that the first cured resin film (r1) embedded in the groove portion 13 is also ground together with the wafer 10 for manufacturing semiconductor chips. The semiconductor chip 40 has excellent strength since the bump-forming surface 11a and the side surfaces are covered with the first cured resin film (r1). In addition, since the backgrind sheet (b-BG) is not used in the step (S3), even if the first curable resin (x1) is a thermosetting resin and a heat treatment is performed for curing in the step (S3), the backgrind sheet (b-BG) is not required to have heat resistance. Therefore, the degree of freedom in designing the backgrind sheet (b-BG) is improved.

[0053] Here, in the first to fourth embodiments, an embodiment in which a first support sheet (Y1) or a back-grind sheet (b-BG) is used in step (S-BG) has been described. 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-grind sheet (b-BG). Specifically, a flowable resin (z1) is used to cover the surface of the first cured resin film (r1) and also to cover the bumps exposed from the first cured resin film (r1), and then the resin (z1) is cured to form a resin layer (Z1) for backgrinding, which can be used as a substitute for a backgrind sheet in the grinding process. When covering the surface of the first cured resin film (r1) and the bumps exposed from the first cured resin film (r1) with resin (z1), the resin layer (Z1) for back grinding, which is no longer needed after the step (S-BG), can be easily peeled off by covering the surface of the first cured resin film (r1) and the bumps exposed from the first cured resin film (r1) with a flexible resin film (z2) capable of conforming to the unevenness of the bumps.

[0054] [Process (T)] In one aspect of the method for producing a semiconductor chip of the present invention, it is preferable that the method further comprises 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 carry out the above step (T).

[0056] More specifically, the above step (T) preferably includes the following step (T1) to step (T2) in this order. Step (T1): A step of attaching a second curable resin (x2) to the back surface 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, using the layer (X2) 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 may be 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) supports the second curable resin (x2) and also functions as a dicing sheet. In the manufacturing methods of the first to third embodiments, since the second laminate (α2) is attached to the back surface 11b of the semiconductor wafer 10 with the first cured resin film (r1) in step (S4), the second support sheet (Y2) functions as a dicing sheet when dicing into individual pieces, making it easier to perform dicing.

[0058] Here, in the case where step (S3) is carried out after step (S-BG) as in the manufacturing method according to the first embodiment, the above step (T1) may be carried out before carrying out step (S3), and then step (S3) and step (T2) may be carried out simultaneously. That is, the first curable resin (x1) and the second curable resin (x2) may be cured at the same time. This can reduce the number of times of curing treatment.

[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) before or after step (S4) to form a second cured resin film (r2) In step (S4), when cutting the portion of the first cured resin film (r1) formed in the groove portion of the semiconductor chip production wafer with the first cured resin film (r1) along the planned division 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 keeping the backgrind sheet (b-BG) 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): A 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): 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. The exposure process for exposing the tops of the bumps may be, for example, an etching process such as a wet etching process or a dry etching process. Here, the dry etching process may be, for example, a plasma etching process. When the tops of the bumps are not exposed on the surface of the protective film, the exposing process may be performed for the purpose of retracting the protective film until the tops of the bumps are exposed.

[0061] The timing of performing 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 the step (U) is performed 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 grind 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)] FIG. 9 shows an example of the structure of the first laminate (α1) used in the production method according to one embodiment of the present invention. The first laminate (α1) used in the manufacturing method of one embodiment of the present invention has a layer (X1) of a first hardening 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 hardening resin (x1) on one surface of the first support sheet (Y1), the layer (X1) of the first hardening resin (x1) is stably supported and protected when the layer (X1) of the first hardening resin (x1) is transported as a product package or when the layer (X1) of the first hardening resin (x1) is conveyed in a process.

[0064] Specific examples of the structure 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. In addition, the first laminate (α1) may be, like the first laminate (α1b) shown in FIG. 11, a first support sheet (Y1) which is an adhesive sheet formed by laminating a base material 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 a first support sheet (Y1) in which a substrate 51, an intermediate layer 71, and an adhesive layer 61 are laminated in this order, as in the first laminate (α1c) shown in FIG. 12, and the adhesive layer 61 of the adhesive sheet and the layer (X1) of the first curable resin (x1) may be bonded together. The adhesive sheet in which the substrate 51, the intermediate layer 71, and the adhesive layer 61 are laminated in this order can be suitably used as a backgrind tape. That is, since the first laminate (α1c) shown in FIG. 12 has a backgrind tape as the first support sheet (Y1), it can be suitably used when grinding the back surface 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 used to cover the bump formation surface of the semiconductor chip fabrication wafer and to fill the grooves formed in the semiconductor chip fabrication wafer, and forms a first cured resin film (r1) by curing through heating or energy ray irradiation. That is, the first curable resin (x1) may be a thermosetting resin film that is cured by heating (hereinafter also referred to as "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 "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 types of the polymer component (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 (meth)acryloyl groups), polyvinyl acetal, polyester, urethane resins (resins having urethane bonds), acrylic urethane resins, silicone resins (resins having siloxane bonds), rubber resins (resins having a rubber structure), phenoxy resins, and thermosetting polyimides. Of these, acrylic resins and polyvinyl acetals are preferred.

[0072] The acrylic resin may be a known acrylic polymer. From the viewpoint of making it easier to exert the effects of the present invention, the weight average molecular weight (Mw) of the acrylic resin is preferably from 10,000 to 2,000,000, more preferably from 300,000 to 1,500,000, and even more preferably from 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. Also, 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 adapted to the uneven surface of the adherend, and for example, the occurrence of voids between the adherend and the first thermosetting resin film (x1-1) is easily suppressed. Therefore, not only the coverage of the bump-forming surface 11a of the semiconductor wafer 11 but also the embedding property in the groove portion 13 is easily improved.

[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, and the peelability of the first support sheet (Y1) is improved. 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 suppressed.

[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)acrylic acid alkyl esters in which the alkyl group constituting the alkyl ester has a chain structure having 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 of such esters include (meth)acrylic acid esters containing a substituted amino group, such as N-methylaminoethyl (meth)acrylate. In this specification, the term "substituted amino group" refers to an amino group in which one or two hydrogen atoms have been replaced 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, it is preferable that the alkyl group constituting the alkyl ester is a copolymer combining an alkyl (meth)acrylate having a chain structure of 1 to 18 carbon atoms, a glycidyl group-containing (meth)acrylate, and a hydroxyl group-containing (meth)acrylate, it is more preferable that the alkyl group constituting the alkyl ester is a copolymer combining an alkyl (meth)acrylate having a chain structure of 1 to 4 carbon atoms, a glycidyl group-containing (meth)acrylate, and a hydroxyl group-containing (meth)acrylate, it is even more preferable that the alkyl group constituting the alkyl ester is a copolymer combining butyl acrylate, methyl acrylate, glycidyl acrylate, and 2-hydroxyethyl acrylate.

[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 monomer constituting the acrylic resin is two or more types, 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 later, 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 by using the first thermosetting resin film (x1-1) tends to be improved.

[0079] The polyvinyl acetal in the polymer component (A) may be any of the known polyvinyl acetals. Among them, 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 lower limit, the shape stability (stability over time during storage) of the first thermosetting resin film (x1-1) is easily improved. When the weight-average molecular weight of the polyvinyl acetal is equal to or less than the above upper limit, the first thermosetting resin film (x1-1) is easily adapted to the uneven surface of the adherend, and for example, the occurrence of voids or the like between the adherend and the first thermosetting resin film (x1-1) is easily suppressed. Therefore, not only the coverage of the bump-forming surface 11a of the semiconductor wafer 11, but also the embedding property in the groove portion 13 is 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 higher than the lower limit, the adhesive strength between the first cured resin film (r1) and the first support sheet (Y1) is suppressed, and the peelability of the first support sheet (Y1) is improved. When the Tg of the polyvinyl acetal 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 suppressed.

[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, as the polymer component (A), a thermoplastic resin other than an acrylic resin and a polyvinyl acetal (hereinafter, may be simply abbreviated as a "thermoplastic resin") may be used alone without using both an acrylic resin and a polyvinyl acetal, or may be used in combination with one or both of an acrylic resin and a polyvinyl acetal. By using a thermoplastic resin, the peelability of the first cured resin film (r1) from the first support sheet (Y1) is improved, and the first thermosetting resin film (x1-1) is easily adapted to the uneven surface of the adherend, and the occurrence of voids between the adherend and the first thermosetting resin film (x1-1) may be further suppressed. Therefore, not only the coverage of the bump formation surface 11a of the semiconductor wafer 11 but also the embedding property into the groove portion 13 is easily improved.

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

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

[0087] Examples of the thermoplastic resin 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 from 5 to 85 mass %, and more preferably from 5 to 80 mass %, based on the total amount of the active ingredients of 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 a component that corresponds 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 alone or in combination of two or more. When the thermosetting component (B) is used in two or more types, 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, silicone resins, etc. Among these, epoxy-based thermosetting resins are preferred.

[0093] The epoxy thermosetting resin comprises 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 kinds of epoxy thermosetting resins are used, the combination and ratio thereof can be selected arbitrarily.

[0094] Epoxy resin (B1) The epoxy resin (B1) may be any known one, such as a polyfunctional epoxy resin, a biphenyl compound, bisphenol A diglycidyl ether and its hydrogenated product, orthocresol novolac epoxy resin, a dicyclopentadiene type epoxy resin, a biphenyl type epoxy resin, a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a phenylene skeleton type epoxy resin, and a di- or higher functional epoxy compound. Among these, from the viewpoint of making it easier to exert the effects of the present invention, it is preferable to use a polyfunctional epoxy resin, a dicyclopentadiene type epoxy resin, and a bisphenol F type epoxy resin. Furthermore, among the polyfunctional epoxy resins, a polyfunctional aromatic type epoxy resin is preferable.

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

[0096] As the epoxy resin having an unsaturated hydrocarbon group, for example, a compound obtained by converting a part of the epoxy group of a multifunctional epoxy resin into a group having an unsaturated hydrocarbon group can be mentioned. Such a compound can be obtained, for example, by adding (meth)acrylic acid or its derivative to an epoxy group. In addition, as the epoxy resin having an unsaturated hydrocarbon group, for example, a compound in which a group having an unsaturated hydrocarbon group is directly bonded to an aromatic ring or the like constituting the epoxy resin can be mentioned. 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 from 100 to 1,000 g / eq, and more preferably from 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 capable of reacting with an epoxy group in one molecule. 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, and the like. The phenolic hydroxyl group, the amino group, or an anhydride group of an acid group is preferable, and the phenolic hydroxyl group or the amino group is more preferable.

[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 aralkylphenolic 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 exert the effects of the present invention, a phenol-based curing agent having a phenolic hydroxyl group is preferred, and a novolac-type phenolic resin is more preferred.

[0101] The heat curing agent (B2) may have an unsaturated hydrocarbon group. Examples of the heat curing agent (B2) having an unsaturated hydrocarbon group include a compound in which a part of the hydroxyl groups of a phenolic resin is replaced 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, etc. The unsaturated hydrocarbon group in the heat curing 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 heat curing agent (B2), it is preferable that the heat curing agent (B2) has a high softening point or glass transition temperature, from the viewpoint of easily 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 components, such as biphenol and dicyandiamide, is not particularly limited, but is preferably 60 to 500, for example.

[0104] The heat curing agent (B2) may be used alone 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, 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 more than the above lower limit, the curing of the first thermosetting resin film (x1-1) proceeds more easily. In addition, 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 1000 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 polymer component (A). When the content of the thermosetting component (B) is within such a range, the adhesive strength between the first cured resin film (r1) and the first support sheet (Y1) is suppressed, and the peelability of the first support sheet (Y1) is improved.

[0107] (Cure 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 speed 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, from the viewpoint of making it easier to exert the effects of the present invention, imidazoles are preferred, and 2-phenyl-4,5-dihydroxymethylimidazole is more preferred.

[0108] The curing accelerator (C) may be used alone 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] In the first thermosetting resin composition (x1-1-1), when the curing accelerator (C) is used, the content of the curing accelerator (C) is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the content of the thermosetting component (B). When the content of the curing accelerator (C) is equal to or greater than the above lower limit, the effect of using the curing accelerator (C) is more pronounced. In addition, when the content of the curing accelerator (C) is equal to or less than the above upper limit, for example, the effect of suppressing the highly polar curing accelerator (C) from migrating to the adhesive interface with the adherend in the first thermosetting resin film (x1-1) and segregating under high temperature and high humidity conditions is enhanced, and the reliability of the package obtained using the first thermosetting resin film (x1-1) is further improved.

[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). By including the filler (D), it becomes easier to adjust the thermal expansion coefficient of the first cured resin film (r1) obtained by curing the first thermosetting resin film (x1-1) to an appropriate range, and the reliability of the package obtained by using the first thermosetting resin film (x1-1) is further improved. Furthermore, by including the filler (D) in the first thermosetting resin film (x1-1), it is also possible to reduce the moisture absorption rate of the first cured resin film (r1) and improve the heat dissipation property.

[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 sphering 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 making it easier to exert the effects of the present invention, it is preferable that the inorganic filler is 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, their combination and ratio 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 such a 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 further preferably 10 nm to 300 nm. The average particle diameter is determined by measuring the outer diameter of one particle at several points and averaging the measured values.

[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 compound or an organic compound, the adhesiveness and adhesion of the first thermosetting resin film (x1-1) and the first cured resin film (r1) to the adherend can be improved. Therefore, peeling of the first cured resin film (r1) as a protective film can be more easily suppressed. In addition, 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 bis(3-(triethoxysilylpropyl)tetrasulfane, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, and imidazole silane.

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

[0118] In the first thermosetting resin composition (x1-1-1), when the coupling agent (E) is used, 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, relative to 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 equal to or more than the above lower limit, the effects of using the coupling agent (E), such as improvement in dispersibility of the filler (D) in the resin and improvement in adhesion of the first thermosetting resin film (x1-1) to the adherend, are more significantly obtained. In addition, when the content of the coupling agent (E) is equal to or less than the above upper limit, the generation of outgassing is more suppressed.

[0119] (Crosslinking agent (F)) When the polymer component (A) used is one having 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, such as the above-mentioned acrylic resin, 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 cause crosslinking. By crosslinking with 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 the organic polyisocyanate compound include aromatic polyisocyanate compounds, aliphatic polyisocyanate compounds, and alicyclic polyisocyanate compounds (hereinafter, these compounds may be collectively referred to as "aromatic polyisocyanate compounds, etc."); trimers, isocyanurates, and adducts of the aromatic polyisocyanate compounds, etc.; and terminal isocyanate 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 a 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; a compound in which one or more of tolylene diisocyanate, hexamethylene diisocyanate, and xylylene diisocyanate are added to all or a portion 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 alone 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] In the first thermosetting resin composition (x1-1-1), when the crosslinking agent (F) is used, 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, relative to 100 parts by mass of the polymer component (A). When the content of the crosslinking agent (F) is equal to or more than the lower limit, the effect of using the crosslinking agent (F) is more remarkable. In addition, 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). Since the first thermosetting resin film (x1-1) contains the energy ray curable resin (G), 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 a compound having at least one polymerizable double bond in the molecule, and an acrylate-based compound having a (meth)acryloyl group is preferable.

[0129] Examples of the acrylate-based compound include chain-type 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 polyalkylene glycol (meth)acrylate include aliphatic skeleton-containing (meth)acrylates; dicyclopentanyl di(meth)acrylate and other cyclic aliphatic skeleton-containing (meth)acrylates; polyethylene glycol di(meth)acrylate and other polyalkylene glycol (meth)acrylates; 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 in the polymerization may be used alone or in combination of two or more. When two or more energy ray curable compounds are used in the 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 alone or in combination of two or more. When the photopolymerization initiator (H) is used in combination of two or more kinds, the combination and ratio thereof can be arbitrarily selected.

[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 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 one and may be arbitrarily selected according to 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, gettering agents, and the like.

[0138] The general-purpose additive (I) may be used alone or in combination of two or more. When the general-purpose additive (I) is used in combination of two or more kinds, 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), within a range that does not impair the effects of the present invention. 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 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 it enables 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 respective components constituting the first thermosetting resin composition. The order of addition of each component when blending is not particularly limited, and two or more components may be added at the same time. When a solvent is used, the solvent may be used by mixing with any other blending components other than the solvent to dilute the blending components in advance, or the solvent may be used by mixing with any other blending components without diluting the other components in advance. 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, a method of mixing by adding ultrasound, etc. The temperature and time during addition and mixing of 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 preferably has adhesive properties, and more preferably is 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)) An example of the polymer (a1) having an energy ray-curable group and a weight average molecular weight of 80,000 to 2,000,000 includes 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, carboxy 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 is a group other than a carboxy group. Among these, it is preferable that the functional group is 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, and may be a copolymer of a monomer other than the acrylic monomer (non-acrylic monomer) in addition to these monomers. 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 carboxyl 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 the carboxy group-containing monomer include ethylenically unsaturated monocarboxylic acids (monocarboxylic acids having an ethylenically unsaturated bond) such as (meth)acrylic acid and crotonic acid; ethylenically unsaturated dicarboxylic acids (dicarboxylic acids having an ethylenically unsaturated bond) such as fumaric acid, itaconic acid, maleic acid and citraconic acid; anhydrides of the 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, more preferably a hydroxyl group-containing monomer.

[0151] The acrylic monomer having a functional group constituting the acrylic polymer (a11) may be used alone or in combination of two or more. When the acrylic monomer having a functional group constituting the acrylic polymer (a11) is two or more, 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 having 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 not having a functional group include alkoxyalkyl group-containing (meth)acrylic acid esters such as methoxymethyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxymethyl (meth)acrylate, and ethoxyethyl (meth)acrylate; (meth)acrylic acid esters having an aromatic group, including (meth)acrylic acid aryl esters such as phenyl (meth)acrylate; non-crosslinkable (meth)acrylamide and derivatives thereof; and (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 constituting the acrylic polymer (a11) may be used alone or in combination of two or more. When the acrylic monomer having no functional group constituting the acrylic polymer (a11) is two or more, 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 alone or in combination of two or more. When the non-acrylic monomer constituting the acrylic polymer (a11) is two or more, the combination and ratio thereof can be selected arbitrarily.

[0157] In the acrylic polymer (a11), the ratio (content) of the amount of the structural unit derived from the acrylic monomer having a functional group 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 ratio is in such a range, the content of the energy ray curable group in the acrylic resin (a1-1) obtained by copolymerization of the acrylic polymer (a11) and the energy ray curable compound (a12) makes it possible to easily adjust the degree of curing of the first cured resin film (r1) to a preferred range.

[0158] The acrylic polymer (a11) constituting the acrylic resin (a1-1) may be used alone or in combination of two or more. When the acrylic polymer (a11) constituting the acrylic resin (a1-1) is two or more, 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 easily 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; an acryloyl monoisocyanate compound obtained by reacting a diisocyanate compound or a polyisocyanate compound with a polyol compound and hydroxyethyl (meth)acrylate, etc. 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, the combination and ratio thereof can be selected arbitrarily.

[0164] In the acrylic resin (a1-1), the content ratio of the energy ray curable group derived from the energy ray curable compound (a12) to the content of the functional group derived from the acrylic polymer (a11) is preferably 20 to 120 mol%, more preferably 35 to 100 mol%, and even more preferably 50 to 100 mol%. When the content ratio is in such a range, the adhesive strength of the first cured resin film (r1) after curing is greater. Therefore, peeling of the first cured resin film (r1) as a protective film can be more easily suppressed. In addition, when the energy ray curable compound (a12) is a monofunctional compound (having one of the above groups in one molecule), the upper limit of the content ratio is 100 mol%, but when the energy ray curable compound (a12) is a polyfunctional compound (having two or more of the above groups in one 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 crosslinked at the group reactive with the crosslinking agent by polymerization of a monomer which does not correspond to any of the above-mentioned monomers described as constituting the acrylic polymer (a11) and has a group reactive with the crosslinking agent, or may be crosslinked at a group reactive with the functional group derived from the energy ray-curable compound (a12).

[0167] The polymer (a1) may be used alone 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 phenol resin having an energy ray-curable group.

[0170] Among the compounds (a2), examples of the low molecular weight compound having an energy ray-curable group include polyfunctional monomers or oligomers, and acrylate compounds having a (meth)acryloyl group are preferred. 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-decane diol di(meth)acrylate, 1,10-decane diol di(meth)acrylate, 1,2-bis[4-((meth)acryloxydiethoxy)phenyl]propane, 1,2-bis[4-((meth)acryloxypolypropoxy)phenyl]propane, 1,3-dimethylphenyl dimethacrylate, 1,4-dimethylphenyl dimethacrylate, 1,5-dimethylphenyl dimethacrylate, 1,6-dimethylphenyl dimethacrylate, 1,7-dimethylphenyl dimethacrylate, 1,8-dimethylphenyl dimethacrylate, 1,9-dimethylphenyl dimethacrylate, 1,10-dimethylphenyl dimethacrylate, 1,2-dimethylphenyl dimethacrylate ... 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;Polyfunctional (meth)acrylates such as tris(2-(meth)acryloxyethyl)isocyanurate, ε-caprolactone-modified tris-(2-(meth)acryloxyethyl)isocyanurate, ethoxylated glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol poly(meth)acrylate, and dipentaerythritol hexa(meth)acrylate; polyfunctional (meth)acrylate oligomers such as urethane (meth)acrylate oligomers;

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

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

[0173] The compound (a2) may be used alone or in combination of two or more. When the compound (a2) is used in combination of two or more, 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 further 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 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 one, for example, a homopolymer of one kind of acrylic monomer, or a copolymer of two or more kinds of acrylic monomers. The acrylic polymer (b-1) may also be a copolymer of one or more kinds of acrylic monomers and one or more kinds of 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 the (meth)acrylic acid alkyl ester 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 isono (meth)acrylate. Examples of the alkyl (meth)acrylate ester include (meth)acrylic acid alkyl esters in which the alkyl group constituting the alkyl ester has a chain structure having 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. The substituted amino group-containing (meth)acrylic acid ester may, for example, be N-methylaminoethyl (meth)acrylate.

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

[0182] An example of the polymer (b) having no energy ray-curable group and at least a portion of which is crosslinked with a crosslinking agent is one 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 that is highly reactive with an isocyanate group is preferred. 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, which has high reactivity with an epoxy group, is preferred. However, from the viewpoint of preventing corrosion of the circuits of the semiconductor wafer or semiconductor chip, 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), it is sufficient to use one or both of the acrylic monomer and the non-acrylic monomer listed as the monomers constituting the polymer (b-1) 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 ratio (content) of the amount of the structural unit derived from the monomer having a reactive functional group 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 ratio is in such a 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 either 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). In addition, the first energy ray-curable resin composition (x1-2-1) may not contain the compound (a2) and 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) having no 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) having no 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 the active ingredients of the first energy ray curable resin composition (x1-2-1). When the content of the energy ray curable component is in such a 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, the photopolymerization initiator, the filler, the coupling agent, the crosslinking agent and the general-purpose additive may each be used alone or in combination of two or more. When using in combination of two or more, the combination and ratio thereof may 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 because the handling property is improved by dilution. 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 using two or more 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 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 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 for constituting the first energy ray curable resin composition (x1-2-1). The order of addition of the components when blending is not particularly limited, and two or more components may be added at the same time. When a solvent is used, the solvent may be used by mixing it with any of the other ingredients to dilute the ingredients in advance, or the solvent may be used by mixing it with any of the other ingredients without diluting them in advance. The method for mixing the ingredients during mixing is not particularly limited, and may be appropriately selected from known methods such as a method of mixing by rotating a stirrer or agitator blades, a method of mixing using a mixer, a method of mixing by adding ultrasonic waves, etc. The temperature and time during addition and mixing of 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 contained in the first support sheet (Y1), and the pressure-sensitive adhesive layer and intermediate layer that may be contained in the first support sheet (Y1) 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 subjecting the polyester to polymerization; polystyrene; polycycloolefins; polyesters such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyethylene isophthalate, polyethylene-2,6-naphthalenedicarboxylate, and wholly aromatic polyesters in which all constituent 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. 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 alone or two or more types 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, the layers may be the same or different from each other, and the combination of the layers is not particularly limited.

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

[0202] The substrate is preferably one having a high thickness accuracy, i.e., one having reduced thickness variation regardless of the location. Among the above-mentioned constituent materials, examples of materials having a high thickness accuracy 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. In addition, 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 the adhesive 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 exhibit adhesive properties when used in combination with other components such as additives, and resins that exhibit adhesive properties 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, the multi-layer structure may be the same or different from each other, and the combination of the multi-layer structure is not particularly limited.

[0209] The thickness of the 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 adhesive layer" means the thickness of the entire adhesive layer, and for example, the thickness of an adhesive layer consisting of multiple layers means the total thickness of all layers constituting the 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 the physical properties before and after curing.

[0211] <Middle Class> The intermediate layer is in the form of a sheet or film, and the material of the intermediate layer is not particularly limited and may be appropriately selected according to the purpose. For example, when the purpose is to suppress the deformation of the first cured resin film (r1) due to the shape of the bumps present on the semiconductor surface being reflected in the protective film covering the semiconductor surface, a preferred material of the intermediate layer is urethane (meth)acrylate, etc., which has high unevenness-following ability and further improves the attachment 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, the multi-layer structure may be the same or different from each other, and the combination of the multi-layer structure 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 from the viewpoint of easily absorbing the effect of relatively high bumps, it is preferably 50 μm to 600 μm, more preferably 70 μm to 500 μm, and even more preferably 80 μm to 400 μm. Here, the "thickness of the intermediate layer" means the thickness of the entire intermediate layer, and for example, the thickness of an intermediate layer consisting of multiple layers means the total thickness of all layers that make up the intermediate layer.

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

[0215] [Method for producing the 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, a 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, it is possible to directly form the first curable resin (x1) by coating the first thermosetting resin composition (x1-1-1) or the first energy ray curable resin composition (x1-2-1) on the pressure-sensitive adhesive layer. 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] In this way, when forming a continuous two-layer laminate structure using any of the compositions, it is possible to form a new layer by coating the composition on the layer formed from the composition. However, it is preferable that the layer to be laminated later among these two layers is formed in advance on another release film using the composition, and the exposed surface of the formed layer opposite to 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. At this time, it is preferable that the composition is coated on the release-treated surface of the release film. After the formation of the laminate structure, the release film may be removed as necessary.

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

[0219] (Colorant (J)) Here, from the viewpoint of improving the visibility of the marking formed by laser marking, and from the viewpoint of making grinding marks on the back surface of the semiconductor chip less visible to improve the design of the semiconductor chip, 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, squalium-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, triarylmethane-based dyes, anthraquinone-based dyes, naphthol-based dyes, azomethine-based dyes, benzimidazolone-based dyes, pyranthrone-based dyes, and threne-based colors. 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 composition for forming the second curable resin (x2) may be one type or two or more types. When the colorant (J) is two or more types, the combination and ratio thereof can be selected arbitrarily. When using the colorant (J), 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, and the visibility of the print can be adjusted by adjusting the content of the colorant (J) in the second curable resin (x2) and adjusting the light transmittance of the protective film. In addition, by adjusting the content of the colorant (J), the design of the protective film can be improved and the grinding marks on the back surface of the semiconductor wafer can be made 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 solid content of 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 more than the lower limit, the effect of using the colorant (J) is more remarkable. In addition, 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 division 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 division lines.

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

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

[0224] 1. Preparation of wafers for semiconductor chip fabrication A 12-inch silicon wafer (wafer thickness 775 μm) half-cut along the planned dividing lines was used as a wafer for manufacturing semiconductor chips. The width of the half-cut portion of the silicon wafer (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 layer (X1) of a first hardening resin (x1) having a thickness of 90 μm was laminated as a first support sheet (Y1) on the front side (half-cut forming surface) of a wafer for manufacturing semiconductor chips, with the first hardening resin (x1) side as the attachment surface, while being pressed under the following conditions. - 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) having a thickness of 100 μm were laminated to prepare a layer (X1) of the first curable resin (x1) having a thickness of 1 mm. Next, this first curable resin (x1) was cut into a disk shape having 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 of the shear viscosity measuring device: dynamic viscoelasticity measuring device (ARES; manufactured by TA Instruments) was kept warm at 90 ° C. in advance, the test piece was placed on this installation location, and the test piece was fixed and installed at the installation location by pressing a measuring tool against the upper surface of the test piece. Next, a strain of 400% was generated in the test piece under the 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 components 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 type 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 ("EPICLON HP-7200" manufactured by DIC Corporation); weight average molecular weight = 600 Heat hardener Heat curing agent (B2)-1: Novolac type phenolic resin ("BRG-556" manufactured by Showa Denko K.K.) ·Cure accelerator Curing accelerator (C)-1: 2-phenyl-4,5-dihydroxymethylimidazole ("Curezol 2PHZ-PW" manufactured by Shikoku Chemical Industry Co., Ltd.) ·Filling material Filler (D)-1: Spherical silica modified with an epoxy group ("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 solid content 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) in which one side of a polyethylene terephthalate film had been subjected to a silicone treatment for release, and the applied surface was 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 backgrind tape, to obtain a first laminate (α1) in which the backgrind 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 and form 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 which 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 backside observation result, and FIG. 14 shows the cross-sectional polishing observation result. From both results, it was confirmed that the embedding property of the first cured resin film (r1) in the groove portion 13 was good. Furthermore, from the cross-sectional polishing observation result, it was confirmed that the coverage of the first cured resin film (r1) on the wafer front surface was also good. From these results, it was confirmed that the manufacturing method of the present invention makes it possible to obtain a semiconductor chip in which the bump formation surface and side surfaces are well covered with the first cured resin film (r1). [Explanation of symbols]

[0232] 10. Wafers for semiconductor chip manufacturing 11 Wafer 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 Middle 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 bumps are formed, the bump-forming surface having grooves formed thereon as planned division lines not reaching the rear surface of the semiconductor wafer. Step (S2): A step of pressing and pasting a first hardening resin (x1) onto the bump formation surface of the semiconductor chip fabrication wafer to cover the bump formation 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 production wafer having 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 division lines to obtain semiconductor chips having at least the bump formation surface and side surfaces covered with the first cured resin film (r1). The method for producing 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 The step (S2) is carried out 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 on the bump formation surface of the semiconductor chip production wafer, with the layer (X1) serving as an attachment surface; a grinding amount when grinding the back surface of the semiconductor chip fabrication wafer in the step (S-BG) 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 with the first cured resin film (r1) that is formed in the groove portion along the planned division 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 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), 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 backgrind 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 backgrind sheet (b-BG) attached, and then peeling off the backgrind 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 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 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 according to claim 1, wherein the step (S4) is performed by making an incision along the planned division line in a portion of the first cured resin film (r1) of the semiconductor chip manufacturing wafer with the first cured resin film (r1) formed in the groove portion, or by forming a modified region along the planned division line, and then, as the step (S-BG), attaching a backgrind 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), and grinding the back surface of the semiconductor chip manufacturing wafer with the backgrind 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. The method for producing 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 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 producing a semiconductor chip according to any one of claims 1 to 8, wherein

10. The method for producing a semiconductor chip according to any one of claims 1 to 9, wherein the layer (X1) has a thickness of 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 producing 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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