Adhesive sheet for fixing a jig, composite sheet for forming a protective film, and method for manufacturing chip with protective film

Abstract

To provide a jig fixture adhesive sheet that is less likely to float from the fixing jig, is less likely to leave adhesive residue on the side of the fixing jig, and can be easily peeled off from the fixing jig after heating when used for manufacturing a chip with a protective film, a protective film forming composite sheet including a jig adhesive layer formed using the jig fixture adhesive sheet, and a manufacturing method of a chip with a protective film.SOLUTION: An jig fixture adhesive sheet (1) used for a protective film forming composite sheet provided with a thermosetting protective film forming film is constituted by laminating a first adhesive layer (161), a core film (162), and a second adhesive layer (163) in this order in the thickness direction, and the core film (162) is made of a non-polyvinyl chloride plastic film, and the jig fixture adhesive sheet (1) has an adhesive strength of 4.0 to 25 N / 25 mm after heating at 130°C for two hours at 180° to SUS304.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a jig fixing pressure-sensitive adhesive sheet, a composite sheet for forming a protective film comprising a pressure-sensitive adhesive layer for a jig formed using the jig fixing pressure-sensitive adhesive sheet, and a method for producing a chip with 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 the face-down method, a semiconductor chip is used that has electrodes such as bumps on its circuit surface, and these electrodes are bonded to a substrate. As a result, the back surface of the semiconductor chip, opposite the circuit surface, may be exposed.

[0003] On the backside of this exposed semiconductor chip, a resin film containing an organic material is formed to prevent cracks from occurring in the semiconductor chip after the dicing process and packaging, and the semiconductor chip is sometimes incorporated into a semiconductor device as a semiconductor chip with a protective film. A composite sheet for forming a protective film, which combines a protective film-forming film and a dicing tape, is used for manufacturing and processing semiconductor chips with a protective film (for example, Patent Document 1).

[0004] For example, the composite sheet 101 for forming a protective film shown in Fig. 2 includes a thermosetting protective film-forming film 13 on a support sheet 10 having a substrate 11, and a jig adhesive layer 16 on an area near the peripheral edge of the thermosetting protective film-forming film 13 for fixing to a fixing jig such as a ring frame. A release film 151 may be laminated on the thermosetting protective film-forming film 13 and the jig adhesive layer 16. The jig adhesive layer 16 may have a multilayer structure in which a first adhesive layer 161, a core film 162, and a second adhesive layer 163 are laminated in this order in the thickness direction. The core film 162 is often made of polyvinyl chloride (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-15456 Summary of the Invention [Problem to be solved by the invention]

[0006] When manufacturing a chip with a protective film using a composite sheet for forming a protective film having a thermosetting protective film-forming film, for example, first, as shown in Figures 5A and 5B, the jig adhesive layer 16 in the composite sheet for forming a protective film 101 is attached to a fixing jig 18, and the thermosetting protective film-forming film 13 in the composite sheet for forming a protective film 101 is attached to the back surface 9b of a work 9 such as a semiconductor wafer, thereby producing a first laminated composite sheet 501 in which the thermosetting protective film-forming film 13 and the work 9 are laminated in this order in the thickness direction on the support sheet 10.

[0007] Next, the first laminated composite sheet 501 is heated while the peripheral edge of the first laminated composite sheet 501 is attached to the fixing jig 18 by the jig adhesive layer 16 (FIG. 5C). This hardens the thermosetting protective film-forming film 13 to form the protective film 13', thereby producing the second laminated composite sheet 502, which is configured by stacking the support sheet 10, the protective film 13', and the workpiece 9 in this order in the thickness direction, as shown in FIG. 5D.

[0008] Next, second laminated composite sheet 502 is cooled, and then, as shown in Fig. 5E, workpiece 9 in second laminated composite sheet 502 is divided on support sheet 10, and protective film 13' is cut. In this way, third laminated composite sheet 503 is produced in which multiple chips 901 with protective film are fixed on support sheet 10.

[0009] Next, as shown in Fig. 5F, the protective film-equipped chips 901 in the third laminate composite sheet 503 are picked up by being separated from the support sheet 10. After all of the desired protective film-equipped chips 901 have been picked up, the fourth laminate composite sheet 504 remaining after the protective film-equipped chips 901 have been separated from the third laminate composite sheet 503 remains attached to the fixing jig 18 by the jig adhesive layer 16, as shown in Fig. 5G. As shown in Fig. 5H, by peeling the fourth laminate composite sheet 504 from the fixing jig 18, the fixing jig 18 can be reused as shown in Fig. 5A.

[0010] Here, polyvinyl chloride used in the core film of the jig adhesive layer 16 has a large environmental impact, and therefore there is a demand to change to a non-polyvinyl chloride material. Furthermore, when a composite sheet for forming a protective film having a conventional thermosetting protective film-forming film is used and the thermosetting protective film-forming film is thermally cured, the adhesive strength between the jig adhesive layer 16 and the fixing jig 18 becomes strong, and when the fourth laminated composite sheet 504 is peeled off from the fixing jig 18, there is a risk of adhesive residue G occurring on the side of the fixing jig 18, as shown in Figure 7. If the composition of the first adhesive layer 161 and the second adhesive layer 163 is adjusted to weaken the adhesive strength between the jig adhesive layer 16 and the fixing jig 18, after heating to harden the thermosetting protective film-forming film, partial peeling and lift F are likely to occur between the jig adhesive layer 16 and the fixing jig 18, as shown in Figure 6.

[0011] The present invention aims to provide a jig fixing adhesive sheet having a non-polyvinyl chloride core film, which is used to form a composite sheet for forming a protective film having an adhesive layer for a jig, and when used to manufacture chips with protective films, the jig fixing adhesive sheet is less likely to lift off the fixing jig after heating, is less likely to leave adhesive residue on the fixing jig side, and can be easily peeled off from the fixing jig; a composite sheet for forming a protective film having an adhesive layer for a jig formed using the jig fixing adhesive sheet; and a method for manufacturing chips with protective films. [Means for solving the problem]

[0012] The present invention provides the following adhesive sheet for fixing a jig, composite sheet for forming a protective film, and method for producing a chip with a protective film.

[0013] [1] A pressure-sensitive adhesive sheet for fixing a jig used in a composite sheet for forming a protective film provided with a thermosetting protective film-forming film, a first pressure-sensitive adhesive layer, a core film, and a second pressure-sensitive adhesive layer laminated in this order in the thickness direction; The core film is made of a non-polyvinyl chloride plastic film, The pressure-sensitive adhesive sheet for jig fixation has a 180° peeling adhesive strength to SUS304 of 4.0 to 25 N / 25 mm after heating at 130° C. for 2 hours. [2] The pressure-sensitive adhesive sheet for fixing a jig according to [1], wherein the constituent material of the core film includes a polyolefin other than polyethylene or a polyolefin-based thermoplastic elastomer. [3] The adhesive sheet for fixing a jig according to [2], wherein the constituent material of the core film includes unstretched polypropylene. [4] The pressure-sensitive adhesive sheet for jig fixation according to any one of [1] to [3], wherein the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer are formed from a pressure-sensitive adhesive composition for jigs containing an acrylic resin, and the weight-average molecular weight of the acrylic resin is 800,000 or more. [5] A composite sheet for forming a protective film, comprising: a support sheet; a thermosetting protective film-forming film provided on one surface of the support sheet; and a jig adhesive layer provided near a peripheral portion on the one surface of the support sheet or on a first surface of the thermosetting protective film-forming film opposite the support sheet, A composite sheet for forming a protective film, wherein the pressure-sensitive adhesive layer for a jig is formed using the pressure-sensitive adhesive sheet for jig fixation according to any one of [1] to [4]. [6] A method for manufacturing a chip with a protective film, the method comprising: A step of attaching the jig adhesive layer in the composite sheet for forming a protective film to a fixing jig and attaching the thermosetting protective film-forming film in the composite sheet for forming a protective film described in [5] to the back surface of the work, thereby producing a first laminated composite sheet in which the thermosetting protective film-forming film and the work are laminated in this order in the thickness direction on the support sheet; a step of heating the first laminated composite sheet with the peripheral edge of the first laminated composite sheet attached to the fixing jig to harden the thermosetting protective film-forming film and form the protective film, thereby producing a second laminated composite sheet configured by stacking the protective film and the workpiece in this order in the thickness direction on the support sheet; dividing the workpiece in the second laminated composite sheet on the support sheet and cutting the protective film to produce a third laminated composite sheet on which a plurality of chips with protective films are fixed on the support sheet; and picking up the protective film-coated chip in the third laminated composite sheet by separating it from the support sheet. [Effects of the Invention]

[0014] According to the present invention, there is provided a jig fixing adhesive sheet having a non-polyvinyl chloride core film, wherein the jig fixing adhesive sheet is used to form a composite sheet for forming a protective film having a jig adhesive layer, and when used to manufacture a chip with a protective film, the jig fixing adhesive sheet is less likely to lift off the fixing jig after heating, is less likely to leave adhesive residue on the fixing jig side, and can be easily peeled off from the fixing jig; a composite sheet for forming a protective film having a jig adhesive layer formed using the jig fixing adhesive sheet; and a method for manufacturing a chip with a protective film. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a cross-sectional view schematically illustrating an example of a pressure-sensitive adhesive sheet for jig fixation according to an embodiment of the present invention. [Figure 2]1 is a cross-sectional view schematically illustrating an example of a composite sheet for forming a protective film according to an embodiment of the present invention. [Figure 3] FIG. 2 is a cross-sectional view schematically showing another example of the composite sheet for forming a protective film according to the embodiment of the present invention. [Figure 4] FIG. 10 is a cross-sectional view schematically showing still another example of the composite sheet for forming a protective film according to an embodiment of the present invention. [Figure 5A] 1A to 1C are cross-sectional views for schematically illustrating a part of an example of a method for manufacturing a chip with a protective film according to an embodiment of the present invention. [Figure 5B] 1A to 1C are cross-sectional views for schematically illustrating a part of an example of a method for manufacturing a chip with a protective film according to an embodiment of the present invention. [Figure 5C] 1A to 1C are cross-sectional views for schematically illustrating a part of an example of a method for manufacturing a chip with a protective film according to an embodiment of the present invention. [Figure 5D] 1A to 1C are cross-sectional views for schematically illustrating a part of an example of a method for manufacturing a chip with a protective film according to an embodiment of the present invention. [Figure 5E] 1A to 1C are cross-sectional views for schematically illustrating a part of an example of a method for manufacturing a chip with a protective film according to an embodiment of the present invention. [Figure 5F] 1A to 1C are cross-sectional views for schematically illustrating a part of an example of a method for manufacturing a chip with a protective film according to an embodiment of the present invention. [Figure 5G] 1A to 1C are cross-sectional views for schematically illustrating a part of an example of a method for manufacturing a chip with a protective film according to an embodiment of the present invention. [Figure 5H] 1A to 1C are cross-sectional views for schematically illustrating a part of an example of a method for manufacturing a chip with a protective film according to an embodiment of the present invention. [Figure 6] 10A and 10B are cross-sectional views for schematically explaining a part of an example of a conventional method for manufacturing a chip with a protective film. [Figure 7] 10A and 10B are cross-sectional views for schematically explaining a part of an example of a conventional method for manufacturing a chip with a protective film. DETAILED DESCRIPTION OF THE INVENTION

[0016] <<Adhesive sheet for fixing jigs>> The adhesive sheet for jig fixation according to an embodiment of the present invention is an adhesive sheet for jig fixation used in a composite sheet for protective film formation that includes a thermosetting protective film-forming film, and is configured by laminating a first adhesive layer, a core film, and a second adhesive layer in this order in the thickness direction.

[0017] An example of the jig-fixing pressure-sensitive adhesive sheet of this embodiment will be described below with reference to the drawings.

[0018] 1 is a cross-sectional view schematically illustrating an example of the pressure-sensitive adhesive sheet for jig fixation according to the present embodiment. Note that the drawings used in the following description may show enlarged essential parts for the sake of convenience in order to make the features of the present invention easier to understand, and the dimensional ratios of the components may not necessarily be the same as in reality.

[0019] The adhesive sheet for fixing a jig shown in Figure 1 comprises a core film 162, a first adhesive layer 161 and a second adhesive layer 163 laminated on both sides of the core film 162, and further comprises a first release film 151 and a second release film 152 laminated on both outer sides of the first adhesive layer 161 and the second adhesive layer 163.

[0020] The adhesive sheet for fixing a jig shown in Figure 1 can be cut out into a ring shape, for example, as described below, to form an adhesive layer for a jig 16 consisting of a first adhesive layer 161, a core film 162, and a second adhesive layer 163, and can be used for a composite sheet for forming a protective film 101, a composite sheet for forming a protective film 102, and a composite sheet for forming a protective film 104, each of which has a thermosetting protective film-forming film, as shown in Figures 2 to 4.

[0021] The core film is made of a plastic film that is not made of polyvinyl chloride, which reduces the environmental impact.

[0022] The jig fixing pressure-sensitive adhesive sheet has a 180° peeling adhesive strength against SUS304 of 4.0 to 25 N / 25 mm after heating at 130°C for 2 hours. The 180° peeling adhesive strength against SUS304 after heating at 130°C for 2 hours is 4.0 N / 25 mm or more, preferably 5.0 N / 25 mm or more, more preferably 6.0 N / 25 mm or more, and even more preferably 7.0 N / 25 mm or more. By making the adhesive strength equal to or greater than the lower limit, when a protective film-forming composite sheet including a jig adhesive layer is formed using the jig fixing pressure-sensitive adhesive sheet and used to manufacture a chip with a protective film, the risk of lifting from the fixing jig after heating to cure the thermosetting protective film-forming film can be reduced.

[0023] The jig fixing adhesive sheet has a 180° peel adhesive strength to SUS304 after heating at 130°C for 2 hours of 25 N / 25 mm or less, preferably 22 N / 25 mm or less, more preferably 20 N / 25 mm or less, and even more preferably 18 N / 25 mm or less. By making the adhesive strength below the upper limit, when the jig fixing adhesive sheet is used to form a composite sheet for forming a protective film comprising an adhesive layer for a jig and used to manufacture a chip with a protective film, adhesive residue is less likely to remain on the fixing jig and the sheet can be easily peeled from the fixing jig.

[0024] (Method of measuring adhesive strength by 180° peeling after heating at 130°C for 2 hours) The jig fixing adhesive sheet is cut into strips 25 mm wide and 250 mm long, the first adhesive layer 161 on the side to be attached to the fixing jig is exposed, and the exposed first adhesive layer 161 of the jig fixing adhesive sheet is attached to a mirror-finished SUS304 board by rolling a 2 kg roller back and forth once. The sheet is heated to 130°C for 2 hours, allowed to cool, and then measured for 180° peeling adhesive strength at a rate of 300 mm / min in accordance with JIS Z0237 in an environment of 23°C and 50% RH.

[0025] The 180° peeling adhesive strength of the jig fixing adhesive sheet may be measured by exposing the first adhesive layer 161 of the jig fixing adhesive sheet and measuring the 180° peeling adhesive strength on the first adhesive layer 161 side of the jig fixing adhesive sheet, or by exposing the second adhesive layer 163 and measuring the 180° peeling adhesive strength on the second adhesive layer 163 side of the jig fixing adhesive sheet. It is sufficient that either the 180° peeling adhesive strength on the first adhesive layer 161 side or the 180° peeling adhesive strength on the second adhesive layer 163 side of the jig fixing adhesive sheet is within the above-mentioned range, and it is preferable that both the 180° peeling adhesive strength on the first adhesive layer 161 side and the 180° peeling adhesive strength on the second adhesive layer 163 side of the jig fixing adhesive sheet are within the above-mentioned range.

[0026] The jig fixing pressure-sensitive adhesive sheet preferably has a 180° peel adhesive strength to SUS304 before heating of 2.0 N / 25 mm or more, more preferably 2.5 N / 25 mm or more, and even more preferably 3.0 N / 25 mm or more. By making the adhesive strength equal to or greater than the lower limit, it is possible to maintain an appropriate adhesive strength with the fixing jig when the jig fixing pressure-sensitive adhesive sheet is used to form a composite sheet for forming a protective film comprising a pressure-sensitive adhesive layer for a jig and used to manufacture a chip with a protective film.

[0027] The jig fixing adhesive sheet preferably has a 180° peeling adhesive strength to SUS304 before heating of 20 N / 25 mm or less, more preferably 17 N / 25 mm or less, and even more preferably 14 N / 25 mm or less. By making the adhesive strength below the upper limit, when the jig fixing adhesive sheet is used to form a composite sheet for forming a protective film comprising an adhesive layer for a jig and used to manufacture a chip with a protective film, adhesive residue is less likely to remain on the fixing jig and the sheet can be easily peeled from the fixing jig.

[0028] (Method for measuring 180° peeling adhesive strength before heating) The jig fixing adhesive sheet is cut into strips 25 mm wide and 250 mm long, the first adhesive layer 161 is exposed, and the exposed first adhesive layer 161 of the jig fixing adhesive sheet is attached to a mirror-finished SUS304 sheet by rolling a 2 kg roller back and forth once. 30 minutes after attachment, the 180° peeling adhesive strength is measured at a rate of 300 mm / min in accordance with JIS Z0237 in an environment of 23°C and 50% RH.

[0029] Next, each layer constituting the jig-fixing pressure-sensitive adhesive sheet will be described in more detail.

[0030] <Core film> The core film is made of a non-polyvinyl chloride plastic film. The material of the core film is not limited as long as it is not polyvinyl chloride, and examples thereof include various resins. Examples of the resin include polyethylenes such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and high-density polyethylene (HDPE); polyolefins other than polyethylene such as polypropylene, polybutene, polybutadiene, polymethylpentene, and norbornene resin; polyolefin-based thermoplastic elastomers such as ethylene-propylene rubber; 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; Examples of such polyesters include styrene; polycycloolefins; polyesters such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyethylene isophthalate, polyethylene-2,6-naphthalenedicarboxylate, and wholly aromatic polyesters in which all structural units have aromatic cyclic groups; copolymers of two or more of the above polyesters; poly(meth)acrylic acid esters; polyurethanes; polyurethane acrylates; polyimides; polyamides; polycarbonates; fluororesins; polyacetals; modified polyphenylene oxides; polyphenylene sulfides; polysulfones; and polyether ketones.

[0031] Among these, the constituent material of the core film preferably contains a polyolefin other than polyethylene or a polyolefin-based thermoplastic elastomer, and more preferably contains unstretched polypropylene, since this reduces the risk of the film warping and lifting due to heat treatment.

[0032] The resin constituting the core film may be one type only, or two or more types, and when two or more types are used, the combination and ratio thereof can be selected arbitrarily.

[0033] The core film may consist of one layer (single layer) or two or more layers. If it consists of multiple layers, these layers may be the same or different from each other, and the combination of these layers is not particularly limited.

[0034] The thickness of the core film is preferably 16 to 100 μm, more preferably 20 to 80 μm, and even more preferably 24 to 60 μm. When the thickness of the core film is within this range, the flexibility of the pressure-sensitive adhesive sheet for jig fixation is improved, and the occurrence of wrinkles in the composite sheet for forming a protective film using the pressure-sensitive adhesive sheet for jig fixation can be prevented. Here, "thickness of core film" means the thickness of the entire core film; for example, the thickness of a core film consisting of multiple layers means the total thickness of all layers that make up the core film.

[0035] The core film is preferably transparent, and may be colored or have other layers vapor-deposited thereon depending on the purpose.

[0036] In order to adjust the adhesion between the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer provided on both sides of the core film, the surface of the core film may be subjected to roughening treatment such as sandblasting or solvent treatment; oxidation treatment such as corona discharge treatment, electron beam irradiation treatment, plasma treatment, ozone or ultraviolet irradiation treatment, flame treatment, chromic acid treatment, or hot air treatment; lipophilic treatment; hydrophilic treatment; etc. The surface of the core film may also be treated with a primer.

[0037] The core film may contain a specific range of components (for example, resin, etc.) to have adhesiveness on at least one surface.

[0038] ○Method of manufacturing core film The core film can be produced by a known method. For example, a core film containing a resin can be produced by molding a resin composition containing the core film.

[0039] <First Pressure-Sensitive Adhesive Layer and Second Pressure-Sensitive Adhesive Layer> The first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer satisfy the above-mentioned peel adhesive strength requirements and may be non-energy ray curable or energy ray curable, preferably non-energy ray curable. In this specification, "non-energy ray curable" means a property that does not cure even when irradiated with energy rays. Conversely, a property that cures when irradiated with energy rays is called "energy ray curable". As used herein, "energy rays" refers to electromagnetic waves or charged particle beams that have an energy quantum. Examples of energy rays include ultraviolet rays, radioactive rays, and electron beams. Ultraviolet rays can be irradiated using, for example, a high-pressure mercury lamp, a fusion lamp, a xenon lamp, a black light, or an LED lamp as an ultraviolet light source. Electron beams can be irradiated using those generated by an electron beam accelerator or the like.

[0040] The thickness of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is preferably 2 to 15 μm, more preferably 3 to 12 μm, and particularly preferably 4 to 10 μm, respectively, since this allows the 180° peeling adhesive strength to be appropriately adjusted.

[0041] The total thickness of the first pressure-sensitive adhesive layer, core film, and second pressure-sensitive adhesive layer is preferably 25 to 70 μm, more preferably 30 to 65 μm, and even more preferably 35 to 60 μm. By being equal to or greater than the lower limit, the 180° peel adhesive strength can be appropriately adjusted, and by being equal to or less than the upper limit, the flexibility of the pressure-sensitive adhesive sheet for jig fixation is improved, and the occurrence of wrinkles in a composite sheet for forming a protective film using the pressure-sensitive adhesive sheet for jig fixation can be prevented.

[0042] The first and second pressure-sensitive adhesive layers can be formed using a pressure-sensitive adhesive composition for a jig containing a pressure-sensitive adhesive. For example, the first pressure-sensitive adhesive layer can be formed at the desired location by applying the pressure-sensitive adhesive composition for a jig to the surface on which the first pressure-sensitive adhesive layer is to be formed and drying as necessary. The second pressure-sensitive adhesive layer can be formed at the desired location by applying the pressure-sensitive adhesive composition for a jig to the surface on which the second pressure-sensitive adhesive layer is to be formed and drying as necessary. More specific methods for forming the first and second pressure-sensitive adhesive layers will be described in detail below, along with methods for forming other layers. The ratio of the contents of the components that do not vaporize at room temperature in the pressure-sensitive adhesive composition for a jig is usually the same as the ratio of the contents of the components in the pressure-sensitive adhesive layer.

[0043] The pressure-sensitive adhesive composition for a jig may be applied by a known method, for example, a method using various coaters such as an air knife coater, a blade coater, a bar coater, a gravure coater, a roll coater, a roll knife coater, a curtain coater, a die coater, a knife coater, a screen coater, a Mayer bar coater, or a kiss coater.

[0044] The drying conditions for the pressure-sensitive adhesive composition for a jig are not particularly limited. However, when the pressure-sensitive adhesive composition for a jig contains a solvent described below, it is preferable to heat-dry it. In this case, it is preferable to dry it, for example, at 70 to 130°C for 10 seconds to 5 minutes.

[0045] The pressure-sensitive adhesive composition for a jig used to form the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer may be a non-energy ray-curable pressure-sensitive adhesive composition or an energy ray-curable pressure-sensitive adhesive composition described below, and is preferably a non-energy ray-curable pressure-sensitive adhesive composition.

[0046] Here, examples of non-energy ray-curable pressure-sensitive adhesive compositions include those containing adhesive resins (hereinafter referred to as "adhesive resin (i)") such as acrylic resins (resins containing structural units derived from (meth)acrylic acid esters), urethane-based resins (resins having urethane bonds), rubber-based resins (resins having rubber structures), silicone-based resins (resins having siloxane bonds), epoxy-based resins (resins having epoxy groups), polyvinyl ethers, or polycarbonates.

[0047] (Adhesive resin (i)) Among the adhesive resins (i), acrylic resins are preferred because they have high adhesion to a fixing jig 18 such as a ring frame and can effectively prevent the composite sheet for forming a protective film from peeling off from the fixing jig 18 during a dicing process or the like. Examples of the acrylic resin in the adhesive resin (i) include acrylic polymers having at least a structural unit derived from a (meth)acrylic acid alkyl ester. The acrylic resin may have one type of structural unit or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0048] The (meth)acrylic acid alkyl ester may be, for example, one in which the alkyl group constituting the alkyl ester has 1 to 20 carbon atoms, and the alkyl group is preferably linear or branched. More specifically, the (meth)acrylic acid alkyl esters include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-butyl (meth)acrylate, -nonyl, isononyl (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, octadecyl (meth)acrylate (stearyl (meth)acrylate), nonadecyl (meth)acrylate, and eicosyl (meth)acrylate.

[0049] In terms of improving the adhesive strength of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer, the acrylic polymer preferably has a structural unit derived from a (meth)acrylic acid alkyl ester in which the alkyl group has 4 or more carbon atoms. In terms of further improving the adhesive strength of the pressure-sensitive adhesive layer, the alkyl group preferably has 4 to 12 carbon atoms, and more preferably 4 to 8 carbon atoms. Furthermore, the (meth)acrylic acid alkyl ester in which the alkyl group has 4 or more carbon atoms is preferably an acrylic acid alkyl ester.

[0050] The acrylic polymer preferably further contains a structural unit derived from a functional group-containing monomer in addition to the structural unit derived from the (meth)acrylic acid alkyl ester. Examples of the functional group-containing monomer include those whose functional group reacts with a crosslinking agent described below to become a crosslinking starting point, and those whose functional group reacts with a functional group such as an isocyanate group or a glycidyl group in an unsaturated group-containing compound to enable the introduction of an unsaturated group into a side chain of an acrylic polymer.

[0051] Examples of the functional group in the functional group-containing monomer include a hydroxyl group, a carboxyl group, an amino group, and an epoxy group. That is, examples of functional group-containing monomers include hydroxyl group-containing monomers, carboxyl group-containing monomers, amino group-containing monomers, and epoxy group-containing monomers.

[0052] Examples of the hydroxyl group-containing monomer include hydroxyalkyl (meth)acrylates such as hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; and non-(meth)acrylic unsaturated alcohols (unsaturated alcohols not having a (meth)acryloyl skeleton) such as vinyl alcohol and allyl alcohol. Because the crosslinking reaction is facilitated, 4-hydroxybutyl (meth)acrylate or 2-hydroxyethyl (meth)acrylate is preferred, 4-hydroxybutyl acrylate or 2-hydroxyethyl acrylate is more preferred, and 4-hydroxybutyl acrylate is particularly preferred.

[0053] Examples of the carboxy group-containing monomer include ethylenically unsaturated monocarboxylic acids (monocarboxylic acids having an ethylenically unsaturated bond) such as (meth)acrylic acid and crotonic acid; ethylenically unsaturated dicarboxylic acids (dicarboxylic acids having an ethylenically unsaturated bond) such as fumaric acid, itaconic acid, maleic acid and citraconic acid; anhydrides of the ethylenically unsaturated dicarboxylic acids; and (meth)acrylic acid carboxyalkyl esters such as 2-carboxyethyl methacrylate.

[0054] The functional group-containing monomer is preferably a hydroxyl group-containing monomer or a carboxyl group-containing monomer, and more preferably a hydroxyl group-containing monomer.

[0055] The acrylic resin in the adhesive resin (i) is preferably an acrylic polymer having a structural unit derived from a (meth)acrylic acid alkyl ester and a structural unit derived from a hydroxyl group-containing monomer, and may be an acrylic polymer having a structural unit derived from a (meth)acrylic acid alkyl ester, a structural unit derived from a hydroxyl group-containing monomer, and a structural unit derived from a carboxyl group-containing monomer.

[0056] The functional group-containing monomer constituting the acrylic polymer may be of only one type or of two or more types, and when two or more types are used, the combination and ratio thereof can be selected arbitrarily.

[0057] In the acrylic polymer, the content of the structural units derived from functional group-containing monomers is preferably 0.5 to 12 mass%, more preferably 0.8 to 10 mass%, and particularly preferably 1.0 to 5.0 mass%, relative to the total amount of structural units.

[0058] The acrylic polymer may further contain structural units derived from other monomers in addition to the structural units derived from the (meth)acrylic acid alkyl ester and the structural units derived from the functional group-containing monomer. The other monomer is not particularly limited as long as it is copolymerizable with the (meth)acrylic acid alkyl ester or the like. Examples of the other monomers include styrene, α-methylstyrene, vinyltoluene, vinyl formate, vinyl acetate, acrylonitrile, and acrylamide.

[0059] The other monomers constituting the acrylic polymer may be one type only or two or more types, and when two or more types are used, the combination and ratio thereof can be selected arbitrarily.

[0060] The weight-average molecular weight (Mw) of the acrylic resin in the adhesive resin (i) is preferably 300,000 or more, more preferably 500,000 or more, and particularly preferably 800,000 or more. By having a weight-average molecular weight (Mw) equal to or greater than the lower limit, when the jig fixing adhesive sheet is used to form a composite sheet for forming a protective film comprising a jig adhesive layer and used to manufacture a chip with a protective film, adhesive residue is less likely to remain on the fixing jig, and the sheet can be easily peeled off from the fixing jig.

[0061] The weight-average molecular weight of the acrylic resin in the adhesive resin (i) is preferably 10 million or less, more preferably 5 million or less, and even more preferably 2 million or less. By having a weight-average molecular weight equal to or less than the upper limit, when the adhesive sheet for jig fixing is used to form a composite sheet for forming a protective film having an adhesive layer for a jig and used to manufacture a chip with a protective film, it becomes easy to prevent the composite sheet from lifting off the fixing jig after heating.

[0062] In this specification, unless otherwise specified, the weight average molecular weight refers to a polystyrene equivalent value measured by gel permeation chromatography (GPC).

[0063] The glass transition temperature (Tg) of the acrylic resin in the adhesive resin (i) is preferably −70 to 30° C., more preferably −60 to 20° C. When the Tg of the acrylic resin is within this range, a jig fixing adhesive sheet can be easily obtained that, when used to manufacture a chip with a protective film, is less likely to lift off the fixing jig after heating and leaves less adhesive residue on the fixing jig side.

[0064] The glass transition temperature (Tg) of an acrylic resin can be calculated using the Fox formula shown below. 1 / Tg=(W1 / Tg1)+(W2 / Tg2)+...+(Wm / Tgm) (where Tg is the glass transition temperature of the acrylic resin, Tg1, Tg2,...Tgm are the glass transition temperatures of the homopolymers of the monomers that are the raw materials for the acrylic resin, and W1, W2,...Wm are the mass fractions of the monomers, respectively. However, W1+W2+...+Wm=1.) The glass transition temperatures of the homopolymers of each monomer in the Fox formula can be found in the Polymer Data Handbook or the Adhesive Handbook. For example, the Tg of methyl acrylate homopolymer is 10°C, and the Tg of 2-hydroxyethyl acrylate homopolymer is -15°C.

[0065] The adhesive resin (i) other than the acrylic polymer also preferably has a structural unit derived from a functional group-containing monomer, similar to the acrylic polymer.

[0066] The adhesive resin (i) contained in the pressure-sensitive adhesive composition for a jig may be one type only, or two or more types, and when two or more types are contained, the combination and ratio thereof can be selected arbitrarily.

[0067] In the pressure-sensitive adhesive composition for jigs, the ratio of the content of the adhesive resin (i) to the total content of components other than the solvent (i.e., the content of the adhesive resin (i) in the pressure-sensitive adhesive layer) is preferably 60 to 99 mass%, more preferably 70 to 98 mass%, and particularly preferably 80 to 96 mass%. When the content of the adhesive resin (i) is within this range, the adhesiveness of the pressure-sensitive adhesive layer becomes better.

[0068] (Crosslinking agent (ii)) The pressure-sensitive adhesive composition for a jig preferably contains a crosslinking agent (ii). The crosslinking agent (ii) reacts with the functional group to crosslink the adhesive resins (i) together, for example. Examples of the crosslinking agent (ii) include isocyanate-based crosslinking agents (crosslinking agents having an isocyanate group) such as tolylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, and adducts of these diisocyanates; epoxy-based crosslinking agents (crosslinking agents having a glycidyl group) such as ethylene glycol glycidyl ether; aziridine-based crosslinking agents (crosslinking agents having an aziridinyl group) such as hexa[1-(2-methyl)-aziridinyl]triphosphatriazine; metal chelate-based crosslinking agents (crosslinking agents having a metal chelate structure) such as aluminum chelate; and isocyanurate-based crosslinking agents (crosslinking agents having an isocyanuric acid skeleton). The crosslinking agent (ii) is preferably an isocyanate-based crosslinking agent, from the viewpoints of improving the cohesive strength of the pressure-sensitive adhesive and thereby improving the adhesive strength of the pressure-sensitive adhesive layer, and of easy availability.

[0069] The crosslinking agent (ii) contained in the pressure-sensitive adhesive composition for jigs may be one type only, or two or more types, and when two or more types are contained, the combination and ratio thereof can be selected arbitrarily.

[0070] When the pressure-sensitive adhesive composition for jigs contains a crosslinking agent (ii), the content of the crosslinking agent (ii) in the pressure-sensitive adhesive composition for jigs is preferably 0.02 to 4.0 parts by mass, more preferably 0.04 to 2.0 parts by mass, and particularly preferably 0.08 to 1.5 parts by mass, per 100 parts by mass of the pressure-sensitive adhesive resin (i). When the content of the crosslinking agent (ii) is equal to or greater than the lower limit, the effect of using the crosslinking agent (ii) is more pronounced. Furthermore, when the content of the crosslinking agent (ii) is equal to or less than the upper limit, it becomes easier to adjust the adhesive strength of the pressure-sensitive adhesive layer to the protective film-forming film and the protective film.

[0071] (Other additives) The pressure-sensitive adhesive composition for jigs may contain other additives that do not fall under any of the above-mentioned components, within the range that does not impair the effects of the present invention. Examples of the other additives include known additives such as antistatic agents, antioxidants, softeners (plasticizers), fillers, rust inhibitors, colorants (pigments, dyes), sensitizers, tackifiers, reaction retarders, and crosslinking accelerators (catalysts). The reaction retarder is, for example, a retarder that inhibits the progress of an unintended crosslinking reaction in the pressure-sensitive adhesive composition for jigs during storage due to the action of a catalyst mixed in the pressure-sensitive adhesive composition for jigs. Examples of the reaction retarder include those that form a chelate complex by chelating with the catalyst, and more specifically, those having two or more carbonyl groups (-C(=O)-) in one molecule.

[0072] The other additives contained in the pressure-sensitive adhesive composition for jigs may be one kind or two or more kinds, and when there are two or more kinds, the combination and ratio thereof can be selected arbitrarily.

[0073] In the pressure-sensitive adhesive composition for a jig, the content of other additives is not particularly limited, and may be selected appropriately depending on the type of additive.

[0074] (solvent) The pressure-sensitive adhesive composition for a jig may contain a solvent. When the pressure-sensitive adhesive composition for a jig contains a solvent, the suitability for application to a surface to be coated is improved.

[0075] The solvent is preferably an organic solvent, and examples of the organic solvent include ketones such as methyl ethyl ketone and acetone; esters (carboxylic acid esters) such as ethyl acetate; ethers such as tetrahydrofuran and dioxane; aliphatic hydrocarbons such as cyclohexane and n-hexane; aromatic hydrocarbons such as toluene and xylene; and alcohols such as 1-propanol and 2-propanol.

[0076] As the solvent, for example, the solvent used in the production of the adhesive resin (i) may be used as it is in the adhesive composition for a jig without being removed from the adhesive resin (i), or a solvent of the same or different type as that used in the production of the adhesive resin (i) may be added separately during the production of the adhesive composition for a jig.

[0077] The pressure-sensitive adhesive composition for a jig may contain only one type of solvent, or two or more types of solvents. When two or more types of solvents are contained, the combination and ratio thereof can be selected arbitrarily.

[0078] In the pressure-sensitive adhesive composition for a jig, the content of the solvent is not particularly limited and may be adjusted appropriately.

[0079] [Method of manufacturing adhesive composition for jig] The pressure-sensitive adhesive composition for a jig can be obtained by blending the components that constitute the composition. The order of addition of the components when blending is not particularly limited, and two or more components may be added simultaneously. When a solvent is used, the solvent may be mixed with any of the ingredients other than the solvent to pre-dilute the ingredients, or the solvent may be mixed with any of the ingredients other than the solvent without pre-diluting these ingredients.

[0080] The method for mixing the components during blending is not particularly limited, and may be appropriately selected from known methods such as a method of mixing by rotating a stirrer or stirring blades, a method of mixing using a mixer, or a method of mixing by adding ultrasound. The temperature and time for adding and mixing each component are not particularly limited as long as the components do not deteriorate, and may be adjusted appropriately. A temperature of 15 to 30°C is preferred.

[0081] <First release film and second release film> The jig fixing pressure-sensitive adhesive sheet can be supplied in a form in which a first release film and a second release film are laminated on both outer surfaces of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer.

[0082] The first release film and the second release film are not particularly limited, and commercially available release films can be used, such as polyethylene films, polypropylene films, polybutene films, polybutadiene films, polymethylpentene films, polyvinyl chloride films, vinyl chloride copolymer films, polyethylene terephthalate films, polyethylene naphthalate films, polybutylene terephthalate films, polyurethane films, ethylene-vinyl acetate copolymer films, ionomer resin films, ethylene-(meth)acrylic acid copolymer films, ethylene-(meth)acrylic acid ester copolymer films, polystyrene films, polycarbonate films, polyimide films, and fluororesin films. Crosslinked films of these films can also be used. Laminated films of these films can also be used.

[0083] The surface tension of the surface of the first release film in contact with the first pressure-sensitive adhesive layer and the surface of the second release film in contact with the second pressure-sensitive adhesive layer is preferably 40 mN / m or less, more preferably 37 mN / m or less, and particularly preferably 35 mN / m or less. The lower limit is usually about 25 mN / m. Release films with such relatively low surface tensions can be obtained by appropriately selecting the material, or by applying a release agent to the surface of the release film and performing a release treatment. The surface tensions of the surface of the first release film in contact with the first pressure-sensitive adhesive layer and the surface of the second release film in contact with the second pressure-sensitive adhesive layer may be the same, or preferably they are different, for example, so that the surface of the first release film in contact with the first pressure-sensitive adhesive layer is a light-release surface.

[0084] The release agent used in the release treatment may be an alkyd-based, silicone-based, fluorine-based, unsaturated polyester-based, polyolefin-based, wax-based, or rubber-based release agent, but the alkyd-based, silicone-based, and fluorine-based release agents are particularly preferred because of their heat resistance.

[0085] To use the above-mentioned release agent to perform a release treatment on the surface of a film or the like that will serve as the base for the first release film and the second release film, the release agent can be applied directly without solvent, or diluted with a solvent or made into an emulsion, using a gravure coater, Mayer bar coater, air knife coater, roll coater, or the like, and the release film to which the release agent has been applied can be left at room temperature or under heat, or cured with an electron beam to form a release agent layer.

[0086] The surface roughness (Ra) of the surface of the first release film in contact with the first pressure-sensitive adhesive layer and the surface of the second release film in contact with the second pressure-sensitive adhesive layer is preferably 10 to 100 nm, more preferably 15 to 60 nm, and even more preferably 20 to 50 nm. The surface roughness (Ra) of the surface of the first release film in contact with the first pressure-sensitive adhesive layer and the surface of the second release film in contact with the second pressure-sensitive adhesive layer may be the same or different.

[0087] <Method of manufacturing the adhesive sheet for fixing a jig> The jig-fixing pressure-sensitive adhesive sheet can be produced by laminating the above-mentioned layers in order so that they are in a corresponding positional relationship. The method for forming each layer is as described above.

[0088] For example, a pressure-sensitive adhesive composition for a jig for a first pressure-sensitive adhesive layer is applied to the release-treated surface of a first release film, and a first pressure-sensitive adhesive layer is formed on the release-treated surface of the first release film. The exposed surface of the first pressure-sensitive adhesive layer is bonded to one first surface of a core film. The pressure-sensitive adhesive composition for a jig for a second pressure-sensitive adhesive layer is applied to the release-treated surface of a second release film, and a second pressure-sensitive adhesive layer is formed on the release-treated surface of the second release film. By bonding the exposed surface of the second pressure-sensitive adhesive layer to the other second surface of the core film, a pressure-sensitive adhesive sheet for jig fixation can be produced in which the first pressure-sensitive adhesive layer, core film, and second pressure-sensitive adhesive layer are laminated in this order in the thickness direction.

[0089] <<Composite sheet for forming protective film>> A composite sheet for forming a protective film according to an embodiment of the present invention is a composite sheet for forming a protective film comprising a support sheet, a thermosetting protective film-forming film provided on one side of the support sheet, and a jig adhesive layer provided near the peripheral edge on the one side of the support sheet or on the first side of the thermosetting protective film-forming film opposite the support sheet, wherein the jig adhesive layer is formed using the jig fixing adhesive sheet according to the embodiment of the present invention described above. An example of the composite sheet for forming a protective film according to this embodiment will be described below with reference to the drawings.

[0090] FIG. 2 is a cross-sectional view schematically illustrating an example of the composite sheet for forming a protective film according to the present embodiment. In FIG. 2 and subsequent figures, the same components as those shown in the figures already described are given the same reference numerals as in the figures already described, and detailed description thereof will be omitted.

[0091] The composite sheet 101 for forming a protective film shown here is composed of a support sheet 10 and a thermosetting protective film forming film 13 provided on one side 10a of the support sheet 10 (sometimes referred to as the "first side" in this specification). The support sheet 10 is configured to include a base material 11 and an adhesive layer 12 provided on one surface (first surface) 11a of the base material 11. In the composite sheet 101 for forming a protective film, the adhesive layer 12 is disposed between the base material 11 and the thermosetting protective film-forming film 13. That is, it comprises a support sheet 10 consisting of a base material 11 and an adhesive layer 12, a thermosetting protective film-forming film 13 provided on the surface of the adhesive layer 12 of the support sheet 10, and an adhesive layer 16 for a jig provided near the peripheral portion on a first surface of the thermosetting protective film-forming film 13 opposite the support sheet 10. The first surface 10a of the support sheet 10 is the same as the surface 12a of the pressure-sensitive adhesive layer 12 opposite to the substrate 11 side (sometimes referred to as the "first surface" in this specification).

[0092] The composite sheet for forming a protective film 101 further includes an adhesive layer for a jig 16 and a release film 15 on the thermosetting protective film-forming film 13 . In the composite sheet 101 for forming a protective film, a thermosetting protective film-forming film 13 is laminated over the entire or almost entire first surface 12a of the pressure-sensitive adhesive layer 12, and a jig pressure-sensitive adhesive layer 16 is laminated over a portion of the surface 13a of the thermosetting protective film-forming film 13 opposite the pressure-sensitive adhesive layer 12 side (sometimes referred to as the "first surface" in this specification), i.e., the area near the peripheral portion. Furthermore, a release film 15 is laminated over an area of ​​the first surface 13a of the thermosetting protective film-forming film 13 where the jig pressure-sensitive adhesive layer 16 is not laminated, and over a surface 16a of the jig pressure-sensitive adhesive layer 16 opposite the thermosetting protective film-forming film 13 side (sometimes referred to as the "first surface" in this specification). A support sheet 10 is provided on a surface 13b of the thermosetting protective film-forming film 13 opposite the first surface 13a (sometimes referred to as the "second surface" in this specification).

[0093] Not only in the case of the composite sheet 101 for forming a protective film, but also in the composite sheet for forming a protective film of this embodiment, the release film has an optional configuration, and the composite sheet for forming a protective film of this embodiment may or may not have a release film.

[0094] The composite sheet 101 for forming a protective film is used by removing the release film 15, attaching the back surface of the work to the first surface 13a of the thermosetting protective film-forming film 13, and further attaching the first surface 16a of the jig adhesive layer 16 to a fixing jig 18 such as a ring frame.

[0095] FIG. 3 is a cross-sectional view schematically showing another example of the composite sheet for forming a protective film according to the present embodiment. The composite sheet 102 for forming a protective film shown here is the same as the composite sheet 101 for forming a protective film shown in Figure 2, except that the shape and size of the thermosetting protective film-forming film are different and the adhesive layer for the jig is laminated on the first side of the adhesive layer rather than on the first side of the thermosetting protective film-forming film.

[0096] More specifically, in the composite sheet 102 for forming a protective film, the thermosetting protective film-forming film 23 is laminated in a partial region of the first surface 12a of the pressure-sensitive adhesive layer 12, i.e., in a central region in the width direction (left-right direction in FIG. 3 ) of the pressure-sensitive adhesive layer 12. Furthermore, in a region of the first surface 12a of the pressure-sensitive adhesive layer 12 where the thermosetting protective film-forming film 23 is not laminated, a jig pressure-sensitive adhesive layer 16 is laminated so as to surround the thermosetting protective film-forming film 23 from the outside in the width direction without contacting it. A release film 15 is laminated on a surface 23a of the thermosetting protective film-forming film 23 opposite the pressure-sensitive adhesive layer 12 side (sometimes referred to as the "first surface" in this specification) and on the first surface 16a of the jig pressure-sensitive adhesive layer 16. A support sheet 10 is provided on a surface 23b of the thermosetting protective film-forming film 23 opposite the first surface 23a (sometimes referred to as the "second surface" in this specification).

[0097] FIG. 4 is a cross-sectional view schematically showing still another example of the composite sheet for forming a protective film according to the present embodiment. The composite sheet 104 for forming a protective film shown here is the same as the composite sheet 101 for forming a protective film shown in FIG. 2, except that it is configured to include a support sheet 20 instead of the support sheet 10.

[0098] The support sheet 20 is made of only the substrate 11 . That is, the composite sheet 104 for forming a protective film is constructed by laminating a substrate 11 and a thermosetting protective film-forming film 13 in the thickness direction. The composite sheet 104 includes a support sheet 20 consisting of only the substrate 11, a thermosetting protective film-forming film 13 provided on one side of the support sheet 20, and a jig adhesive layer 16 provided near the peripheral edge on the one side of the support sheet 10. The surface (first surface) 20 a of the support sheet 20 on the thermosetting protective film-forming film 13 side is the same as the first surface 11 a of the base material 11 .

[0099] The composite sheet for forming a protective film of this embodiment is not limited to that shown in Figures 2 to 4, and may be one in which some of the configurations shown in Figures 2 to 4 have been changed or deleted, or one in which other configurations have been added to those described above, within the scope that does not impair the effects of the present invention.

[0100] Next, each layer constituting the composite sheet for forming a protective film will be described in more detail.

[0101] Support sheet The support sheet may consist of one layer (single layer) or two or more layers. When the support sheet consists of multiple layers, the constituent materials and thicknesses of these multiple layers may be the same or different, and the combination of these multiple layers is not particularly limited as long as it does not impair the effects of the present invention.

[0102] The support sheet is preferably transparent, and may be colored depending on the purpose. When the thermosetting protective film-forming film has energy ray curability, the support sheet is preferably one that transmits energy rays.

[0103] Examples of the support sheet include one comprising a substrate and a pressure-sensitive adhesive layer provided on one surface of the substrate, one consisting of only the substrate, etc. When the support sheet comprises a pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer is disposed between the substrate and the thermosetting protective film-forming film in the composite sheet for forming a protective film.

[0104] When a support sheet having a substrate and a pressure-sensitive adhesive layer is used, the adhesion and peelability between the support sheet and the thermosetting protective film-forming film in the composite sheet for forming a protective film can be easily adjusted. When a support sheet consisting of only a substrate is used, a composite sheet for forming a protective film can be produced at low cost.

[0105] ○Base material The substrate is in the form of a sheet or film, and examples of the constituent materials thereof include various resins. Examples of the resin include polyethylenes such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and high-density polyethylene (HDPE); polyolefins other than polyethylene such as polypropylene, polybutene, polybutadiene, polymethylpentene, and norbornene resin; ethylene-based copolymers (copolymers obtained using ethylene as a monomer) such as ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester copolymer, and ethylene-norbornene copolymer; polystyrene; polycycloolefin; polyesters such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyethylene isophthalate, polyethylene-2,6-naphthalenedicarboxylate, and wholly aromatic polyesters in which all structural units have aromatic cyclic groups; copolymers of two or more of the above polyesters; poly(meth)acrylic acid ester; polyurethane; polyurethane acrylate; polyimide; polyamide; polycarbonate; fluororesin; polyacetal; modified polyphenylene oxide; polyphenylene sulfide; polysulfone; and polyether ketone.

[0106] The constituent material of the substrate preferably contains a polyolefin resin, and among these, polyolefins other than polyethylene are preferred, and polypropylene is more preferred.

[0107] Further, examples of the resin include polymer alloys such as mixtures of the polyester and other resins. The polymer alloys of the polyester and other resins preferably contain a relatively small amount of resin other than polyester. Examples of the resin include crosslinked resins in which one or more of the resins exemplified above are crosslinked; and modified resins such as ionomers using one or more of the resins exemplified above.

[0108] The resin constituting the substrate may be one type only, or two or more types, and when two or more types are used, the combination and ratio thereof can be selected arbitrarily.

[0109] The substrate may consist of one layer (single layer), or may consist of two or more layers. When the substrate consists of multiple layers, these multiple layers may be the same or different from each other, and the combination of these multiple layers is not particularly limited.

[0110] The thickness of the substrate is preferably 50 to 300 μm, more preferably 60 to 100 μm. When the thickness of the substrate is within this range, the flexibility of the support sheet and the composite sheet for forming a protective film and the suitability for attachment to a workpiece such as a semiconductor wafer are further improved. Here, the "thickness of the substrate" means the thickness of the entire substrate, and for example, the thickness of a substrate consisting of multiple layers means the total thickness of all layers that make up the substrate.

[0111] The substrate may contain, in addition to the main constituent materials such as the resin, various known additives such as fillers, colorants, antioxidants, organic lubricants, catalysts, and softeners (plasticizers).

[0112] The substrate is preferably transparent, and may be colored depending on the purpose, or may have other layers vapor-deposited thereon.

[0113] In order to adjust the adhesiveness with the pressure-sensitive adhesive layer or thermosetting protective film-forming film provided thereon, the surface of the substrate may be subjected to roughening treatment such as sandblasting or solvent treatment; oxidation treatment such as corona discharge treatment, electron beam irradiation treatment, plasma treatment, ozone / ultraviolet irradiation treatment, flame treatment, chromic acid treatment, or hot air treatment; lipophilic treatment; hydrophilic treatment; etc. The surface of the substrate may also be treated with a primer.

[0114] The substrate may contain a specific range of components (for example, a resin) to provide adhesiveness on at least one surface.

[0115] Adhesive layer The pressure-sensitive adhesive layer is in the form of a sheet or film and contains a pressure-sensitive adhesive. Examples of the adhesive include adhesive resins such as acrylic resins, urethane resins, rubber-based resins, silicone resins, epoxy-based resins, polyvinyl ethers, polycarbonates, and ester-based resins.

[0116] In this specification, the term "adhesive resin" includes both a resin having adhesive properties and a resin having adhesive properties. For example, the adhesive resin includes not only resins that are adhesive by themselves, but also resins that become adhesive when used in combination with other components such as additives, and resins that become adhesive in the presence of a trigger such as heat or water.

[0117] The adhesive layer may consist of one layer (single layer), or may consist of two or more layers. When it consists of multiple layers, these multiple layers may be the same or different from each other, and the combination of these multiple layers is not particularly limited.

[0118] The thickness of the pressure-sensitive adhesive layer is not particularly limited, but is preferably 1 to 100 μm, more preferably 1 to 60 μm, and particularly preferably 1 to 30 μm. Here, "thickness of the adhesive layer" means the thickness of the entire adhesive layer, and for example, the thickness of an adhesive layer consisting of multiple layers means the total thickness of all layers that make up the adhesive layer.

[0119] The pressure-sensitive adhesive layer is preferably transparent, and may be colored depending on the purpose. When the thermosetting protective film-forming film has energy ray curability, the pressure-sensitive adhesive layer is preferably one that transmits energy rays.

[0120] The pressure-sensitive adhesive layer may be either energy ray-curable or non-energy ray-curable. The physical properties of the energy ray-curable pressure-sensitive adhesive layer can be adjusted before and after curing. For example, by curing the energy ray-curable pressure-sensitive adhesive layer before picking up the protective film-equipped chip described below, the protective film-equipped chip can be more easily picked up.

[0121] The pressure-sensitive adhesive layer can be formed using a pressure-sensitive adhesive composition containing a pressure-sensitive adhesive. For example, the pressure-sensitive adhesive composition can be applied to a surface on which the pressure-sensitive adhesive layer is to be formed, and then dried as necessary to form the pressure-sensitive adhesive layer at the desired location. The ratio of the contents of the components that do not vaporize at room temperature in the pressure-sensitive adhesive composition is usually the same as the ratio of the contents of the components in the pressure-sensitive adhesive layer.

[0122] The application and drying of the pressure-sensitive adhesive composition can be carried out, for example, by the same method as in the application and drying of the pressure-sensitive adhesive composition for a jig described above.

[0123] When the adhesive layer is energy ray-curable, examples of the energy ray-curable adhesive composition include adhesive composition (I-1) containing a non-energy ray-curable adhesive acrylic resin (I-1a) (hereinafter sometimes abbreviated as "adhesive resin (I-1a)") that has a hydroxyl group and is non-energy ray-curable and adhesive, and an energy ray-curable compound; adhesive composition (I-2) containing an energy ray-curable adhesive resin (I-2a) (hereinafter sometimes abbreviated as "adhesive resin (I-2a)") in which an unsaturated group has been introduced into the side chain of the non-energy ray-curable adhesive resin (I-1a); adhesive composition (I-3) containing the adhesive resin (I-2a) and an energy ray-curable compound, and the like.

[0124] When the pressure-sensitive adhesive layer is non-energy ray curable, examples of the non-energy ray curable pressure-sensitive adhesive composition include a pressure-sensitive adhesive composition (I-4) containing the non-energy ray curable pressure-sensitive adhesive resin (I-1a).

[0125] [Non-energy ray curable adhesive resin (I-1a)] The adhesive resin (I-1a) is an acrylic resin having a hydroxyl group. Examples of the acrylic resin include acrylic polymers having structural units derived from hydroxyl group-containing monomers and structural units derived from alkyl (meth)acrylate esters. The (meth)acrylic acid alkyl ester may be, for example, one in which the alkyl group constituting the alkyl ester has 1 to 20 carbon atoms, and the alkyl group is preferably linear or branched.

[0126] The acrylic polymer may further contain, in addition to the structural units derived from hydroxyl group-containing monomers and the structural units derived from alkyl (meth)acrylate esters, structural units derived from functional group-containing monomers other than hydroxyl group-containing monomers. Examples of functional group-containing monomers, including hydroxyl group-containing monomers, include those in which the functional group reacts with a crosslinking agent described below to become a crosslinking starting point, and those in which the functional group reacts with a functional group such as an isocyanate group or a glycidyl group in an unsaturated group-containing compound described below to enable the introduction of an unsaturated group into the side chain of the acrylic polymer.

[0127] Examples of the functional group-containing monomer include hydroxyl group-containing monomers, as well as carboxy group-containing monomers, amino group-containing monomers, and epoxy group-containing monomers.

[0128] The acrylic polymer may further contain structural units derived from other monomers in addition to the structural units derived from the (meth)acrylic acid alkyl ester and the structural units derived from the functional group-containing monomer. The other monomer is not particularly limited as long as it is copolymerizable with the (meth)acrylic acid alkyl ester or the like. Examples of the other monomers include styrene, α-methylstyrene, vinyltoluene, vinyl formate, vinyl acetate, acrylonitrile, and acrylamide.

[0129] In the pressure-sensitive adhesive composition (I-1), pressure-sensitive adhesive composition (I-2), pressure-sensitive adhesive composition (I-3) and pressure-sensitive adhesive composition (I-4) (hereinafter, these pressure-sensitive adhesive compositions are collectively referred to as "pressure-sensitive adhesive compositions (I-1) to (I-4)"), the structural unit contained in the acrylic resin such as the acrylic polymer may be of one type or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0130] In the acrylic polymer, the proportion of the amount of structural units derived from functional group-containing monomers relative to the total amount of structural units is preferably 1 to 35% by mass.

[0131] The adhesive resin (I-1a) contained in the adhesive composition (I-1) or (I-4) may be one type or two or more types, and when two or more types are contained, the combination and ratio thereof can be selected arbitrarily.

[0132] In the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition (I-1) or the pressure-sensitive adhesive composition (I-4), the content of the pressure-sensitive adhesive resin (I-1a) relative to the total mass of the pressure-sensitive adhesive layer is preferably 5 to 99 mass%, and may be, for example, any one of 25 to 98 mass%, 45 to 97 mass%, and 65 to 96 mass%.

[0133] [Energy ray curable adhesive resin (I-2a)] The adhesive resin (I-2a) can be obtained, for example, by reacting a functional group in the adhesive resin (I-1a) with an unsaturated group-containing compound having an energy ray-polymerizable unsaturated group.

[0134] The unsaturated group-containing compound is a compound that, in addition to the energy ray-polymerizable unsaturated group, further has a group that can bond to the adhesive resin (I-1a) by reacting with a functional group in the adhesive resin (I-1a). Examples of the energy ray-polymerizable unsaturated group include a (meth)acryloyl group, a vinyl group (ethenyl group), and an allyl group (2-propenyl group), and the (meth)acryloyl group is preferred. Examples of groups capable of bonding to functional groups in the adhesive resin (I-1a) include isocyanate groups and glycidyl groups capable of bonding to hydroxyl groups or amino groups, and hydroxyl groups and amino groups capable of bonding to carboxyl groups or epoxy groups.

[0135] Examples of the unsaturated group-containing compound include (meth)acryloyloxyethyl isocyanate, (meth)acryloyl isocyanate, and glycidyl (meth)acrylate.

[0136] The adhesive resin (I-2a) contained in the adhesive composition (I-2) or (I-3) may be one type or two or more types, and when two or more types are contained, the combination and ratio thereof can be selected arbitrarily.

[0137] In the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition (I-2) or (I-3), the content of the pressure-sensitive adhesive resin (I-2a) relative to the total mass of the pressure-sensitive adhesive layer is preferably 5 to 99 mass %.

[0138] [Energy ray curable compounds] The energy ray-curable compound contained in the pressure-sensitive adhesive composition (I-1) or (I-3) includes a monomer or oligomer having an energy ray-polymerizable unsaturated group and capable of being cured by irradiation with energy rays.

[0139] Among the energy ray-curable compounds, examples of the monomer include polyvalent (meth)acrylates such as trimethylolpropane tri(meth)acrylate, pentaerythritol (meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butylene glycol di(meth)acrylate, and 1,6-hexanediol (meth)acrylate; urethane (meth)acrylate; polyester (meth)acrylate; polyether (meth)acrylate; and epoxy (meth)acrylate. Among the energy ray-curable compounds, examples of oligomers include oligomers that are polymers of the above-exemplified monomers.

[0140] The pressure-sensitive adhesive composition (I-1) or (I-3) may contain only one type of energy ray-curable compound, or two or more types. When two or more types are contained, the combination and ratio thereof can be selected arbitrarily.

[0141] In the pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition (I-1) or (I-3), the content of the energy ray-curable compound relative to the total mass of the pressure-sensitive adhesive layer is preferably 1 to 95 mass %.

[0142] [Crosslinking agent] The pressure-sensitive adhesive compositions (I-1) to (I-4) further contain an isocyanate-based crosslinking agent.

[0143] The crosslinking agent reacts with the hydroxyl groups to crosslink the adhesive resins (I-1a) together or the adhesive resins (I-2a) together.

[0144] In the pressure-sensitive adhesive compositions (I-1) to (I-4), the content of the crosslinking agent is preferably 0.01 to 50 parts by mass relative to 100 parts by mass of the pressure-sensitive adhesive resin (I-1a) or the pressure-sensitive adhesive resin (I-2a), and may be, for example, any of 1 to 40 parts by mass, 5 to 35 parts by mass, and 10 to 30 parts by mass.

[0145] [Photopolymerization initiator] The pressure-sensitive adhesive compositions (I-1), (I-2) and (I-3) (hereinafter collectively referred to as "pressure-sensitive adhesive compositions (I-1) to (I-3)") may further contain a photopolymerization initiator. The pressure-sensitive adhesive compositions (I-1) to (I-3) containing a photopolymerization initiator undergo a sufficient curing reaction even when irradiated with relatively low-energy energy rays such as ultraviolet light.

[0146] Examples of the photopolymerization initiator 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, α-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 β-chloroanthraquinone.

[0147] The photopolymerization initiators contained in the pressure-sensitive adhesive compositions (I-1) to (I-3) may be one type only, or two or more types. When two or more types are contained, the combination and ratio thereof can be selected arbitrarily.

[0148] In the pressure-sensitive adhesive composition (I-1), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass relative to 100 parts by mass of the content of the energy ray-curable compound. In the pressure-sensitive adhesive composition (I-2), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass per 100 parts by mass of the pressure-sensitive adhesive resin (I-2a). In the pressure-sensitive adhesive composition (I-3), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass relative to 100 parts by mass of the total content of the pressure-sensitive adhesive resin (I-2a) and the energy ray-curable compound.

[0149] [Other additives] The pressure-sensitive adhesive compositions (I-1) to (I-4) may contain other additives that do not fall under any of the above-mentioned components, as long as the effects of the present invention are not impaired. Examples of the other additives include known additives such as antistatic agents, antioxidants, softeners (plasticizers), fillers, rust inhibitors, colorants (pigments, dyes), sensitizers, tackifiers, reaction retarders, and crosslinking accelerators (catalysts). The reaction retarder is a component that inhibits the progress of unintended crosslinking reactions in the pressure-sensitive adhesive compositions (I-1) to (I-4) during storage due to the action of a catalyst mixed in the pressure-sensitive adhesive compositions (I-1) to (I-4). Examples of the reaction retarder include those that form chelate complexes by chelating with the catalyst, and more specifically, those having two or more carbonyl groups (-C(=O)-) in one molecule.

[0150] The other additives contained in the pressure-sensitive adhesive compositions (I-1) to (I-4) may be one type only, or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0151] The content of other additives in the pressure-sensitive adhesive compositions (I-1) to (I-4) is not particularly limited and may be selected appropriately depending on the type of additive.

[0152] [solvent] The pressure-sensitive adhesive compositions (I-1) to (I-4) may contain a solvent, which improves the suitability of the pressure-sensitive adhesive compositions (I-1) to (I-4) for application to a surface to be coated.

[0153] The solvent is preferably an organic solvent, and examples of the organic solvent include ketones such as methyl ethyl ketone and acetone; esters (carboxylic acid esters) such as ethyl acetate; ethers such as tetrahydrofuran and dioxane; aliphatic hydrocarbons such as cyclohexane and n-hexane; aromatic hydrocarbons such as toluene and xylene; and alcohols such as 1-propanol and 2-propanol.

[0154] The pressure-sensitive adhesive compositions (I-1) to (I-4) may contain only one type of solvent, or two or more types, and when two or more types are contained, the combination and ratio thereof can be selected arbitrarily.

[0155] The content of the solvent in the pressure-sensitive adhesive compositions (I-1) to (I-4) is not particularly limited and may be adjusted appropriately.

[0156] Method for producing pressure-sensitive adhesive composition The pressure-sensitive adhesive compositions such as pressure-sensitive adhesive compositions (I-1) to (I-4) can be obtained by blending the pressure-sensitive adhesive and, if necessary, components other than the pressure-sensitive adhesive, for constituting the pressure-sensitive adhesive composition. The order of addition of the components when blending is not particularly limited, and two or more components may be added simultaneously. The method for mixing the components during blending is not particularly limited, and may be appropriately selected from known methods such as a method of mixing by rotating a stirrer or stirring blades, a method of mixing using a mixer, or a method of mixing by adding ultrasound. The temperature and time for adding and mixing each component are not particularly limited as long as the components do not deteriorate, and may be adjusted appropriately. A temperature of 15 to 30°C is preferred.

[0157] Method for manufacturing pressure-sensitive adhesive layer The pressure-sensitive adhesive layer can be formed using a pressure-sensitive adhesive composition containing a pressure-sensitive adhesive. For example, the pressure-sensitive adhesive composition can be applied to a surface on which the pressure-sensitive adhesive layer is to be formed and then dried to form the pressure-sensitive adhesive layer at the desired location. The ratio of the contents of the components that do not vaporize at room temperature in the pressure-sensitive adhesive composition is usually the same as the ratio of the contents of the components in the pressure-sensitive adhesive layer.

[0158] The pressure-sensitive adhesive composition may be applied by a known method, for example, a method using various coaters such as an air knife coater, a blade coater, a bar coater, a gravure coater, a roll coater, a roll knife coater, a curtain coater, a die coater, a knife coater, a screen coater, a Mayer bar coater, or a kiss coater.

[0159] The drying conditions for the pressure-sensitive adhesive composition are not particularly limited. However, when the pressure-sensitive adhesive composition contains a solvent, it is preferable to heat-dry it. And, the pressure-sensitive adhesive composition containing a solvent is preferably heat-dried under conditions of, for example, 70 to 130°C for 10 seconds to 5 minutes.

[0160] ◇Support sheet manufacturing method

[0161] When providing a pressure-sensitive adhesive layer on a substrate, for example, a pressure-sensitive adhesive composition may be applied to the substrate and dried as necessary. Alternatively, for example, a pressure-sensitive adhesive composition may be applied to a release film and dried as necessary to form a pressure-sensitive adhesive layer on the release film, and the exposed surface of this pressure-sensitive adhesive layer may be attached to one surface of the substrate to laminate the pressure-sensitive adhesive layer on the substrate. In this case, the release film may be removed at any time during the production process or use process of the composite sheet for forming a protective film.

[0162] Thermosetting protective film The thermosetting protective film-forming film is used by being attached to the back surface of a workpiece such as a semiconductor wafer in a method for manufacturing a chip with a protective film, and is used to protect the back surface of the workpiece or a chip obtained by dividing the workpiece. In this specification, a protective film-forming film at room temperature is heated to a temperature above room temperature and then cooled to room temperature to obtain a protective film-forming film after heating and cooling, and when the hardness of the resin film-forming film after heating and cooling is compared with the hardness of the resin film-forming film before heating at the same temperature, if the resin film-forming film after heating and cooling is harder, then this protective film-forming film is thermosetting.

[0163] By using the composite sheet for forming a protective film, a chip with a protective film can be manufactured by the method for manufacturing a chip with a protective film described below, which includes a chip and a protective film provided on the back surface of the chip.

[0164] Furthermore, by using the chip with the protective film, a substrate device can be manufactured. In this specification, the term "substrate device" refers to a device in which a chip with a protective film is flip-chip connected to connection pads on a circuit board at protruding electrodes on the circuit surface of the chip. For example, if a semiconductor wafer is used as the wafer, the substrate device may be a semiconductor device.

[0165] The thermosetting protective film-forming film can be formed using a protective film-forming composition (III-1) described below.

[0166] <Protective film forming composition (III-1)> Examples of compositions for forming thermosetting protective films include a composition (III-1) for forming thermosetting protective films (sometimes abbreviated herein as "composition (III-1) for forming protective films") containing a polymer component (A) and a thermosetting component (B).

[0167] [Polymer component (A)] The polymer component (A) is a polymer compound that imparts film-forming properties, flexibility, and the like to the thermosetting protective film-forming film. The polymer component (A) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one type or two or more types, and if there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0168] Examples of the polymer component (A) include thermoplastic acrylic resins, thermoplastic polyester resins (thermoplastic resins having ester bonds), thermoplastic polyurethane resins (thermoplastic resins having urethane bonds), thermoplastic acrylic urethane resins, thermoplastic silicone resins (thermoplastic resins having siloxane bonds), thermoplastic rubber resins (thermoplastic resins having a rubber structure), thermoplastic phenoxy resins, and thermoplastic polyimides (thermoplastic resins having imide bonds), with thermoplastic acrylic resins being preferred.

[0169] The acrylic resin is a resin containing structural units derived from (meth)acrylic acid ester monomers. Here, "derived from" means that the monomers have undergone the structural changes necessary for polymerization. In this specification, the term "(meth)acrylic acid" is a concept that encompasses both "acrylic acid" and "methacrylic acid." The same applies to terms similar to (meth)acrylic acid.

[0170] The acrylic resin in the polymer component (A) may be any known acrylic polymer. The weight-average molecular weight (Mw) of the acrylic resin is preferably 10,000 to 2,000,000, and more preferably 100,000 to 1,500,000. 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 thermosetting protective film-forming film is improved. Furthermore, when the weight-average molecular weight of the acrylic resin is equal to or less than the upper limit, the thermosetting protective film-forming film can more easily conform to the uneven surface of the adherend, and the occurrence of voids and the like between the adherend and the thermosetting protective film-forming film is further suppressed.

[0171] The glass transition temperature (Tg) of the acrylic resin is preferably −60 to 70° C., more preferably −30 to 50° C. When the Tg of the acrylic resin is equal to or higher than the lower limit, the adhesive strength between the protective film and the support sheet is suppressed, improving the peelability of the support sheet. Furthermore, when the Tg of the acrylic resin is equal to or lower than the upper limit, the adhesive strength between the thermosetting protective film-forming film and the protective film and the adherend is improved.

[0172] 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 esters, (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N-methylolacrylamide.

[0173] 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 p) (meth)acrylic acid alkyl esters in which the alkyl group constituting the alkyl ester has a chain structure and has 1 to 18 carbon atoms, such as isononyl acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauryl (meth)acrylate), tridecyl (meth)acrylate, tetradecyl (meth)acrylate (myristyl (meth)acrylate), pentadecyl (meth)acrylate, hexadecyl (meth)acrylate (palmityl (meth)acrylate), heptadecyl (meth)acrylate, and octadecyl (meth)acrylate (stearyl (meth)acrylate); (meth)acrylic acid cycloalkyl esters such as isobornyl (meth)acrylate and dicyclopentanyl (meth)acrylate; (Meth)acrylic acid aralkyl esters such as benzyl (meth)acrylate; (Meth)acrylic acid cycloalkenyl esters such as (meth)acrylic acid dicyclopentenyl ester; (Meth)acrylic acid cycloalkenyloxyalkyl esters such as (meth)acrylic acid dicyclopentenyloxyethyl ester; (Meth)acrylic acid imide; glycidyl group-containing (meth)acrylic acid esters such as glycidyl (meth)acrylate; hydroxyl group-containing (meth)acrylic acid esters such as hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; Examples include substituted amino group-containing (meth)acrylic acid esters such as N-methylaminoethyl (meth)acrylate. Here, the term "substituted amino group" refers to a group in which one or two hydrogen atoms of an amino group are substituted with a group other than a hydrogen atom.

[0174] The acrylic resin may be obtained by copolymerizing, in addition to the (meth)acrylic acid ester, one or more monomers selected from (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, N-methylolacrylamide, and the like.

[0175] The acrylic resin may be made up of one kind of monomer or two or more kinds of monomers, and when two or more kinds of monomers are used, the combination and ratio thereof can be selected arbitrarily.

[0176] The acrylic resin may have a functional group capable of bonding to 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 bond to other compounds via a crosslinking agent (F) described below, or may bond directly to other compounds without the crosslinking agent (F). Bonding of the acrylic resin to other compounds via the functional group tends to improve the reliability of a package obtained using the composite sheet for forming a protective film.

[0177] In this specification, as the polymer component (A), a thermoplastic resin other than an acrylic resin (hereinafter sometimes simply abbreviated as a "thermoplastic resin") may be used in combination with an acrylic resin. By using the thermoplastic resin, the peelability of the protective film from the support sheet can be improved, the thermosetting protective film-forming film can more easily conform to the uneven surface of the substrate, and the occurrence of voids, etc. between the substrate and the thermosetting protective film-forming film can be more effectively suppressed.

[0178] The weight average molecular weight of the thermoplastic resin is preferably 1,000 to 100,000, and more preferably 3,000 to 80,000.

[0179] The glass transition temperature (Tg) of the thermoplastic resin is preferably from -30 to 150°C, more preferably from -20 to 120°C.

[0180] Examples of the thermoplastic resin include polyester resin, polyurethane resin, phenoxy resin, polybutene, polybutadiene, and polystyrene.

[0181] The thermoplastic resin contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one type or two or more types, and if there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0182] In the protective film-forming composition (III-1), the ratio of the content of polymer component (A) to the total content of all components other than the solvent (i.e., the ratio of the content of polymer component (A) in the thermosetting protective film-forming film to the total mass of the thermosetting protective film-forming film) is, regardless of the type of polymer component (A), preferably 1 mass% or more and less than 85 mass%, preferably 2 mass% or more and less than 65 mass%, more preferably 3 mass% or more and less than 50 mass%, even more preferably 4 mass% or more and less than 40 mass%, particularly preferably 5 mass% or more and less than 35 mass%, and particularly preferably 10 mass% or more and less than 30 mass%.

[0183] The polymer component (A) may also correspond to the thermosetting component (B). In this specification, when the protective film-forming composition (III-1) contains components that correspond to both the polymer component (A) and the thermosetting component (B), the protective film-forming composition (III-1) is considered to contain the polymer component (A) and the thermosetting component (B).

[0184] [Thermosetting component (B)] The thermosetting component (B) has thermosetting properties and is a component for curing the thermosetting protective film-forming film to form a hard protective film. The thermosetting component (B) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one type or two or more types, and if there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0185] Examples of the thermosetting component (B) include epoxy thermosetting resins (thermosetting resins having epoxy groups), thermosetting polyimides (thermosetting resins having imide bonds), thermosetting polyurethane resins (thermosetting resins having urethane bonds), thermosetting unsaturated polyester resins (thermosetting resins having ester bonds and unsaturated bonds between carbon atoms), and thermosetting silicone resins (thermosetting resins having siloxane bonds), with epoxy thermosetting resins being preferred.

[0186] (epoxy thermosetting resin) The epoxy thermosetting resin is composed of an epoxy resin (B1) and a thermosetting agent (B2). The epoxy-based thermosetting resin contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one type or two or more types, and if there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0187] Epoxy resin (B1) The epoxy resin (B1) may be one having an epoxy group in the molecule, and examples thereof include known epoxy resins, such as polyfunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ether and its hydrogenated products, orthocresol novolac epoxy resins, dicyclopentadiene-type epoxy resins, biphenyl-type epoxy resins, bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, and phenylene skeleton-type epoxy resins, as well as bifunctional or higher epoxy compounds having two or more epoxy groups in the molecule.

[0188] As the epoxy resin (B1), an epoxy resin having an unsaturated hydrocarbon group may be used. Epoxy resins having an unsaturated hydrocarbon group have higher compatibility with acrylic resins than epoxy resins not having an unsaturated hydrocarbon group. Therefore, by using an epoxy resin having an unsaturated hydrocarbon group, the reliability of the package obtained using the composite sheet for forming a protective film is improved.

[0189] Examples of epoxy resins having unsaturated hydrocarbon groups include compounds obtained by converting some of the epoxy groups of a polyfunctional epoxy resin into groups having unsaturated hydrocarbon groups. Such compounds can be obtained, for example, by subjecting epoxy groups to an addition reaction with (meth)acrylic acid or a derivative thereof. Furthermore, examples of epoxy resins having an unsaturated hydrocarbon group include compounds in which a group having an unsaturated hydrocarbon group is directly bonded to an aromatic ring or the like constituting the epoxy resin. The unsaturated hydrocarbon group is a polymerizable unsaturated group, and specific examples thereof include an ethenyl group (vinyl group), a 2-propenyl group (allyl group), a (meth)acryloyl group, and a (meth)acrylamide group, with an acryloyl group being preferred. In this specification, the term "derivative" refers to a compound in which one or more hydrogen atoms of the original compound have been substituted with a group (substituent) other than a hydrogen atom.

[0190] The number average molecular weight of the epoxy resin (B1) is not particularly limited, but from the viewpoints of the curability of the thermosetting protective film-forming film and the strength and heat resistance of the protective film after curing, it is preferably 300 to 30,000, more preferably 300 to 10,000, and particularly preferably 300 to 3,000. The epoxy equivalent of the epoxy resin (B1) is preferably 100 to 1100 g / eq, more preferably 150 to 1000 g / eq.

[0191] The epoxy resin (B1) may be used alone or in combination of two or more kinds. When two or more kinds are used in combination, the combination and ratio thereof can be selected arbitrarily.

[0192] Heat hardener (B2) The heat curing agent (B2) functions as a curing agent for the epoxy resin (B1). The thermosetting agent (B2) may be, for example, a compound having two or more functional groups per molecule that can react with an epoxy group. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group, and an anhydride group of an acid group. A phenolic hydroxyl group, an amino group, or an anhydride group of an acid group is preferred, and a phenolic hydroxyl group or an amino group is more preferred.

[0193] Among the heat curing agents (B2), examples of phenolic curing agents having a phenolic hydroxyl group include polyfunctional phenolic resins, biphenols, novolac-type phenolic resins, dicyclopentadiene-based phenolic resins, and aralkyl phenolic resins. Among the heat curing agents (B2), examples of amine-based curing agents having an amino group include dicyandiamide (hereinafter sometimes abbreviated as "DICY").

[0194] The heat curing agent (B2) may have an unsaturated hydrocarbon group. Examples of the thermosetting agent (B2) having an unsaturated hydrocarbon group include a compound in which some of the hydroxyl groups of a phenolic resin are substituted with a group having an unsaturated hydrocarbon group, and a compound in which a group having an unsaturated hydrocarbon group is directly bonded to an aromatic ring of a phenolic resin. The unsaturated hydrocarbon group in the heat curing agent (B2) is the same as the unsaturated hydrocarbon group in the epoxy resin having an unsaturated hydrocarbon group described above.

[0195] 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, since this improves the peelability of the protective film from the support sheet.

[0196] The thermosetting agent (B2) is preferably a thermosetting agent that is solid at room temperature and does not exhibit curing activity toward the epoxy resin (B1), but melts upon heating and exhibits curing activity toward the epoxy resin (B1) (hereinafter, this may be abbreviated as "thermally active latent epoxy resin curing agent"). The heat-activated latent epoxy resin curing agent is stably dispersed in the epoxy resin (B1) in the thermosetting protective film-forming film at room temperature, but becomes compatible with the epoxy resin (B1) and reacts with the epoxy resin (B1) upon heating. The use of the heat-activated latent epoxy resin curing agent significantly improves the storage stability of the protective film-forming composite sheet. For example, migration of the curing agent from the thermosetting protective film-forming film to the adjacent support sheet is suppressed, effectively suppressing a decrease in the thermosetting ability of the thermosetting protective film-forming film. Furthermore, the thermosetting ability of the thermosetting protective film-forming film upon heating is enhanced, thereby further improving the pick-up ability of the protective film-attached chip, as described below.

[0197] Examples of the heat-activatable latent epoxy resin curing agent include onium salts, dibasic acid hydrazides, dicyandiamide, and amine adducts of curing agents.

[0198] 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 particularly preferably 500 to 3,000. Of the thermosetting agent (B2), the molecular weight of the non-resin component such as biphenol or dicyandiamide is not particularly limited, but is preferably 60 to 500, for example.

[0199] The heat curing agent (B2) may be used alone or in combination of two or more kinds. When two or more kinds are used in combination, the combination and ratio thereof can be selected arbitrarily.

[0200] In the protective film-forming composition (III-1) and the thermosetting protective film-forming film, the content of the thermosetting curing agent (B2) is preferably 0.1 to 500 parts by mass, and more preferably 1 to 200 parts by mass, per 100 parts by mass of the epoxy resin (B1). When the content of the thermosetting curing agent (B2) is equal to or greater than the lower limit, curing of the thermosetting protective film-forming film proceeds more easily. Furthermore, when the content of the thermosetting curing agent (B2) is equal to or less than the upper limit, the moisture absorption rate of the thermosetting protective film-forming film is reduced, and the reliability of the package obtained using the composite sheet for forming a protective film is further improved.

[0201] In the protective film-forming composition (III-1), the ratio of the content of the thermosetting component (B) to the total content of all components other than the solvent (i.e., the ratio of the content of the thermosetting component (B) in the thermosetting protective film-forming film to the total mass of the thermosetting protective film-forming film) is, regardless of the type of thermosetting component (B), preferably 1 mass% or more and less than 75 mass%, preferably 2 mass% or more and less than 60 mass%, more preferably 3 mass% or more and less than 50 mass%, even more preferably 4 mass% or more and less than 40 mass%, particularly preferably 5 mass% or more and less than 35 mass%, and particularly preferably 6 mass% or more and less than 30 mass%.

[0202] The thermosetting protective film-forming film of the embodiment contains a polymer component (A) and a thermosetting component (B), and an example thereof is one in which the polymer component (A) is an acrylic resin and the thermosetting component (B) is an epoxy-based thermosetting resin composed of an epoxy resin (B1) and a thermosetting agent (B2).

[0203] [Curing accelerator (C)] The protective film-forming composition (III-1) and the thermosetting protective film-forming film may contain a curing accelerator (C). The curing accelerator (C) is a component for adjusting the curing rate of the protective film-forming composition (III-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.

[0204] The curing accelerator (C) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one type or two or more types, and if there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0205] When the curing accelerator (C) is used, the content of the curing accelerator (C) in the protective film-forming composition (III-1) and the thermosetting protective film-forming film is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the thermosetting component (B). When the content of the curing accelerator (C) is equal to or greater than the lower limit, the effect of using the curing accelerator (C) is more pronounced. Furthermore, when the content of the curing accelerator (C) is equal to or less than the upper limit, for example, the effect of suppressing the highly polar curing accelerator (C) from migrating to the adhesive interface with the adherend and segregating in the thermosetting protective film-forming film under high temperature and high humidity conditions is enhanced, thereby further improving the reliability of the package obtained using the composite sheet for forming a protective film.

[0206] [Filling material (D)] The protective film-forming composition (III-1) and the thermosetting protective film-forming film may contain a filler (D). When the thermosetting protective film-forming film contains the filler (D), the thermal expansion coefficient of the protective film obtained by curing the thermosetting protective film-forming film can be easily adjusted, and by optimizing this thermal expansion coefficient for the object on which the protective film is formed, the reliability of the package obtained using the composite sheet for protective film formation is further improved. Furthermore, when the thermosetting protective film-forming film contains the filler (D), the moisture absorption rate of the protective film can be reduced and heat dissipation properties can be improved.

[0207] 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 spheronizing these inorganic fillers; surface-modified products of these inorganic fillers; single-crystal fibers of these inorganic fillers; glass fibers, etc. Among these, the inorganic filler is preferably silica or alumina.

[0208] The filler (D) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one type or two or more types, and if there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0209] When using filler (D), in the protective film-forming composition (III-1), the content ratio of filler (D) to the total content of all components other than the solvent (i.e., the content ratio of filler (D) to the total mass of the thermosetting protective film-forming film in the thermosetting protective film-forming film) is preferably greater than 5% by mass and less than 85% by mass, more preferably greater than 20% by mass and less than 85% by mass, more preferably greater than 30% by mass and less than 80% by mass, even more preferably greater than 45% by mass and less than 80% by mass, and particularly preferably greater than 46% by mass and less than 75% by mass. When the content of filler (D) is in such a range, it becomes easier to adjust the thermal expansion coefficient.

[0210] [Coupling agent (E)] The protective film-forming composition (III-1) and the thermosetting protective film-forming film 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 thermosetting protective film-forming film to an adherend can be improved. Furthermore, by using the coupling agent (E), the protective film obtained by curing the thermosetting protective film-forming film has improved water resistance without impairing heat resistance.

[0211] The coupling agent (E) is preferably a compound having a functional group capable of reacting with the functional group of the polymer component (A), the thermosetting component (B), etc., and is more preferably a silane coupling agent. Preferred examples of the silane coupling agent include 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxymethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-(2-aminoethylamino)propyltrimethoxysilane, 3-(2- Examples of such silanes include (aminoethylamino)propylmethyldiethoxysilane, 3-(phenylamino)propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, bis(3-triethoxysilylpropyl)tetrasulfane, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, and imidazole silane.

[0212] The coupling agent (E) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one type or two or more types, and if there are two or more types, their combination and ratio can be selected arbitrarily.

[0213] When a coupling agent (E) is used, the content of the coupling agent (E) in the protective film-forming composition (III-1) and the thermosetting protective film-forming film is preferably 0.03 to 20 parts by mass, more preferably 0.05 to 10 parts by mass, and particularly 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 at or above the lower limit, the effects of using the coupling agent (E), such as improved dispersibility of the filler (D) in the resin and improved adhesion of the thermosetting protective film-forming film to the substrate, are more significantly obtained. Furthermore, when the content of the coupling agent (E) is at or below the upper limit, the generation of outgassing is further suppressed.

[0214] [Crosslinker (F)] When the polymer component (A) is a polymer having a functional group such as a vinyl group, (meth)acryloyl group, amino group, hydroxyl group, carboxyl group, or isocyanate group that can bond with other compounds, such as the acrylic resin described above, the protective film-forming composition (III-1) and the thermosetting protective film-forming film may contain a crosslinking agent (F) for bonding the functional group with other compounds to form crosslinks. By crosslinking using the crosslinking agent (F), the storage modulus E' of the thermosetting protective film-forming film can be easily adjusted to a suitable range.

[0215] An example of such a configuration is a thermosetting protective film-forming film containing a polymer component (A) having a structural unit containing a functional group (a1) and a crosslinking agent (F) having two or more functional groups (f1) that react with the functional group (a1).

[0216] The content of the structural unit containing the functional group (a1) relative to 100 parts by mass of the polymer component (A) is preferably 3 parts by mass or more, more preferably 3 parts by mass or more and 40 parts by mass or less, even more preferably 5 parts by mass or more and 30 parts by mass or less, and particularly preferably 7 parts by mass or more and 20 parts by mass or less. When the content of the structural unit containing the functional group (a1) is within the above range, the storage modulus E' of the thermosetting protective film-forming film can be easily adjusted to a suitable range.

[0217] Furthermore, the content of the functional group (f1) relative to 1 equivalent of the functional group (a1) is preferably 0.005 to 4 equivalents, more preferably 0.05 to 2 equivalents, and even more preferably 0.1 to 1 equivalent. When the content of the functional group (f1) is within the above range, the storage modulus E' of the thermosetting protective film-forming film can be easily adjusted to a suitable range.

[0218] 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).

[0219] Examples of the organic polyisocyanate compound include aromatic polyisocyanate compounds, aliphatic polyisocyanate compounds, and alicyclic polyisocyanate compounds (hereinafter, these compounds may be collectively referred to as "aromatic polyisocyanate compounds, etc."); trimers, isocyanurates, and adducts of the aromatic polyisocyanate compounds, etc.; and isocyanate-terminated urethane prepolymers obtained by reacting the aromatic polyisocyanate compounds, etc. with polyol compounds. The "adducts" refer to reaction products of the aromatic polyisocyanate compounds, aliphatic polyisocyanate compounds, or alicyclic polyisocyanate compounds with low-molecular-weight active hydrogen-containing compounds such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, or castor oil. Examples include the xylylene diisocyanate adduct of trimethylolpropane, as described below. The term "isocyanate-terminated urethane prepolymer" is as described above.

[0220] Examples of the organic polyisocyanate compound include isocyanate-based crosslinking agents (i.e., crosslinking agents having two or more isocyanate groups) such as tolylene diisocyanate (TDI)-based, hexamethylene diisocyanate (HDI)-based, xylylene diisocyanate (XDI)-based, and adducts of these diisocyanates.

[0221] More specific examples of the organic polyisocyanate compound include 2,4-tolylene diisocyanate; 2,6-tolylene diisocyanate; 1,3-xylylene diisocyanate; 1,4-xylylene diisocyanate; diphenylmethane-4,4'-diisocyanate; diphenylmethane-2,4'-diisocyanate; 3-methyldiphenylmethane diisocyanate; hexamethylene diisocyanate; isophorone diisocyanate; dicyclohexylmethane-4,4'-diisocyanate; dicyclohexylmethane-2,4'-diisocyanate; a compound in which one or more of tolylene diisocyanate, hexamethylene diisocyanate, and xylylene diisocyanate are added to all or some of the hydroxyl groups of a polyol such as trimethylolpropane; lysine diisocyanate, and the like. The number of isocyanate groups per molecule of the organic polyvalent isocyanate compound is preferably 2 to 3.

[0222] 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.

[0223] 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 thermosetting protective film-forming film by the reaction between the crosslinking agent (F) and the polymer component (A).

[0224] An example of such a configuration is a thermosetting protective film-forming film in which the functional group (f1) is an isocyanate group and the functional group (a1) is a hydroxyl group. Examples of the crosslinking agent (F) having two or more isocyanate groups in the molecule include isocyanate-based crosslinking agents, such as the organic polyisocyanate compounds described above. Aromatic polyisocyanate compounds such as XDI-based and TDI-based compounds are preferred in terms of stability when used in a protective film-forming composition and reactivity when used in a thermosetting protective film-forming film. The hydroxyl group-containing structural unit is derived from a hydroxyl group-containing monomer having a hydroxyl group in the molecule. Examples of the hydroxyl group-containing monomer include the hydroxyl group-containing (meth)acrylic acid ester in the polymer component (A), with hydroxyalkyl (meth)acrylate being preferred.

[0225] The crosslinking agent (F) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one type or two or more types, and if there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0226] When a crosslinking agent (F) is used, the content of the crosslinking agent (F) in the protective film-forming composition (III-1) is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 10 parts by mass, and particularly 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 greater than the lower limit, the effect of using the crosslinking agent (F) is more pronounced. Furthermore, when the content of the crosslinking agent (F) is equal to or less than the upper limit, excessive deterioration in the adhesive strength of the thermosetting protective film-forming film to a support sheet and the adhesive strength of the thermosetting protective film-forming film to a wafer or chip is suppressed.

[0227] [Energy ray curable resin (G)] The protective film-forming composition (III-1) may contain an energy ray-curable resin (G). By containing the energy ray-curable resin (G), the thermosetting protective film-forming film can change its properties by irradiation with energy rays.

[0228] The energy ray curable resin (G) is obtained by polymerizing (curing) an energy ray curable compound. Examples of the energy ray-curable compound include compounds having at least one polymerizable double bond in the molecule, and acrylate compounds having a (meth)acryloyl group are preferred.

[0229] Examples of the acrylate compounds include 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. (meth)acrylates containing a cyclic aliphatic skeleton; (meth)acrylates containing a cyclic aliphatic skeleton such as dicyclopentanyl di(meth)acrylate; polyalkylene glycol (meth)acrylates such as polyethylene glycol di(meth)acrylate; oligoester (meth)acrylates; urethane (meth)acrylate oligomers; epoxy-modified (meth)acrylates; polyether (meth)acrylates other than the above-mentioned polyalkylene glycol (meth)acrylates; and itaconic acid oligomers.

[0230] The weight average molecular weight of the energy ray-curable compound is preferably 100 to 30,000, and more preferably 300 to 10,000.

[0231] The energy ray-curable compound used in the polymerization may be one kind or two or more kinds, and when two or more kinds are used, the combination and ratio thereof can be selected arbitrarily.

[0232] The energy ray-curable resin (G) contained in the protective film-forming composition (III-1) may be one type or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0233] In the protective film-forming composition (III-1), the content of the energy ray-curable resin (G) relative to the total mass of the protective film-forming composition (III-1) is preferably 1 to 95 mass%, more preferably 2 to 90 mass%, and particularly preferably 3 to 85 mass%.

[0234] [Photopolymerization initiator (H)] When the protective film-forming composition (III-1) contains an energy ray-curable resin (G), it may contain a photopolymerization initiator (H) to efficiently promote the polymerization reaction of the energy ray-curable resin (G).

[0235] Examples of the photopolymerization initiator (H) in the protective film-forming composition (III-1) include the same photopolymerization initiators as those in the pressure-sensitive adhesive composition (I-1).

[0236] The photopolymerization initiator (H) contained in the composition for forming a protective film (III-1) may be one type or two or more types, and when there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0237] In the protective film-forming composition (III-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 particularly preferably 2 to 5 parts by mass, per 100 parts by mass of the energy ray-curable resin (G).

[0238] [Colorant (I)] The protective film-forming composition (III-1) and the thermosetting protective film-forming film may contain a colorant (I). Examples of the colorant (I) include known colorants such as inorganic pigments, organic pigments, and organic dyes.

[0239] Examples of the organic pigments and organic dyes include aminium-based dyes, cyanine-based dyes, merocyanine-based dyes, croconium-based dyes, squarium-based dyes, azulenium-based dyes, polymethine-based dyes, naphthoquinone-based dyes, pyrylium-based dyes, phthalocyanine-based dyes, naphthalocyanine-based dyes, naphtholactam-based dyes, azo-based dyes, condensed azo-based dyes, indigo-based dyes, perinone-based dyes, perylene-based dyes, dioxazine-based dyes, quinacridone-based dyes, isoindolinone-based dyes, quinophthalone-based dyes, pyrrole-based dyes, thioindigo-based dyes, metal complex-based dyes (metal complex dyes), dithiol metal complex-based dyes, indolephenol-based dyes, triallylmethane-based dyes, anthraquinone-based dyes, dioxazine-based dyes, naphthol-based dyes, azomethine-based dyes, benzimidazolone-based dyes, pyranthrone-based dyes, and threne-based dyes.

[0240] 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.

[0241] The colorant (I) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one type or two or more types, and if there are two or more types, their combination and ratio can be selected arbitrarily.

[0242] When a colorant (I) is used, the content of the colorant (I) in the thermosetting protective film-forming film may be adjusted appropriately depending on the purpose. For example, the protective film may be printed by laser irradiation. The visibility of the printed text can be adjusted by adjusting the content of the colorant (I) in the thermosetting protective film-forming film and adjusting the light transmittance of the protective film. Furthermore, adjusting the content of the colorant (I) in the thermosetting protective film-forming film can improve the design of the protective film or make grinding marks on the backside of the wafer less visible. Taking this into consideration, the ratio of the content of the colorant (I) to the total content of all components other than the solvent in the protective film-forming composition (III-1) (i.e., the ratio of the content of the colorant (I) to the total mass of the thermosetting protective film-forming film) is preferably 0.1 to 10% by mass, more preferably 0.1 to 7.5% by mass, and particularly preferably 0.1 to 5% by mass. When the content of the colorant (I) is equal to or greater than the lower limit, the effect of using the colorant (I) is more pronounced. When the content of the colorant (I) is equal to or less than the upper limit, an excessive decrease in the light transmittance of the thermosetting protective film-forming film is suppressed.

[0243] [General Purpose Additives (J)] The protective film-forming composition (III-1) and the thermosetting protective film-forming film may contain a general-purpose additive (J) within the range that does not impair the effects of the present invention. The general-purpose additive (J) may be a known one and can be selected arbitrarily depending on the purpose, and is not particularly limited. Preferred examples include plasticizers, antistatic agents, antioxidants, gettering agents, etc.

[0244] The general-purpose additive (I) contained in the protective film-forming composition (III-1) and the thermosetting protective film-forming film may be one type or two or more types, and if there are two or more types, the combination and ratio thereof can be selected arbitrarily. The content of the protective film-forming composition (III-1) and the general-purpose additive (I) in the thermosetting protective film-forming film is not particularly limited and may be appropriately selected depending on the purpose.

[0245] [solvent] The composition for forming a protective film (III-1) preferably further contains a solvent. The composition for forming a protective film (III-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 and butyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; and amides (compounds having an amide bond) such as dimethylformamide and N-methylpyrrolidone. The composition for forming a protective film (III-1) may contain one kind of solvent or two or more kinds of solvents, and when two or more kinds of solvents are contained, the combination and ratio thereof can be selected arbitrarily.

[0246] The solvent contained in the composition for forming a protective film (III-1) is preferably methyl ethyl ketone or the like, since this allows the components contained in the composition for forming a protective film (III-1) to be mixed more uniformly.

[0247] Method for producing a thermosetting protective film-forming composition A composition for forming a protective film such as the composition for forming a protective film (III-1) can be obtained by blending the components that constitute the composition. The order of addition of the components when blending is not particularly limited, and two or more components may be added simultaneously. When a solvent is used, the solvent may be mixed with any of the ingredients other than the solvent to pre-dilute the ingredients, or the solvent may be mixed with any of the ingredients other than the solvent without pre-diluting these ingredients. The method for mixing the components during blending is not particularly limited, and may be appropriately selected from known methods such as a method of mixing by rotating a stirrer or stirring blades, a method of mixing using a mixer, or a method of mixing by adding ultrasound. The temperature and time for adding and mixing each component may be adjusted appropriately taking into consideration the conditions under which each compounded component is unlikely to deteriorate, but the temperature is preferably 15 to 30°C. The thermosetting protective film-forming composition can be produced by the same method as the pressure-sensitive adhesive composition described above, except that the types of ingredients used are different.

[0248] ○Adhesive layer for jigs The adhesive layer 16 for a jig is used to fix the composite sheet 101 for forming a protective film to a fixing jig 18 such as a ring frame. The adhesive layer for jig 16 is formed using the adhesive sheet for fixing a jig according to the embodiment of the present invention described above, and is configured by laminating a first adhesive layer 161, a core film 162, and a second adhesive layer 163 in this order in the thickness direction.

[0249] The pressure-sensitive adhesive layer 16 for the jig is preferably ring-shaped.

[0250] The thickness of the pressure-sensitive adhesive layer for a jig is preferably 25 to 70 μm, more preferably 30 to 65 μm, and even more preferably 35 to 60 μm. By having the thickness equal to or greater than the lower limit, the adhesiveness to the fixing jig 18 such as a ring frame can be appropriately adjusted, and by having the thickness equal to or less than the upper limit, the occurrence of wrinkles in the composite sheet for forming a protective film can be prevented.

[0251] Method for manufacturing adhesive layer for jig The jig adhesive layer 16, which consists of a ring-shaped first adhesive layer 161, a core film 162, and a second adhesive layer 163, can be produced, for example, as follows using the jig fixing adhesive sheet shown in Figure 1.

[0252] First release film 151, which serves as a light-surface release film, is peeled off and removed from the jig fixing adhesive sheet shown in Fig. 1. Next, a circular punching blade is applied from the side of first adhesive layer 161 to cut the inner peripheral edges of first adhesive layer 161, core film 162, and second adhesive layer 163, removing the inner circular portions. Next, a circular punching blade is applied concentrically from the side of first adhesive layer 161 to cut the outer peripheral edges of first adhesive layer 161, core film 162, and second adhesive layer 163, removing the outer portions. This allows the production of a jig adhesive layer 16, which is constructed by laminating a ring-shaped second adhesive layer 163, a core film 162, and a first adhesive layer 161 in this order on the second release film 152.

[0253] The composite sheet for forming a protective film of this embodiment can be suitably used in the method for producing a chip with a protective film, which will be described later.

[0254] ◇Manufacturing method of composite sheet for forming protective film The composite sheet for forming a protective film can be produced by laminating the above-mentioned layers in a corresponding positional relationship and adjusting the shapes of some or all of the layers as necessary. The method for forming each layer is as described above.

[0255] It is possible to directly form a thermosetting protective film-forming film by further applying a protective film-forming composition onto the pressure-sensitive adhesive layer already laminated on the substrate. In this way, when a new layer (hereinafter abbreviated as "second layer") is formed on any layer (hereinafter abbreviated as "first layer") already laminated on the substrate to form a continuous two-layer laminate structure (in other words, a laminate structure of the first layer and the second layer), a method can be applied in which a composition for forming the second layer is applied onto the first layer and dried as necessary. However, it is preferable to form the second layer in advance on a release film using a composition for forming the second layer, and then bond the exposed surface of the second layer opposite to the side in contact with the release film to the exposed surface of the first layer to form a continuous two-layer laminate structure. In this case, it is preferable to coat the composition on the release-treated surface of the release film. The release film can be removed as needed after the laminate structure is formed.

[0256] For example, the composite sheet 101 for forming a protective film shown in FIG. 2 can be produced by the following procedure. A support sheet 10 having an adhesive layer 12 already laminated on a substrate 11, and a thermosetting protective film-forming film 13 on a release film are prepared, and the adhesive layer 12 of the support sheet 10 and the thermosetting protective film-forming film 13 are bonded together to prepare a third laminate having the support sheet 10 consisting of the substrate 11 and the adhesive layer 12, the thermosetting protective film-forming film 13, and the release film. The release film is removed from the third laminate. In accordance with the manufacturing method of the adhesive layer for a jig described above, an adhesive layer for a jig 16 is produced by laminating a ring-shaped second adhesive layer 163, a core film 162 and a first adhesive layer 161 in this order on a second release film 152, and the adhesive layer for a jig 16 is bonded to the thermosetting protective film-forming film 13 of the third laminate from which the release film has been removed.

[0257] The composite sheet 101 for forming a protective film shown in FIG. 2 can also be produced by the following procedure. A third laminate is prepared, which includes a support sheet 10 made of a substrate 11 and a pressure-sensitive adhesive layer 12, a thermosetting protective film-forming film 13, and a release film. The second release film 152 is peeled off and removed from the jig fixation adhesive sheet 1 shown in Fig. 1. Next, a circular punching blade is applied from the side of the second adhesive layer 163 to cut the inner peripheral edges of the first adhesive layer 161, core film 162, and second adhesive layer 163, leaving the first release film 151, and the inner circular portions are removed to produce a fourth laminate in which the first adhesive layer 161, core film 162, and second adhesive layer 163, from which the inner circular portions have been removed, are laminated in this order on the first release film 151.

[0258] The release film is peeled off from the third laminate, and the exposed thermosetting protective film-forming film 13 is bonded to the fourth laminate from which the inner circular portion has been removed and the exposed second pressure-sensitive adhesive layer 163. Thereafter, a circular punching blade is applied from the side of the base material 11 to the outside in a concentric circle with the inner circle to cut the outer periphery of the support sheet 10 consisting of the base material 11 and the pressure-sensitive adhesive layer 12, the thermosetting protective film-forming film 13, the second pressure-sensitive adhesive layer 163, the core film 162, and the first pressure-sensitive adhesive layer 161, leaving the first release film 151, and removing the outer portion.

[0259] Here, an example is given in which a thermosetting protective film-forming film is laminated on an adhesive layer, and a ring-shaped adhesive layer for a jig is laminated on the thermosetting protective film-forming film, but the target laminate structure can be selected arbitrarily, for example, when a thermosetting protective film-forming film and an adhesive layer for a jig are laminated on an adhesive layer.

[0260] In this way, all layers other than the substrate that make up the composite sheet for forming a protective film can be formed in advance on a release film and then laminated by laminating it to the surface of the desired layer, so the composite sheet for forming a protective film can be manufactured by appropriately selecting the layers that will undergo this process as needed.

[0261] The composite sheet for forming a protective film may be in the form of a sheet, or preferably in the form of a roll.

[0262] The thermosetting protective film-forming film 13 can be formed using the above-mentioned protective film-forming composition.

[0263] The first release film 151 and the second release film 152 may both be known films. The first release film 151 and the second release film 152 may be the same as each other, or may be different from each other, for example, having different peeling forces required when peeling them from the thermosetting protective film-forming film 13.

[0264] <<Manufacturing method for chips with protective film>> The composite sheet for forming a protective film according to the embodiment of the present invention described above can be used in a method for manufacturing a chip with a protective film, which includes a chip and a protective film provided on the back surface of the chip.

[0265] The method for manufacturing a chip with a protective film according to this embodiment includes the steps of: A process for producing a first laminated composite sheet in which the thermosetting protective film-forming film and the work are laminated in this order in the thickness direction on the support sheet by attaching the jig adhesive layer in the composite sheet for forming a protective film to a fixing jig and attaching the thermosetting protective film-forming film in the composite sheet for forming a protective film according to the embodiment of the present invention to the back surface of the work; a step of heating the first laminated composite sheet with the peripheral edge of the first laminated composite sheet attached to the fixing jig to harden the thermosetting protective film-forming film and form the protective film, thereby producing a second laminated composite sheet configured by stacking the protective film and the workpiece in this order in the thickness direction on the support sheet; dividing the workpiece in the second laminated composite sheet on the support sheet and cutting the protective film to produce a third laminated composite sheet on which a plurality of chips with protective films are fixed on the support sheet; and picking up the protective film-equipped chip in the third laminated composite sheet by separating it from the support sheet.

[0266] In this specification, the term "workpiece" refers to a wafer or a semiconductor device panel. Examples of "wafers" include semiconductor wafers made of elemental semiconductors such as silicon, germanium, and selenium, and compound semiconductors such as GaAs, GaP, InP, CdTe, ZnSe, and SiC; and insulating wafers made of insulators such as sapphire and glass. The term "semiconductor device panel" refers to an assembly of a plurality of semiconductor devices, each of which has at least one electronic component sealed with a sealing resin layer, arranged side by side in a plane. A circuit is formed on one surface of each of these workpieces, and in this specification, the surface of the workpiece on which the circuit is formed is referred to as the "circuit surface," and the surface of the workpiece opposite the circuit surface is referred to as the "back surface." The work is divided into chips by means of dicing or the like. In this specification, as in the case of the work, the surface of the chip on which the circuit is formed is referred to as the "circuit side," and the surface of the chip opposite the circuit side is referred to as the "back side." Both the circuit surface of the workpiece and the circuit surface of the chip are provided with protruding electrodes such as bumps, pillars, etc. The protruding electrodes are preferably made of solder.

[0267] 5A to 5H are cross-sectional views for schematically explaining the method for manufacturing a chip with a protective film according to this embodiment. Here, the method for manufacturing a chip with a protective film will be explained using an example in which the composite sheet for forming a protective film 101 shown in FIG.

[0268] 5A and 5B , in the step of producing the first laminate composite sheet in the method for producing a chip with a protective film according to this embodiment, the jig adhesive layer 16 in the protective film-forming composite sheet 101 is attached to a fixing jig 18, and the thermosetting protective film-forming film 13 in the protective film-forming composite sheet 101 is attached to the back surface 9b of the workpiece 9, thereby producing a first laminate composite sheet 501 in which the thermosetting protective film-forming film 13 and the workpiece 9 are laminated in this order in the thickness direction on the support sheet 10. In FIG. 5B , the first surface 13a of the thermosetting protective film-forming film 13 in the protective film-forming composite sheet 101 is attached to the back surface 9b of the workpiece 9. The peripheral portion of the first laminate composite sheet 501 is attached to the fixing jig 18 by the jig adhesive layer 16.

[0269] The thermosetting protective film-forming film 13 in the protective film-forming composite sheet 101 can be attached to the workpiece 9 by a known method. For example, the thermosetting protective film-forming film 13 may be attached to the workpiece 9 while being heated.

[0270] Next, in the step of producing the second laminated composite sheet, the first laminated composite sheet 501 is heated with the peripheral edge of the first laminated composite sheet 501 attached to the fixing jig 18 (FIG. 5C). This hardens the thermosetting protective film-forming film 13 to form the protective film 13', thereby producing the second laminated composite sheet 502, which is configured by stacking the support sheet 10, the protective film 13', and the workpiece 9 in this order in the thickness direction, as shown in FIG. 5D.

[0271] Reference numeral 13a' denotes the surface of the protective film 13' that was the first surface 13a of the thermosetting protective film-forming film 13 (sometimes referred to as the "first surface" in this specification). Reference numeral 13b' denotes the surface of the protective film 13' that was the second surface 13b of the thermosetting protective film-forming film 13 (sometimes referred to as the "second surface" in this specification).

[0272] Since the adhesive layer for the jig 16 is formed using the adhesive sheet for fixing the jig according to the embodiment described above, even when the first laminated composite sheet 501 is heated, the adhesive force between the adhesive layer for the jig 16 and the fixing jig 18 is maintained, and after heating, lifting F from the fixing jig 18 as shown in Figure 6 is less likely to occur.

[0273] Laser marking may be performed by irradiating the thermosetting protective film-forming film 13 shown in Figure 5B with a laser through the support sheet 10 (through the support sheet 10), or by irradiating the protective film 13' shown in Figure 5D with a laser through the support sheet 10 (through the support sheet 10).

[0274] Next, in the step of producing the third laminated composite sheet, the second laminated composite sheet 502 is cooled, and then, as shown in Fig. 5E, the work 9 in the second laminated composite sheet 502 is divided on the support sheet 10, and the protective film 13' is cut. The work 9 is divided into individual pieces into a plurality of chips 90.

[0275] Dividing the workpiece 9 and cutting the protective film 13′ may be performed by a known method. For example, dividing the workpiece 9 and cutting the protective film 13′ can be performed consecutively by dicing such as blade dicing, laser dicing using laser irradiation, or water dicing using water containing an abrasive. The protective film 13' is cut along the outer periphery of the chip 90 regardless of the cutting method.

[0276] In this way, by dividing the workpiece 9 and cutting the protective film 13', a plurality of protective film-coated chips 901 are obtained, each chip including a chip 90 and a protective film 130' (sometimes simply referred to as a "protective film" in this specification) after cutting provided on the back surface 90b of the chip 90. Reference numeral 130b' denotes the surface of the protective film 130' after cutting that was the second surface 13b' of the protective film 13' (sometimes referred to as a "second surface" in this specification).

[0277] In the step of producing the third laminated composite sheet, third laminated composite sheet 503 is produced in which a plurality of chips 901 with protective film are fixed on support sheet 10 as described above.

[0278] Next, in the picking up step, as shown in FIG. 5F, chip 901 with protective film in third laminated composite sheet 503 is picked up by being pulled away from support sheet 10.

[0279] In the pick-up step, peeling occurs between second surface 130b' of protective film 130' in protective film-coated chip 901 and first surface 12a of adhesive layer 12 in support sheet 10.

[0280] Here, a case is shown in which a separating means 7 such as a vacuum collet is used to separate the protective film-coated chip 901 in the direction of arrow P. Note that a cross-sectional view of the separating means 7 is omitted here. The chip 901 with the protective film can be picked up by a known method.

[0281] In the picking up step, such picking up of the protective film-coated chips 901 is carried out for all of the target protective film-coated chips 901 .

[0282] In the method for manufacturing a chip with a protective film according to this embodiment, the intended chip with a protective film 901 is obtained by carrying out the steps up to the picking up step.

[0283] After the picking up step, the remaining fourth laminate composite sheet 504, which is obtained by separating the protective film-equipped chip 901 from the third laminate composite sheet 503, is attached to the fixing jig 18 by the jig adhesive layer 16, as shown in Fig. 5G. By peeling the fourth laminate composite sheet 504 from the fixing jig 18, as shown in Fig. 5H, the fixing jig 18 can be returned to the state shown in Fig. 5A and reused.

[0284] In the manufacturing method of the chip with protective film according to this embodiment, the adhesive layer for the jig 16 is formed using the adhesive sheet for fixing the jig according to the embodiment described above, so that when the fourth laminated composite sheet 504 is peeled off from the fixing jig 18, adhesive residue G on the side of the fixing jig 18 as shown in Figure 7 is less likely to occur.

[0285] The above description of the method for manufacturing a chip with a protective film according to this embodiment has been directed to a method for manufacturing a chip with a protective film according to this embodiment when using the composite sheet 101 for forming a protective film shown in Figure 2. However, in the method for manufacturing a chip with a protective film according to this embodiment, a composite sheet for forming a protective film other than the composite sheet 101 for forming a protective film of this embodiment, such as the composite sheet 102 for forming a protective film or the composite sheet 104 for forming a protective film shown in Figures 3 to 4, may also be used.

[0286] ◇ Manufacturing method of substrate device (method of using chip with protective film) After the chip with a protective film is obtained by the above-described manufacturing method, a substrate device can be manufactured in the same manner as the conventional method for manufacturing a substrate device, except that this chip with a protective film is used instead of the conventional chip with a protective film.

[0287] For example, a manufacturing method can be mentioned that includes a flip-chip connection step in which a chip with a protective film obtained using the thermosetting protective film-forming film is picked up from a support sheet, and the protruding electrodes on the chip with a protective film are brought into contact with connection pads on a circuit board, thereby electrically connecting the protruding electrodes and the connection pads on the circuit board. [Example]

[0288] The present invention will be described in more detail below with reference to specific examples, although the present invention is not limited to the examples shown below. The contents of all components other than methyl ethyl ketone and toluene shown below are the contents of the target substance excluding the solvent.

[0289] (Adhesive composition for jig 1) An acrylic polymer (weight average molecular weight 1,800,000, glass transition temperature Tg: -54°C) (100 parts by mass) obtained by copolymerizing butyl acrylate (BA, 99 parts by mass) and 4-hydroxybutyl acrylate (4HBA, 1 part by mass) as the adhesive resin (i), a xylylene diisocyanate (XDI)-based crosslinking agent (manufactured by Soken Chemical & Engineering Co., Ltd., trade name "TD-75", solid content 75% by mass (solid content 0.2 parts by mass) as the crosslinking agent (ii), a carbon black-containing resin ("Multilac (registered trademark) A-903 Black" manufactured by Toyocolor Co., Ltd., 5.13 parts by mass (including 1.28 parts by mass of pigment)) as the pigment, and toluene as the solvent were stirred to prepare a jig adhesive composition 1 having a solid content of 30% by mass.

[0290] (Adhesive composition for jig 2) Adhesive composition for jigs 2 was prepared in the same manner as adhesive composition for jigs 1, except that the solid content of the crosslinking agent (ii) was changed from 0.2 parts by mass to 0.1 parts by mass.

[0291] (Adhesive composition for jig 3) Adhesive composition for jig 3 was prepared in the same manner as adhesive composition for jig 1, except that the solid content of the crosslinking agent (ii) was changed from 0.2 parts by mass to 0.05 parts by mass.

[0292] (Adhesive composition for jig 4) Adhesive composition for jig 4 was prepared in the same manner as adhesive composition for jig 1, except that the solid content of crosslinking agent (ii) was changed from 0.2 parts by mass to 0.3 parts by mass.

[0293] (Adhesive composition for jig 5) Adhesive composition for jigs 5 was prepared in the same manner as adhesive composition for jigs 1, except that the acrylic polymer (weight average molecular weight 1,800,000, glass transition temperature Tg: -54°C) of adhesive resin (i) in adhesive composition for jigs 1 was changed to an acrylic polymer of the same composition (weight average molecular weight 520,000, glass transition temperature Tg: -54°C).

[0294] (Adhesive composition for jig 6) Adhesive composition for jigs 6 was prepared in the same manner as adhesive composition for jigs 1, except that the acrylic polymer (weight average molecular weight 1,800,000, glass transition temperature Tg: -54°C) of adhesive resin (i) in adhesive composition for jigs 1 was changed to an acrylic polymer of the same composition (weight average molecular weight 2,040,000, glass transition temperature Tg: -54°C).

[0295] (Adhesive composition for jig 7) An acrylic polymer (weight average molecular weight 530,000, glass transition temperature Tg: -44°C) (100 parts by mass) obtained by copolymerizing butyl acrylate (BA, 86 parts by mass), methyl methacrylate (MMA, 8 parts by mass), acrylic acid (AA, 1 part by mass), and 2-hydroxyethyl acrylate (HEA, 5 parts by mass) as the adhesive resin (i), a tolylene diisocyanate (TDI)-based crosslinking agent (manufactured by Toyochem Co., Ltd., product name "BHS8515", solid content concentration 37.5% by mass) as the crosslinking agent (ii) (solid content 1.13 parts by mass), a carbon black-containing resin ("Multilac (registered trademark) A-903 Black" manufactured by Toyocolor Co., Ltd., 5.16 parts by mass (including 1.29 parts by mass of pigment)) as the pigment, and toluene as the solvent were stirred to prepare a jig adhesive composition 7 having a solid content concentration of 30% by mass.

[0296] (Adhesive composition for jig 8) An acrylic polymer (weight average molecular weight 300,000, glass transition temperature Tg: -2.3°C) (100 parts by mass) obtained by copolymerizing 2-ethylhexyl methacrylate (2EHMA, 80 parts by mass), methyl methacrylate (MMA, 10 parts by mass), and 2-hydroxyethyl acrylate (HEA, 10 parts by mass) as the adhesive resin (i), a tolylene diisocyanate (TDI)-based crosslinking agent (manufactured by Toyochem Co., Ltd., product name "BHS8515", solid content concentration 37.5% by mass) as the crosslinking agent (ii) (solid content 1.02 parts by mass), a carbon black-containing resin ("Multilac (registered trademark) A-903 Black" manufactured by Toyocolor Co., Ltd., 5.64 parts by mass (including 1.41 parts by mass of pigment)) as the pigment, and toluene as the solvent were stirred to prepare a jig adhesive composition 8 having a solid content concentration of 30% by mass.

[0297] (Adhesive composition for jig 9) An acrylic polymer (weight average molecular weight 500,000, glass transition temperature Tg: -38°C) (100 parts by mass) obtained by copolymerizing butyl acrylate (BA, 69.5 parts by mass), methyl methacrylate (MMA, 30 parts by mass), and 2-hydroxyethyl acrylate (HEA, 0.5 parts by mass) as the adhesive resin (i), a tolylene diisocyanate (TDI)-based crosslinking agent (manufactured by Toyochem Co., Ltd., product name "BHS8515", solid content concentration 37.5% by mass) as the crosslinking agent (ii), a carbon black-containing resin ("Multilac (registered trademark) A-903 Black" manufactured by Toyocolor Co., Ltd., 5.16 parts by mass (including 1.29 parts by mass of pigment)) as the pigment, and toluene as the solvent were stirred to prepare a jig adhesive composition 9 having a solid content concentration of 30% by mass.

[0298] (Adhesive composition for jig 10) An acrylic polymer (weight average molecular weight 600,000, glass transition temperature Tg: -37°C) (100 parts by mass) obtained by copolymerizing butyl acrylate (BA, 68.5 parts by mass), methyl methacrylate (MMA, 30 parts by mass), acrylamide (AAm, 1 part by mass), and 2-hydroxyethyl acrylate (HEA, 0.5 parts by mass) was used as the adhesive resin (i). A tolylene diisocyanate (TDI)-based crosslinking agent (manufactured by Toyochem Co., Ltd., product name "BHS8515", solids concentration 37.5% by mass) (solids content 4.89 parts by mass) was used as the crosslinking agent (ii). A 30% by mass solids concentration adhesive composition 10 for jigs was prepared by stirring the resulting mixture with toluene as the solvent.

[0299] (Adhesive composition for jig 11) An acrylic polymer (weight average molecular weight 1,800,000, glass transition temperature Tg: -54°C) (100 parts by mass) obtained by copolymerizing butyl acrylate (BA, 99 parts by mass) and 4-hydroxybutyl acrylate (4HBA, 1 part by mass) as the adhesive resin (i), a xylylene diisocyanate (XDI)-based crosslinking agent (manufactured by Soken Chemical & Engineering Co., Ltd., trade name "TD-75", solid content concentration 75% by mass (solid content 5 parts by mass) as the crosslinking agent (ii), a carbon black-containing resin ("Multilac (registered trademark) A-903 Black" manufactured by Toyocolor Co., Ltd., 13.75 parts by mass (including 3.43 parts by mass of pigment)) as the pigment, and toluene as the solvent were stirred to prepare an adhesive composition 11 for a jig having a solid content concentration of 30% by mass.

[0300] (Adhesive composition for jig 12) The adhesive resin (i) was an acrylic polymer (weight average molecular weight 300,000, glass transition temperature Tg: -25°C) (100 parts by mass) obtained by copolymerizing 2-ethylhexyl acrylate (2EHA, 30 parts by mass), 2-ethylhexyl methacrylate (2EHMA, 50 parts by mass), methyl methacrylate (MMA, 10 parts by mass), and 2-hydroxyethyl acrylate (HEA, 10 parts by mass). The crosslinking agent (ii) was tolylene. A diisocyanate (TDI) crosslinking agent (manufactured by Toyochem Co., Ltd., product name "BHS8515", solid content concentration 37.5% by mass) (solid content 0.51 parts by mass), a carbon black-containing resin as a pigment ("Multilac (registered trademark) A-903 Black", manufactured by Toyocolor Co., Ltd., 5.59 parts by mass (including 1.39 parts by mass of pigment)), and toluene as a solvent were stirred to prepare a pressure-sensitive adhesive composition 12 for jigs with a solid content concentration of 30% by mass.

[0301] [Example 1] In Example 1, a jig fixing pressure-sensitive adhesive sheet 1 shown in FIG. 1 and a protective film-forming composite sheet 101 including a thermosetting protective film-forming film shown in FIG. 2 were produced as follows.

[0302] (1) Preparation of adhesive sheet for fixing the jig The first release film was a 38 μm-thick polyethylene terephthalate (PET) film with a silicone-based release agent layer formed on one side thereof (SP-PET381031 manufactured by Lintec Corporation). The pressure-sensitive adhesive composition 1 for jigs obtained above was applied to the release-treated surface of the film, and the film was dried by heating at 115° C. for 3 minutes, thereby forming a 5 μm-thick first pressure-sensitive adhesive layer on the release-treated surface of the first release film. The exposed surface of the first pressure-sensitive adhesive layer was attached to one first side of a core film made of unstretched polypropylene (manufactured by Nihon Matai Co., Ltd., thickness 40 μm) that had been corona-treated on both sides. Subsequently, the same jig pressure-sensitive adhesive composition 1 obtained above was applied to the release-treated surface of a release film (manufactured by Lintec Corporation, product name "SP-PET381130"), which was a 38-μm-thick polyethylene terephthalate (PET) film with a silicone-based release agent layer formed on one side thereof, serving as a second release film. The jig pressure-sensitive adhesive composition 1 was then applied to the release-treated surface of the second release film, and the film was dried by heating at 115°C for 3 minutes, thereby forming a 5-μm-thick second pressure-sensitive adhesive layer on the release-treated surface of the second release film. The exposed surface of the second pressure-sensitive adhesive layer was attached to the other, second surface of the core film, thereby producing the jig-fixing pressure-sensitive adhesive sheet of Example 1, which was configured by laminating the first pressure-sensitive adhesive layer, core film, and second pressure-sensitive adhesive layer in this order in the thickness direction. The jig-fixing pressure-sensitive adhesive sheet of Example 1 was formed by laminating the first release film, first pressure-sensitive adhesive layer, core film, second pressure-sensitive adhesive layer, and second release film in this order.

[0303] (2) Preparation of a first laminate including a thermosetting protective film-forming film The following components (a) to (g) were mixed and diluted with methyl ethyl ketone to a solids concentration of 50% by mass to prepare a composition for forming a protective film.

[0304] (a) Polymer component: 120 parts by mass (solids equivalent, same below) of (meth)acrylic acid ester copolymer (a copolymer obtained by copolymerizing 20 parts by mass of n-butyl acrylate, 50 parts by mass of methyl acrylate, 15 parts by mass of glycidyl methacrylate, and 15 parts by mass of 2-hydroxyethyl acrylate, weight average molecular weight: 800,000, glass transition temperature: -5.6°C) (b-1) Thermosetting component: 75 parts by mass of bisphenol A epoxy resin (manufactured by Mitsubishi Chemical Corporation, product name "jER828", epoxy equivalent 184 to 194 g / eq) (b-2) Thermosetting component: 25 parts by mass of bisphenol A epoxy resin (manufactured by Mitsubishi Chemical Corporation, product name "jER1055", epoxy equivalent 800 to 900 g / eq) (c) Heat-activated latent epoxy resin curing agent: dicyandiamide (ADEKA Corporation: ADEKA Hardner EH3636AS, active hydrogen content 21 g / eq) 3 parts by mass (d) Curing accelerator: 2-phenyl-4,5-dihydroxymethylimidazole (manufactured by Shikoku Chemicals Corporation, product name "Curezol 2PHZ") 3 parts by mass (e) Filler: Silica filler (manufactured by Admatechs Co., Ltd., product name "SC2050MA", average particle size: 0.5 μm) 290 parts by mass (f) Colorant: Carbon black (manufactured by Mitsubishi Chemical Corporation, product name "#MA650", average particle size: 28 nm) 1.2 parts by mass (g) Silane coupling agent: (manufactured by Shin-Etsu Chemical Co., Ltd., product name "KBM-403") 2 parts by mass

[0305] A release film (manufactured by Lintec Corporation, product name "SP-PET381031") was prepared as the third release film, and a release film (manufactured by Lintec Corporation, product name "SP-PET381130") was prepared as the fourth release film.

[0306] First, the protective film-forming composition was applied to the release surface of the third release film using a knife coater so that the thickness of the thermosetting protective film-forming film finally obtained would be 25 μm, and then dried to form a thermosetting protective film-forming film. Thereafter, the release surface of the fourth release film was placed on the thermosetting protective film-forming film and the two were bonded together to obtain a first laminate consisting of the third release film, the thermosetting protective film-forming film (thickness: 25 μm), and the fourth release film.

[0307] (3) Preparation of a second laminate including a support sheet The following components (h) and (i) were mixed and diluted with methyl ethyl ketone to a solids concentration of 25 mass % to prepare a pressure-sensitive adhesive composition.

[0308] (h) Adhesive base: 100 parts by mass of (meth)acrylic acid ester copolymer (a copolymer obtained by copolymerizing 60 parts by mass of 2-ethylhexyl acrylate, 30 parts by mass of methyl methacrylate, and 10 parts by mass of 2-hydroxyethyl acrylate, weight average molecular weight: 600,000) (i) Crosslinking agent: 20 parts by mass of a xylene diisocyanate adduct of trimethylolpropane (manufactured by Mitsui Takeda Chemicals, Inc., product name "Takenate D110N")

[0309] As the fifth release film, a release film (manufactured by Lintec Corporation, product name "SP-PET381031") was prepared, which was made by forming a silicone-based release agent layer on one side of a 38 μm-thick PET film.

[0310] The aforementioned pressure-sensitive adhesive composition was hand-coated onto the release surface of the fifth release film so that the final pressure-sensitive adhesive layer would have a thickness of 5 μm, and then dried in an oven at 100° C. for 1 minute to form a pressure-sensitive adhesive layer. A polypropylene film (thickness: 80 μm) was then attached to the pressure-sensitive adhesive layer as a substrate to obtain a second laminate consisting of a support sheet made of the substrate and pressure-sensitive adhesive layer and the fifth release film.

[0311] (4) Preparation of the third laminate The fourth release film was peeled off from the first laminate obtained in (2) above to expose the thermosetting protective film-forming film. Meanwhile, the fifth release film was peeled off from the second laminate obtained in (3) above to expose the pressure-sensitive adhesive layer. The first laminate and the second laminate were bonded together at 0.5 m / min so that the exposed pressure-sensitive adhesive layer was in contact with the exposed thermosetting protective film-forming film, thereby obtaining a third laminate in which a support sheet consisting of a substrate and a pressure-sensitive adhesive layer, a thermosetting protective film-forming film, and a third release film were laminated.

[0312] (5) Preparation of composite sheet for forming protective film The second release film 152 was peeled off and removed from the jig fixation pressure-sensitive adhesive sheet 1 of Example 1. Next, a circular punching blade was applied from the side of the second pressure-sensitive adhesive layer 163 to cut the inner peripheral edges of the first pressure-sensitive adhesive layer 161, core film 162, and second pressure-sensitive adhesive layer 163, leaving the first release film 151, and the inner circular portions were removed, to produce a fourth laminate in which the first pressure-sensitive adhesive layer 161, core film 162, and second pressure-sensitive adhesive layer 163, from which the inner circular portions had been removed, were laminated in this order on the first release film 151. At this time, the diameter of the inner peripheral edges of the first pressure-sensitive adhesive layer 161, core film 162, and second pressure-sensitive adhesive layer 163 was 185 mm.

[0313] The third release film was peeled from the third laminate, and the exposed thermosetting protective film-forming film 13 was bonded to the second pressure-sensitive adhesive layer 163 of the fourth laminate, which had been exposed by removing the inner circular portion, at a speed of 0.5 m / min. A circular punching blade was then applied from the substrate 11 side to the outside, concentrically with the inner circular portion, to punch out the outer periphery of the support sheet 10, which was made of the substrate 11 and the pressure-sensitive adhesive layer 12, the thermosetting protective film-forming film 13, the second pressure-sensitive adhesive layer 163, the core film 162, and the first pressure-sensitive adhesive layer 161, leaving the first release film 151 of the jig fixing pressure-sensitive adhesive sheet 1. The outer periphery was then removed to produce the composite sheet 101 for protective film formation of Example 1. The diameter of the outer periphery of the composite sheet 101 for protective film formation of Example 1, which had the jig pressure-sensitive adhesive layer 16, was 210 mm.

[0314] The composite sheet 101 for forming a protective film of Example 1 comprises an adhesive sheet (i.e., support sheet 10) having an adhesive layer 12 (thickness: 5 μm) laminated on a substrate 11, a thermosetting protective film-forming film 13 laminated on the adhesive layer 12 side of the adhesive sheet, an annular jig adhesive layer 16 laminated on the peripheral portion of the thermosetting protective film-forming film 13 on the side opposite the adhesive sheet, and a first release film 151 laminated on the jig adhesive layer 16 on the side opposite the thermosetting protective film-forming film 13. The composite sheet 101 for forming a protective film of Example 1 corresponds to the structure of FIG. 2 having a release film.

[0315] [Examples 2 to 6] The jig fixing adhesive sheets of Examples 2 to 6 were prepared in the same manner as the jig fixing adhesive sheet of Example 1, except that jig fixing adhesive composition 1 in the jig fixing adhesive sheet of Example 1 was changed to jig fixing adhesive compositions 2 to 6.

[0316] The composite sheets for forming protective films of Examples 2 to 6 were produced in the same manner as the composite sheet for forming protective films of Example 1, except that in the composite sheet for forming protective films of Example 1, the adhesive sheet for fixing the jig of Example 1 was changed to the adhesive sheet for fixing the jig of Examples 2 to 6.

[0317] [Example 7] The adhesive sheet for jig fixing of Example 7 was produced in the same manner as the adhesive sheet for jig fixing of Example 1, except that in the adhesive sheet for jig fixing of Example 1, adhesive composition for jig 1 was changed to adhesive composition for jig 7, and the unstretched polypropylene film that had been subjected to double-sided corona treatment as the core film was changed to a polypropylene film that had been subjected to double-sided corona treatment (melt extrusion molded product, manufactured by Diaplus Film Co., Ltd., thickness 50 μm).

[0318] The composite sheet for forming a protective film of Example 7 was produced in the same manner as the composite sheet for forming a protective film of Example 1, except that in the composite sheet for forming a protective film of Example 1, the adhesive sheet for fixing the jig of Example 1 was changed to the adhesive sheet for fixing the jig of Example 7.

[0319] [Example 8] The adhesive sheet for jig fixing of Example 7 was produced in the same manner as the adhesive sheet for jig fixing of Example 1, except that in the adhesive sheet for jig fixing of Example 1, adhesive composition for jig 1 was changed to adhesive composition for jig 7, and the unstretched polypropylene film that had been subjected to double-sided corona treatment as the core film was changed to a polyolefin-based thermoplastic elastomer film that had been subjected to double-sided corona treatment (manufactured by Kurabo Industries Co., Ltd., product number ``PB-0107'', thickness 30 μm).

[0320] The composite sheet for forming a protective film of Example 7 was produced in the same manner as the composite sheet for forming a protective film of Example 1, except that in the composite sheet for forming a protective film of Example 1, the adhesive sheet for fixing the jig of Example 1 was changed to the adhesive sheet for fixing the jig of Example 7.

[0321] [Example 9] The adhesive sheet for jig fixing of Example 9 was prepared in the same manner as the adhesive sheet for jig fixing of Example 1, except that in the adhesive sheet for jig fixing of Example 1, adhesive composition for jig 1 was changed to adhesive composition for jig 8.

[0322] The composite sheet for forming a protective film of Example 9 was produced in the same manner as the composite sheet for forming a protective film of Example 1, except that in the composite sheet for forming a protective film of Example 1, the adhesive sheet for fixing the jig of Example 1 was changed to the adhesive sheet for fixing the jig of Example 9.

[0323] [Comparative Example 1] The adhesive sheet for jig fixing of Comparative Example 1 was prepared in the same manner as the adhesive sheet for jig fixing of Example 1, except that in the adhesive sheet for jig fixing of Example 1, adhesive composition for jig 1 was changed to adhesive composition for jig 9.

[0324] The composite sheet for forming a protective film of Comparative Example 1 was produced in the same manner as the composite sheet for forming a protective film of Example 1, except that in the composite sheet for forming a protective film of Example 1, the adhesive sheet for fixing the jig of Example 1 was changed to the adhesive sheet for fixing the jig of Comparative Example 1.

[0325] Comparative Example 2 The adhesive sheet for jig fixation of Comparative Example 2 was produced in the same manner as the adhesive sheet for jig fixation of Example 1, except that in the adhesive sheet for jig fixation of Example 1, adhesive composition for jig 1 was changed to adhesive composition for jig 10, and the unstretched polypropylene film that had been subjected to double-sided corona treatment as the core film was changed to a polyvinyl chloride film that had been subjected to double-sided corona treatment (manufactured by Okamoto Corporation, product number ``PVC50OSGP42B'', thickness 50 μm).

[0326] The composite sheet for forming a protective film of Comparative Example 2 was produced in the same manner as the composite sheet for forming a protective film of Example 1, except that in the composite sheet for forming a protective film of Example 1, the adhesive sheet for fixing the jig of Example 1 was changed to the adhesive sheet for fixing the jig of Comparative Example 2.

[0327] [Comparative Examples 3 to 4] The adhesive sheets for jig fixing of Comparative Examples 3 and 4 were prepared in the same manner as the adhesive sheet for jig fixing of Example 1, except that the adhesive composition for jig fixing 1 in the adhesive sheet for jig fixing of Example 1 was changed to adhesive compositions for jig fixing 11 and 12.

[0328] The composite sheets for forming protective films of Comparative Examples 3 and 4 were produced in the same manner as the composite sheet for forming protective films of Example 1, except that in the composite sheet for forming protective films of Example 1, the adhesive sheet for fixing the jig of Example 1 was changed to the adhesive sheet for fixing the jig of Comparative Examples 3 and 4.

[0329] <Environmental friendliness> The jig fixing pressure-sensitive adhesive sheets of Examples 1 to 9 and the composite sheets for forming a protective film of Examples 1 to 9 use a non-polyvinyl chloride plastic film as the core film, which reduces the environmental impact. The jig fixing pressure-sensitive adhesive sheet of Comparative Example 2 and the composite sheet for forming a protective film of Comparative Example 2 use a polyvinyl chloride plastic film as the core film, which increases the environmental impact. Tables 1 and 2 show the environmental compliance based on the following standards. A: A non-polyvinyl chloride plastic film is used as the core film. C: A polyvinyl chloride plastic film is used as the core film.

[0330] <Adhesion strength measurement to SUS before heating> The third release film was peeled off from the third laminate, which was formed by laminating a support sheet consisting of a substrate and an adhesive layer, a thermosetting protective film-forming film, and a third release film, to expose the thermosetting protective film-forming film. The second release film was peeled off from each of the jig fixation pressure-sensitive adhesive sheets of Examples 1 to 9 and Comparative Examples 1 to 4 to expose the second pressure-sensitive adhesive layer. The exposed thermosetting protective film-forming film of the third laminate was bonded to the exposed second adhesive layer of the jig fixing adhesive sheet of Examples 1 to 9 and Comparative Examples 1 to 4, respectively, to produce the fifth laminates of Examples 1 to 9 and Comparative Examples 1 to 4. The fifth laminates of Examples 1 to 9 and Comparative Examples 1 to 4 were cut to a size of 25 mm wide and 150 mm long, and then the first release film was peeled off to expose the first adhesive layer, thereby producing test pieces of Examples 1 to 9 and Comparative Examples 1 to 4. The exposed first adhesive layer of each test piece from Examples 1 to 9 and Comparative Examples 1 to 4 was attached to the mirror-finished surface of SUS304 by rolling a 2 kg roller back and forth once, and then allowed to stand for 30 minutes at 23°C and 50% RH. Next, using a universal tensile tester (Shimadzu Corporation, "Autograph"), also at 23°C and 50% RH, the test piece was peeled from the SUS304 at a peeling speed of 300 mm / min so that the surfaces of the first adhesive layer of the test piece and the SUS304 that had been in contact with each other formed an angle of 180°. The peel strength between the first adhesive layer of the test piece and the SUS304 was measured at this time. The test piece was peeled over a length of 100 mm, and the average of the measurements excluding the first and last 10 mm lengths was taken as the adhesive strength to SUS before heating (mN / 25 mm). The results are shown in Tables 1 and 2.

[0331] <Adhesion strength measurement to SUS after heating> The exposed first adhesive layer of each test piece from Examples 1 to 9 and Comparative Examples 1 to 4 was attached to the mirror-finished surface of SUS304 by rolling a 2 kg roller back and forth once, and then heated at 130°C for 2 hours. After cooling, the peel strength between the first adhesive layer of the test piece and SUS304 was measured in the same manner as in the measurement of adhesive strength to SUS before heating, and the adhesive strength to SUS after heating (mN / 25 mm) was calculated. The results are shown in Tables 1 and 2.

[0332] <Adhesion test to core material before heating> The second release film was peeled off from each of the jig fixation pressure-sensitive adhesive sheets of Examples 1 to 9 and Comparative Examples 1 to 4 to expose the second pressure-sensitive adhesive layer. An adhesive tape (product number "PET50PL Thin", manufactured by Lintec Corporation) with a 50 μm thick polyethylene terephthalate film as a substrate was prepared. The adhesive surface of this adhesive tape was attached to the exposed second adhesive layer of the jig fixation adhesive sheet of each of Examples 1 to 9 and Comparative Examples 1 to 4 to produce the sixth laminates of Examples 1 to 9 and Comparative Examples 1 to 4. The first release film of the sixth laminate of Examples 1 to 9 and Comparative Examples 1 to 4 was peeled off, and 100 5 mm square cuts were made with a cutter from the exposed first pressure-sensitive adhesive layer side in an area of ​​50 mm x 50 mm to prepare test specimens for adhesion tests of Examples 1 to 9 and Comparative Examples 1 to 4. Cellotape (registered trademark) (product number "LP-24") manufactured by Nichiban Co., Ltd. was applied to the cut surfaces of the test specimens of Examples 1 to 9 and Comparative Examples 1 to 4, and after leaving them to stand for 20 minutes, the cellotape was peeled off. Test specimens of Examples 1 to 9 and Comparative Examples 1 to 4 were prepared.

[0333] The adhesion to the core material before heating was evaluated according to the following criteria. The results are shown in Tables 1 and 2. A: There was no peeling in an area of ​​50 mm x 50 mm. B: Peeling occurred in an area of ​​10% or less of a 50 mm x 50 mm region. C: Peeling occurred in an area of ​​more than 10% of the 50 mm x 50 mm area.

[0334] (Adhesion test to core material after heating) The sixth laminates of Examples 1 to 9 and Comparative Examples 1 to 4 were heated at 130°C for 2 hours. After cooling, the first release film of the sixth laminates of Examples 1 to 9 and Comparative Examples 1 to 4 was peeled off, and 100 5mm square cuts were made with a cutter from the exposed first pressure-sensitive adhesive layer side in an area of ​​50 mm x 50 mm to prepare test specimens for adhesion tests of Examples 1 to 9 and Comparative Examples 1 to 4. Cellotape (registered trademark) (product number "LP-24") manufactured by Nichiban Co., Ltd. was applied to the cut surfaces of the test specimens of Examples 1 to 9 and Comparative Examples 1 to 4, and after leaving them to stand for 20 minutes, the cellotape was peeled off. Test specimens of Examples 1 to 9 and Comparative Examples 1 to 4 were prepared.

[0335] The adhesion to the core material after heating was evaluated according to the following criteria. The results are shown in Tables 1 and 2. A: There was no peeling in an area of ​​50 mm x 50 mm. B: Peeling occurred in an area of ​​10% or less of a 50 mm x 50 mm region. C: Peeling occurred in an area of ​​more than 10% of the 50 mm x 50 mm area.

[0336] <Ring frame suitability> (Float evaluation) The first release film was peeled off from each of the composite sheets for forming a protective film of Examples 1 to 9 and Comparative Examples 1 to 4, and the exposed first adhesive layer of the adhesive layer for the jig was placed on a dicing ring frame and pressed through a laminator at 70°C and 0.3 m / min. The composite sheet for forming a protective film attached to the dicing ring frame was heated at 130° C. for 2 hours to cure the thermosetting protective film-forming film, and then allowed to cool.

[0337] The state of lifting of the composite sheet for forming a protective film from the ring frame was observed over the entire contact area between the first adhesive layer of the jig adhesive layer and the ring frame. Lifting on the outside of the ring frame could be directly observed from the appearance of the composite sheet for forming a protective film, and lifting on the inside of the ring frame could be observed from the appearance of wrinkles on the composite sheet for forming a protective film. The ratio of the area where lifting occurred to the entire area of ​​the contact area was calculated, and the lifting after heating was evaluated according to the following criteria. The results are shown in Tables 1 and 2. A: The percentage of the area where lifting occurred was less than 1%. B: The percentage of the area where lifting occurred was 1% or more and less than 15%. C: The percentage of the area where lifting occurred was 15% or more and less than 40%. D: The percentage of the area where lifting occurred was 40% or more and less than 70%. E: The percentage of the area where lifting occurred was 70% or more.

[0338] (Evaluation of adhesive residue) After evaluation of lifting, the composite sheets for forming a protective film of Examples 1 to 9 and Comparative Examples 1 to 4 were peeled off from the ring frame. After peeling, the state of adhesive residue on the ring frame was observed. The ratio of the area with adhesive residue to the total area of ​​the area where the ring frame had been in contact was calculated, and the adhesive residue was evaluated according to the following criteria. The results are shown in Tables 1 and 2. A: The percentage of the area where adhesive residue occurred was less than 1%. B: The percentage of the area where adhesive residue occurred was 1% or more and less than 15%. C: The percentage of the area where adhesive residue occurred was 15% or more and less than 40%. D: The percentage of the area where adhesive residue occurred was 40% or more and less than 70%. E: The percentage of the area where adhesive residue occurred was 70% or more.

[0339] [Table 1]

[0340] [Table 2]

[0341] The adhesive sheets for jig fixing of Examples 1 to 9 and the composite sheets for protective film formation of Examples 1 to 9 formed using these sheets use a non-polyvinyl chloride plastic film as the core film, which reduces the environmental impact, and when used to manufacture chips with protective films, after heating, they are less likely to lift off from the fixing jig 18 as shown in Figure 6, and are less likely to leave adhesive residue G on the side of the fixing jig 18 as shown in Figure 7, making them easy to peel off from the fixing jig. [Industrial Applicability]

[0342] The present invention can be used in the manufacture of various substrate devices, including semiconductor devices. [Explanation of symbols]

[0343] 1...Adhesive sheet for fixing jigs, 10, 20... Support sheet, 10a... One side (first side) of the support sheet, 11... Base material, 12... Pressure-sensitive adhesive layer, 13, 23... Thermosetting protective film-forming film, 13'... Protective film, 13a'... One side (first side) of the protective film, 13b'... Other side (second side) of the protective film, 130'... Protective film after cutting, 101, 102, 104... Composite sheet for forming protective film, 15... Release film, 151... First release film, 152... Second release film, 16... Pressure-sensitive adhesive layer for jig, 161... First pressure-sensitive adhesive layer, 163... Second pressure-sensitive adhesive layer, 162... Core film, 18... Fixing jig, 501...first laminated composite sheet, 502...second laminated composite sheet, 503...third laminated composite sheet, 504...fourth laminated composite sheet, 9...workpiece, 9b...back surface of workpiece, 90...chip, 90b...back surface of chip, 901...chip with protective film, F: Lifted, G: Glue residue

Claims

1. An adhesive sheet for fixing a jig used in a composite sheet for forming a protective film, the adhesive sheet comprising: a support sheet; a thermosetting protective film forming film provided on one side of the support sheet; and an adhesive layer for a jig provided near the peripheral portion on the one side of the support sheet or on a first side of the thermosetting protective film forming film opposite the support sheet, the composite sheet for forming a protective film is one in which the pressure-sensitive adhesive layer for a jig is formed using the pressure-sensitive adhesive sheet for jig fixing, the jig-fixing pressure-sensitive adhesive sheet is configured by laminating a first pressure-sensitive adhesive layer, a core film, and a second pressure-sensitive adhesive layer in this order in a thickness direction; The core film is made of a non-polyvinyl chloride plastic film, The pressure-sensitive adhesive sheet for jig fixation has a 180° peeling adhesive strength to SUS304 after heating at 130°C for 2 hours of 4.0 to 25 N / 25 mm.

2. The jig-fixing pressure-sensitive adhesive sheet according to claim 1 , wherein the core film is made of a material containing a polyolefin other than polyethylene or a polyolefin-based thermoplastic elastomer.

3. The jig-fixing pressure-sensitive adhesive sheet according to claim 2 , wherein the core film is made of a material containing unstretched polypropylene.

4. The pressure-sensitive adhesive sheet for jig fixation according to any one of claims 1 to 3, wherein the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer are formed from a pressure-sensitive adhesive composition for a jig containing an acrylic resin, and the weight-average molecular weight of the acrylic resin is 800,000 or more.

5. A composite sheet for forming a protective film, comprising: a support sheet; a thermosetting protective film-forming film provided on one surface of the support sheet; and a jig adhesive layer provided near a peripheral portion on the one surface of the support sheet or on a first surface of the thermosetting protective film-forming film opposite to the support sheet, the pressure-sensitive adhesive layer for a jig is formed using a pressure-sensitive adhesive sheet for a jig fixation, the jig-fixing pressure-sensitive adhesive sheet is configured by laminating a first pressure-sensitive adhesive layer, a core film, and a second pressure-sensitive adhesive layer in this order in a thickness direction; The core film is made of a non-polyvinyl chloride plastic film, The adhesive sheet for fixing a jig is a composite sheet for forming a protective film, which has a 180° peeling adhesive strength to SUS304 after heating at 130°C for 2 hours of 4.0 to 25 N / 25 mm.

6. A method for manufacturing a chip with a protective film, the method comprising: a step of attaching a jig adhesive layer in the composite sheet for forming a protective film to a fixing jig and attaching a thermosetting protective film-forming film in the composite sheet for forming a protective film according to claim 5 to the back surface of a workpiece, thereby producing a first laminated composite sheet in which the thermosetting protective film-forming film and the workpiece are laminated in this order in the thickness direction on the support sheet; a step of heating the first laminated composite sheet with the peripheral edge of the first laminated composite sheet attached to the fixing jig to harden the thermosetting protective film-forming film and form the protective film, thereby producing a second laminated composite sheet configured by stacking the protective film and the workpiece in this order in the thickness direction on the support sheet; dividing the work in the second laminated composite sheet on the support sheet and cutting the protective film to produce a third laminated composite sheet on which a plurality of chips with protective films are fixed on the support sheet; and picking up the protective film-coated chip in the third laminated composite sheet by separating it from the support sheet.

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