Resin sheet, method for using the resin sheet, and method for manufacturing cured sealed body with cured resin layer

Abstract

To provide a resin sheet which improves productivity and enables manufacture of a curable sealed body with a curable resin layer that suppresses warpage and has a flat surface.SOLUTION: A resin sheet has a base material, and a thermosetting resin layer formed of a thermosetting resin composition containing a polymerizable component (A) and a thermosetting component (B), in this order, has a storage elastic modulus E' at 23°C of the curable resin layer obtained by thermosetting the thermosetting resin layer of 1.0×107 to 1.0×1013 Pa, and is used in manufacture of a curable sealed body which includes: mounting a sealing object on the surface of the thermosetting resin layer; covering the sealing object and the surface of the thermosetting resin layer in at least the peripheral part of the sealing object with a sealing material; thermosetting the sealing material into a curable sealed body containing the sealing object; thermosetting the thermosetting resin layer into a curable resin layer; and removing the curable sealed body with the curable resin layer from the base material after the thermosetting the sealing material and the thermosetting resin layer.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a resin sheet, a method for using a resin sheet, and a method for producing a cured sealed body with a cured resin layer using the resin sheet. [Background technology]

[0002] 2. Description of the Related Art In recent years, as electronic devices become smaller and more functional, there is a demand for semiconductor packages to be smaller, more functional, and more reliable. Wafer-level packaging (WLP) technology, one of the technologies that can meet such demands, is a technology in which external electrodes, etc. are formed on the surface on which the chip circuit is formed before it is diced into individual pieces, and finally the package containing the chip is diced to create a surface-mountable chip-scale package (CSP) that can be miniaturized to the same scale as a semiconductor chip.

[0003] WLPs are divided into Fan-In type and Fan-Out type. In a Fan-Out type WLP, the semiconductor chip to be sealed is covered with a sealing material in an area larger than the size of the semiconductor chip to form a semiconductor chip sealing body, and then a redistribution layer and external electrodes are formed not only on the circuit surface of the semiconductor chip but also on the surface area of ​​the sealing material.

[0004] For example, Patent Document 1 describes a method for manufacturing a semiconductor package in which multiple semiconductor chips separated from a semiconductor wafer are surrounded by a molding material that is a sealing resin while leaving the circuit formation surface of the chips intact to form an extended wafer, and a rewiring pattern is formed by extending the rewiring pattern to an area outside the semiconductor chips. In the manufacturing method described in Patent Document 1, the silicon wafer is attached to a wafer mount tape for dicing and subjected to a dicing process, after which it is replaced with a wafer mount tape for expanding and subjected to a tape expanding process in which the wafer mount tape (support tape) is expanded to expand the distance between multiple silicon chips. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2010 / 058646 Summary of the Invention [Problem to be solved by the invention]

[0006] Incidentally, in the manufacture of a Fan-Out type WLP as described in Patent Document 1, a process is generally included in which the semiconductor chip, which is the object to be sealed, is covered with a sealing material, and the sealing material is heated to thermally harden the material, thereby sealing the semiconductor chip and forming a hardened sealing body. However, when the cured sealant obtained by thermally curing the sealant is separated from an adhesive tape, such as a wafer mount tape, that secures the sealant to the support, the cured sealant after separation may warp due to thermal shrinkage. If a hardened sealed body is warped and has an uneven surface, it is more likely to have problems such as cracks when it is ground in the next process, and when the hardened sealed body is transported by the device, problems are more likely to occur when the hardened sealed body is handed over by an arm.

[0007] In some cases, a resin film may be further provided on one surface of the cured sealed body to form a cured sealed body with a resin film. To manufacture such a cured sealed body with a resin film, it is usually necessary to go through the steps of attaching a separately prepared sheet for forming a resin film to one surface of the formed cured sealed body and curing the sheet for forming a resin film to form a resin film. In addition, as described above, the cured sealed body is prone to warping during production, and there are concerns that warping of the cured sealed body may reduce workability when attaching the resin film-forming sheet and reduce adhesion between the cured resin film and the cured sealed body. Furthermore, the resulting cured encapsulated body with a resin film may have even greater warpage, which may cause various problems in subsequent processes.

[0008] An object of the present invention is to provide a resin sheet to be used in the production of a cured sealed product, which can be produced with improved productivity to produce a cured sealed product with a cured resin film that is suppressed in warping and has a flat surface. [Means for solving the problem]

[0009] The present inventors have found that the above-mentioned problems can be solved by using a resin sheet having a thermosetting resin layer formed from a thermosetting resin composition containing a polymerizable component and a thermosetting component, in the manufacture of a cured sealed body containing the object to be sealed, by placing an object to be sealed on the surface of the thermosetting resin layer, coating it with a sealing material, and curing it.

[0010] That is, the present invention relates to the following [1] to [9]. [1] A thermosetting resin layer formed from a thermosetting resin composition containing a polymerizable component (A) and a thermosetting component (B), A resin sheet used for manufacturing a cured sealed body, comprising: placing an object to be sealed on a surface of the thermosetting resin layer; covering the object to be sealed and the surface of the thermosetting resin layer at least in the peripheral portion of the object to be sealed with a sealing material; and thermally curing the sealing material to form a cured sealed body including the object to be sealed. [2] The resin sheet according to the above [1], wherein when the sealing material is cured, the thermosetting resin layer is also cured, thereby forming a cured resin layer. [3] The resin sheet according to the above [1] or [2], wherein the content of the colorant in the thermosetting resin composition is less than 8 mass%. [4] The storage modulus E' at 23°C of the cured resin layer obtained by thermally curing the thermosetting resin layer is 1.0 × 10 7 ~1.0×10 13 The resin sheet according to any one of the above [1] to [3], wherein the viscosity is 100 Pa. [5] The resin sheet according to any one of the above [1] to [4], wherein the thermosetting resin layer has a thickness of 1 to 500 μm. [6] A method for using the resin sheet according to any one of the above [1] to [5], placing an object to be sealed on the surface of the thermosetting resin layer; covering the object to be sealed and at least a surface of the thermosetting resin layer in a peripheral portion of the object to be sealed with a sealing material; The sealing material is thermally cured to form a cured sealing body including the object to be sealed. How to use resin sheets. [7] A method for using the resin sheet according to the above item [6], wherein when the sealing material is thermally cured, the thermosetting resin layer is also thermally cured to form a cured resin layer, thereby forming a cured sealed body with a thermosetting resin layer. [8] A method for producing a cured sealed product with a cured resin layer, using the resin sheet described in any one of the above [1] to [5], the method comprising the following steps (i) to (iii): Step (i): A step of placing an object to be sealed on a part of the surface of the thermosetting resin layer of the resin sheet. Step (ii): A step of covering the object to be sealed and at least the surface of the thermosetting resin layer in the periphery of the object to be sealed with a sealing material. Step (iii): A step of thermally curing the sealing material to form a cured sealed body including the object to be sealed, and also thermally curing the thermosetting resin layer to form a cured resin layer, thereby obtaining a cured sealed body with a cured resin layer. Effect of the Invention

[0011] By using the resin sheet of the present invention in the production of a cured sealed article, a cured sealed article having a flat surface with reduced warping can be produced with improved productivity. [Brief description of the drawings]

[0012] [Figure 1] 1 is a schematic cross-sectional view of a resin sheet according to one embodiment of the present invention, showing a configuration of the resin sheet. FIG. [Diagram 2] FIG. 2 is a cross-sectional view showing a process for producing a cured sealed body with a cured resin layer using the resin sheet 1d shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] As used herein, the term "active ingredient" refers to the components contained in the target composition excluding diluent solvents. In this specification, the mass average molecular weight (Mw) is a value calculated as standard polystyrene measured by gel permeation chromatography (GPC), specifically, a value measured based on the method described in the examples. In this specification, for example, "(meth)acrylic acid" refers to both "acrylic acid" and "methacrylic acid", and similar terms. In this specification, the lower limit and upper limit described in stages for the preferred numerical range (e.g., range of content, etc.) can be independently combined. For example, the description "preferably 10 to 90, more preferably 30 to 60" can be combined with the "preferable lower limit (10)" and the "more preferable upper limit (60)" to form "10 to 60."

[0014] [Configuration of resin sheet] The resin sheet of the present invention has a thermosetting resin layer formed from a thermosetting resin composition containing a polymerizable component (A) and a thermosetting component (B). The resin sheet of one embodiment of the present invention may be a sheet having a single layer structure consisting of only a thermosetting resin layer, or may be a sheet having a multilayer structure having a thermosetting resin layer and a layer other than the thermosetting resin layer.

[0015] FIG. 1 is a schematic cross-sectional view of a resin sheet according to one embodiment of the present invention, showing the configuration of the resin sheet. An example of a resin sheet according to an embodiment of the present invention is a resin sheet 1a having a substrate 20 and a thermosetting resin layer 10, as shown in Fig. 1(a). By forming a resin sheet having a substrate like the resin sheet 1a, the self-supporting property can be improved, and the handling property can be improved.

[0016] In addition, in order to improve the adhesion between the substrate 20 and the thermosetting resin layer 10, the substrate 20, the adhesive layer 30, and the thermosetting resin layer 10 may be laminated in this order to form a resin sheet, as shown in FIG. 1(b) as the resin sheet 1b. The resin sheet 1b may have a configuration in which a release material is further laminated on the adhesive surface of the adhesive layer 30.

[0017] Moreover, an example of a resin sheet according to another embodiment of the present invention is a resin sheet 1c having a thermosetting resin layer 10 and a pressure-sensitive adhesive layer 30 as shown in FIG. 1(c). By having the adhesive layer 30 like the resin sheet 1c, the resin sheet can be sufficiently fixed to a support or the like, and the workability in the sealing step can be improved.

[0018] Alternatively, a resin sheet 1d shown in FIG. 1(d) may be formed by laminating a second pressure-sensitive adhesive layer 32, a substrate 20, a first pressure-sensitive adhesive layer 31, and a thermosetting resin layer 10 in this order. By using a configuration like resin sheet 1d, the resin sheet can be sufficiently fixed to a support or the like, and the adhesion between the substrate 20 and the thermosetting resin layer 10 can be improved, thereby making it easier to work in the sealing process. The resin sheet 1d may have a configuration in which a release material is further laminated on the adhesive surface of the second adhesive layer 32.

[0019] The resin sheet according to one embodiment of the present invention may further have a release material on the surface of the thermosetting resin layer, from the viewpoint of protecting the surface of the thermosetting resin layer. For example, a resin sheet according to one embodiment of the present invention may have a configuration in which a thermosetting resin layer is sandwiched between two release materials, or may have a configuration in which a release material is further laminated on the exposed surface of the thermosetting resin layer 10 of the resin sheets 1a, 1b, 1c, and 1d shown in FIG. 1. This release material is provided to protect the surface of the thermosetting resin layer and is removed when the resin sheet is used.

[0020] [Applications of resin sheets] The resin sheet of the present invention is used for producing a cured sealed body, in which an object to be sealed is placed on the surface of the thermosetting resin layer, the object to be sealed and the surface of the thermosetting resin layer at least in the peripheral portion of the object to be sealed are covered with a sealing material, and the sealing material is thermally cured to form a cured sealed body containing the object to be sealed. Specific aspects regarding the production of a cured sealed body using the resin sheet of the present invention will be described later.

[0021] For example, consider a case in which an object to be sealed is placed on the adhesive surface of an adhesive sheet such as a general wafer mount tape, as used in the manufacturing method described in Patent Document 1, and then the adhesive surface of the object to be sealed and its surrounding area is covered with a sealant, and the sealant is thermally cured to produce a cured sealant. When the sealing material is thermally cured, a stress acts on the sealing material to cause it to shrink. However, since the pressure-sensitive adhesive sheet is fixed to the support, the stress on the sealing material is suppressed. However, it is difficult to suppress the stress that tends to shrink in the cured sealed body obtained by separating it from the support and the adhesive sheet. Since the amount of the sealant differs between the surface side where the object to be sealed is present and the opposite surface side of the cured sealed body after separation, the shrinkage stress is likely to differ. The difference in shrinkage stress causes the cured sealed body to warp. In addition, from the viewpoint of productivity, the cured sealed body after heating is generally separated from the support and the adhesive sheet while still carrying a certain degree of heat, and therefore, even after separation, the curing of the sealing material continues and shrinkage occurs due to natural cooling, making the cured sealed body more susceptible to warping.

[0022] On the other hand, when the resin sheet of the present invention is used, a cured sealed body in which warping is effectively suppressed can be obtained for the following reasons. In other words, when an object to be sealed is placed on the surface of the thermosetting resin layer of the resin sheet of the present invention, covered with a sealing material, and the sealing material is thermally cured, the thermosetting resin layer is also thermally cured at the same time. At this time, since the thermosetting resin layer is provided on the surface side on which the object to be sealed is present, where the amount of sealing material is small and the shrinkage stress due to the curing of the sealing material is thought to be small, shrinkage stress due to the thermal curing of the thermosetting resin layer acts. As a result, it is believed that the difference in shrinkage stress between the two surfaces of the cured encapsulant can be reduced, and a cured encapsulant in which warping is effectively suppressed can be obtained.

[0023] In addition, the thermosetting resin layer, which contributes to suppressing warping of the cured sealed body, can be thermally cured to form a cured resin layer, which functions as a protective film. In other words, by using the resin sheet of the present invention and undergoing the above-mentioned sealing process, a cured resin layer can be formed on one surface of the cured sealed body at the same time, so that the process for forming the cured resin layer can be omitted, which also contributes to improving productivity.

[0024] Hereinafter, each layer of the resin sheet according to one embodiment of the present invention will be described.

[0025] <Thermosetting resin layer> The resin sheet of the present invention has a thermosetting resin layer formed from a thermosetting resin composition containing a polymerizable component (A) and a thermosetting component (B). The thermosetting resin layer is thermally cured together with the sealing material when the sealing material is thermally cured, thereby reducing the difference in shrinkage stress between the two surfaces of the cured sealed body and contributing to suppressing warping that may occur in the resulting cured sealed body. The thermosetting resin layer is thermally cured to become a cured resin layer. The cured resin layer is formed on one surface of the resulting cured sealed body and functions as a protective film.

[0026] From the viewpoint of obtaining a resin sheet capable of producing a cured sealed body having a flat surface while suppressing warping, the storage modulus E' at 23°C of the cured resin layer obtained by thermally curing the thermosetting resin layer is preferably 1.0 × 107 Pa or more, more preferably 1.0×10 8 Pa or more, more preferably 1.0×10 9 Pa or more, and even more preferably 5.0×10 9 Pa or more, and preferably 1.0×10 13 Pa or less, more preferably 1.0×10 12 Pa or less, more preferably 5.0×10 11 Pa or less, and even more preferably 1.0×10 11 Pa or less. In this specification, the storage modulus E' refers to a value measured based on the method described in the Examples.

[0027] Since the objects to be sealed are placed on the surface of the thermosetting resin layer, it is preferable that the surface of the thermosetting resin layer has adhesiveness in order to improve adhesion with the objects to be sealed. In addition, it is preferable that the surface of the thermosetting resin layer opposite the side on which the object to be sealed is placed also has adhesiveness from the viewpoints of improving adhesion to a support or the like, and, in the case of a resin sheet provided with a substrate, improving adhesion to the substrate.

[0028] The adhesive strength on the surface of the thermosetting resin layer at room temperature (23° C.) is preferably 0.01 to 5 N / 25 mm, more preferably 0.05 to 4 N / 25 mm, and even more preferably 0.1 to 3 N / 25 mm. In this specification, the adhesive strength on the surface of the thermosetting resin layer refers to a value measured by the method described in the examples.

[0029] In the resin sheet of one embodiment of the present invention, the thickness of the thermosetting resin layer is preferably 1 to 500 μm, more preferably 5 to 300 μm, even more preferably 10 to 200 μm, and even more preferably 15 to 100 μm.

[0030] In the present invention, the thermosetting resin layer is a layer formed from a thermosetting resin composition containing a polymer component (A) and a thermosetting component (B). However, the thermosetting resin composition may further contain one or more selected from a colorant (C), a coupling agent (D), and an inorganic filler (E). From the viewpoint of obtaining a resin sheet that can be used to produce a cured sealed body having a flat surface while suppressing warping, it is preferable that the thermosetting resin composition contains at least an inorganic filler (E).

[0031] (Polymer component (A)) The polymer component (A) contained in the thermosetting resin composition means a compound having a mass average molecular weight of 20,000 or more and having at least one type of repeating unit. By containing the polymerizable component (A), the thermosetting resin composition can impart flexibility and film-forming properties to the formed thermosetting resin layer, thereby making it possible to improve the sheet property retention. The mass average molecular weight (Mw) of the polymer component (A) is preferably 20,000 or more, more preferably 20,000 to 3,000,000, even more preferably 50,000 to 2,000,000, still more preferably 100,000 to 1,500,000, and even more preferably 200,000 to 1,000,000.

[0032] The content of the polymer component (A) is preferably 5 to 50 mass %, more preferably 8 to 40 mass %, and further preferably 10 to 30 mass %, based on the total amount (100 mass %) of the active ingredients of the thermosetting resin composition.

[0033] Examples of the polymer component (A) include acrylic polymers, polyesters, phenoxy resins, polycarbonates, polyethers, polyurethanes, polysiloxanes, and rubber polymers. These polymer components (A) may be used alone or in combination of two or more kinds. In this specification, although an acrylic polymer having an epoxy group and a phenoxy resin having an epoxy group are thermosetting, they are included in the concept of polymer component (A) as long as they have a mass average molecular weight of 20,000 or more and have at least one type of repeating unit.

[0034] Of these, the polymer component (A) preferably contains an acrylic polymer (A1). The content of the acrylic polymer (A1) in the polymer component (A) is preferably 60 to 100 mass%, more preferably 70 to 100 mass%, even more preferably 80 to 100 mass%, and still more preferably 90 to 100 mass%, based on the total amount (100 mass%) of the polymer component (A) contained in the thermosetting resin composition.

[0035] (Acrylic polymer (A1)) The mass average molecular weight (Mw) of the acrylic polymer (A1) is preferably from 20,000 to 3,000,000, more preferably from 100,000 to 1,500,000, even more preferably from 150,000 to 1,200,000, and still more preferably from 250,000 to 1,000,000, from the viewpoint of imparting flexibility and film-forming properties to the thermosetting resin layer to be formed.

[0036] The glass transition temperature (Tg) of the acrylic polymer (A1) is preferably −60 to 50° C., more preferably −50 to 30° C., even more preferably −40 to 10° C., and still more preferably −35 to 5° C., from the viewpoint of imparting good adhesiveness to the surface of the thermosetting resin layer to be formed and from the viewpoint of improving the reliability of a cured sealed body with a cured resin layer produced using the resin sheet.

[0037] The acrylic polymer (A1) may be a polymer containing an alkyl (meth)acrylate as a main component. Specifically, an acrylic polymer containing a structural unit (a1) derived from an alkyl (meth)acrylate (a1') having an alkyl group having 1 to 18 carbon atoms (hereinafter also referred to as "monomer (a1')") is preferred, and an acrylic copolymer containing, together with the structural unit (a1), a structural unit (a2) derived from a functional group-containing monomer (a2') (hereinafter also referred to as "monomer (a2')") is more preferred. The acrylic polymer (A1) may be used alone or in combination of two or more kinds. When the acrylic polymer (A1) is a copolymer, the copolymer may be in the form of a block copolymer, a random copolymer, an alternating copolymer or a graft copolymer.

[0038] From the viewpoint of imparting flexibility and film-forming properties to the formed thermosetting resin layer, the number of carbon atoms in the alkyl group of the monomer (a1') is preferably 1 to 18, more preferably 1 to 12, and further preferably 1 to 8. The alkyl group may be a linear alkyl group or a branched alkyl group. These monomers (a1') may be used alone or in combination of two or more kinds.

[0039] From the viewpoint of improving the reliability of a cured sealed body with a cured resin layer produced using the resin sheet, the monomer (a1') preferably contains an alkyl(meth)acrylate having an alkyl group having 1 to 3 carbon atoms, and more preferably contains methyl(meth)acrylate. From the above viewpoints, the content of the structural unit (a11) derived from an alkyl (meth)acrylate having an alkyl group having 1 to 3 carbon atoms is preferably 1 to 80 mass%, more preferably 5 to 80 mass%, and even more preferably 10 to 80 mass%, relative to all structural units (100 mass%) of the acrylic polymer (A1).

[0040] Furthermore, from the viewpoint of increasing the gloss value of the cured resin layer obtained by thermally curing the formed thermosetting resin layer and improving suitability for laser marking, it is preferable that the monomer (a1') contains an alkyl (meth)acrylate having an alkyl group having 4 or more carbon atoms, more preferably an alkyl (meth)acrylate having an alkyl group having 4 to 6 carbon atoms, and even more preferably butyl (meth)acrylate. From the above viewpoints, the content of the structural unit (a12) derived from an alkyl (meth)acrylate having an alkyl group having 4 or more carbon atoms (preferably 4 to 6, and more preferably 4) is preferably 1 to 70 mass%, more preferably 5 to 65 mass%, and even more preferably 10 to 60 mass%, relative to all structural units (100 mass%) of the acrylic polymer (A1).

[0041] The content of the structural unit (a1) is preferably 50% by mass or more, more preferably 50 to 99% by mass, even more preferably 55 to 90% by mass, and still more preferably 60 to 90% by mass, based on all structural units (100% by mass) of the acrylic polymer (A1).

[0042] The monomer (a2') is preferably at least one selected from the group consisting of hydroxy group-containing monomers and epoxy group-containing monomers. The monomer (a2') may be used alone or in combination of two or more kinds.

[0043] Examples of hydroxy group-containing monomers include hydroxyalkyl (meth)acrylates such as 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 unsaturated alcohols such as vinyl alcohol and allyl alcohol. Among these, the hydroxy group-containing monomer is preferably a hydroxyalkyl (meth)acrylate, and more preferably 2-hydroxyethyl (meth)acrylate.

[0044] Examples of epoxy-containing monomers include epoxy group-containing (meth)acrylates such as glycidyl (meth)acrylate, β-methylglycidyl (meth)acrylate, (3,4-epoxycyclohexyl)methyl (meth)acrylate, and 3-epoxycyclo-2-hydroxypropyl (meth)acrylate; glycidyl crotonate, and allyl glycidyl ether. Among these, the epoxy-containing monomer is preferably an epoxy group-containing (meth)acrylate, and more preferably glycidyl (meth)acrylate.

[0045] The content of the structural unit (a2) is preferably 1 to 50 mass%, more preferably 5 to 45 mass%, even more preferably 10 to 40 mass%, and still more preferably 10 to 30 mass%, based on all structural units (100 mass%) of the acrylic polymer (A1).

[0046] The acrylic polymer (A1) may contain structural units derived from monomers other than the above structural units (a1) and (a2), provided the effects of the present invention are not impaired. Examples of the other monomers include vinyl acetate, styrene, ethylene, and α-olefins.

[0047] <Thermosetting component (B)> The thermosetting component (B) serves to thermally cure the formed thermosetting resin layer to form a hard cured resin layer, and is a compound having a mass average molecular weight of less than 20,000. The mass average molecular weight (Mw) of the curable component (B) is preferably 10,000 or less, and more preferably 100 to 10,000.

[0048] From the viewpoint of producing a resin sheet capable of suppressing warping and producing a cured sealed body having a flat surface, the thermosetting component (B) preferably contains an epoxy compound (B1), which is a compound having an epoxy group, and a thermosetting agent (B2), and more preferably contains a curing accelerator (B3) in addition to the epoxy compound (B1) and the thermosetting agent (B2).

[0049] Examples of the epoxy compound (B1) include polyfunctional epoxy resins, bisphenol A diglycidyl ether and hydrogenated products thereof, 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, which have two or more functional groups in the molecule and have a mass average molecular weight of less than 20,000. The epoxy compound (B1) may be used alone or in combination of two or more kinds.

[0050] From the viewpoint of obtaining a resin sheet capable of producing a cured sealed product having a flat surface with suppressed warping, the content of the epoxy compound (B1) is preferably 1 to 500 parts by mass, more preferably 3 to 300 parts by mass, even more preferably 10 to 150 parts by mass, and still more preferably 20 to 120 parts by mass relative to 100 parts by mass of the polymer component (A) contained in the thermosetting resin composition.

[0051] The heat curing agent (B2) functions as a curing agent for the epoxy compound (B1). The heat curing agent (B2) is preferably a compound having two or more functional groups capable of reacting with an epoxy group in one molecule. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group, an acid anhydride, etc. Among these, from the viewpoint of obtaining an adhesive laminate capable of producing a cured sealed body with a cured resin film having a flat surface while suppressing warping, a phenolic hydroxyl group, an amino group, or an acid anhydride is preferred, a phenolic hydroxyl group or an amino group is more preferred, and an amino group is even more preferred.

[0052] Examples of phenolic thermosetting agents having a phenol group include polyfunctional phenolic resins, biphenols, novolac-type phenolic resins, dicyclopentadiene-type phenolic resins, xylok-type phenolic resins, and aralkyl phenolic resins. An example of an amine-based heat curing agent having an amino group is dicyandiamide (DICY). These heat curing agents (B2) may be used alone or in combination of two or more kinds.

[0053] The content of the thermosetting agent (B2) is preferably 0.1 to 500 parts by mass, more preferably 1 to 200 parts by mass, based on 100 parts by mass of the epoxy compound (B1), from the viewpoint of obtaining an adhesive laminate that can produce a cured sealed article with a cured resin film having a flat surface while suppressing warping.

[0054] The curing accelerator (B3) is a compound that has the function of increasing the rate of thermal curing when the thermosetting resin layer to be formed is thermally cured. Examples of the curing accelerator (B3) include tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol; imidazoles such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, and 2-phenyl-4-methyl-5-hydroxymethylimidazole; organic phosphines such as tributylphosphine, diphenylphosphine, and triphenylphosphine; and tetraphenylboron salts such as tetraphenylphosphonium tetraphenylborate and triphenylphosphine tetraphenylborate. These curing accelerators (B3) may be used alone or in combination of two or more kinds.

[0055] From the viewpoint of obtaining a resin sheet capable of suppressing warping and producing a cured sealed product having a flat surface, the content of the curing accelerator (B3) is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 6 parts by mass, and even more preferably 0.3 to 4 parts by mass relative to 100 parts by mass of the total amount of the epoxy compound (B1) and the thermosetting agent (B2).

[0056] <Colorant (C)> The thermosetting resin composition used in one embodiment of the present invention may further contain a colorant (C). The thermosetting resin layer formed from the thermosetting resin composition containing the colorant (C) can, when thermally cured to form a cured resin layer, block infrared rays and the like generated from surrounding devices and prevent malfunction of the object to be sealed (such as a semiconductor chip).

[0057] As colorants (C) organic or inorganic pigments and dyes can be used. As the dye, any dye such as an acid dye, a reactive dye, a direct dye, a disperse dye, or a cationic dye can be used. The pigment is not particularly limited, and may be appropriately selected from known pigments. Among these, black pigments are preferred from the viewpoints of providing good electromagnetic wave and infrared shielding properties and further improving identifiability by laser marking. Examples of black pigments include carbon black, iron oxide, manganese dioxide, aniline black, and activated carbon. From the viewpoint of improving the reliability of the semiconductor chip, carbon black is preferred. These colorants (C) may be used alone or in combination of two or more kinds.

[0058] However, in the thermosetting resin composition used in one embodiment of the present invention, the content of the colorant (C) is preferably less than 8 mass % relative to the total amount (100 mass %) of the active ingredients of the thermosetting resin composition. If the content of the colorant (C) is less than 8% by mass, a resin sheet can be obtained in which the presence or absence of cracks on the surface of the chips and chipping can be visually confirmed. From the above viewpoints, in the thermosetting resin composition used in one embodiment of the present invention, the content of the colorant (C) is preferably less than 5 mass%, more preferably less than 2 mass%, even more preferably less than 1 mass%, and still more preferably less than 0.5 mass%, relative to the total amount (100 mass%) of the active ingredients of the thermosetting resin composition.

[0059] From the viewpoint of allowing the cured resin layer obtained by thermally curing the formed thermosetting resin layer to exhibit an effect of shielding infrared rays and the like, the content of the colorant (C) is preferably 0.01 mass % or more, more preferably 0.05 mass % or more, even more preferably 0.10 mass % or more, and still more preferably 0.15 mass % or more, relative to the total amount (100 mass %) of the active ingredients of the thermosetting resin composition.

[0060] <Coupling agent (D)> The thermosetting resin composition used in one embodiment of the present invention may further contain a coupling agent (D). The thermosetting resin layer formed from the thermosetting resin composition containing the coupling agent (D) can improve the adhesion to the object to be sealed when the object to be sealed is placed on the thermosetting resin layer. In addition, the cured resin layer obtained by thermally curing the thermosetting resin layer can improve water resistance without impairing heat resistance.

[0061] The coupling agent (D) is preferably a compound that reacts with the functional groups of the polymerizable component (A) and the thermosetting component (B), and specifically, a silane coupling agent is preferred. Examples of silane coupling agents include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-(methacryloxypropyl)trimethoxysilane, 3-aminopropyltrimethoxysilane, N-6-(aminoethyl)-3-aminopropyltrimethoxysilane, N-6-(aminoethyl)-3-aminopropylmethyldiethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, bis(3-triethoxysilylpropyl)tetrasulfane, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, and imidazole silane. These coupling agents (D) may be used alone or in combination of two or more kinds.

[0062] The molecular weight of the coupling agent (D) is preferably 100 to 15,000, more preferably 125 to 10,000, more preferably 150 to 5,000, even more preferably 175 to 3,000, and still more preferably 200 to 2,000.

[0063] The content of the coupling agent (D) is preferably 0.01 to 10 mass%, more preferably 0.05 to 7 mass%, even more preferably 0.10 to 4 mass%, and still more preferably 0.15 to 2 mass%, relative to the total amount (100 mass%) of the active ingredients of the thermosetting resin composition.

[0064] <Inorganic filler (E)> From the viewpoint of obtaining a resin sheet that is suppressed in warping and enables the production of a cured sealed product having a flat surface, it is preferable that the thermosetting resin composition used in one embodiment of the present invention further contains an inorganic filler (E). By forming the thermosetting resin layer from a thermosetting resin composition containing an inorganic filler (E), the degree of thermal curing of the thermosetting resin layer can be adjusted so that the difference in shrinkage stress between the two surfaces of the cured sealed body is reduced when the sealing material is thermally cured. As a result, it is possible to produce a cured sealed body having a flat surface while suppressing warping. In addition, the thermal expansion coefficient of the cured resin layer obtained by thermally curing the formed thermosetting resin layer can be adjusted to an appropriate range, thereby improving the reliability of the object to be sealed and reducing the moisture absorption rate of the cured resin layer.

[0065] Examples of the inorganic filler (E) include powders of silica, alumina, talc, calcium carbonate, titanium oxide, iron oxide, silicon carbide, boron nitride, etc., beads obtained by spheronizing these powders, single crystal fibers, glass fibers, and other non-thermally expandable particles. These inorganic fillers (E) may be used alone or in combination of two or more kinds. Among these, silica or alumina is preferred from the viewpoint of obtaining a resin sheet that can suppress warping and produce a cured encapsulant having a flat surface.

[0066] The average particle size of the inorganic filler (E) is preferably 0.3 to 50 μm, more preferably 0.5 to 30 μm, and even more preferably 0.7 to 10 μm, from the viewpoint of improving the gloss value of the cured resin film obtained by thermally curing the formed thermosetting resin layer.

[0067] From the viewpoint of obtaining a resin sheet capable of producing a cured sealed body having a flat surface with suppressed warping, the content of the inorganic filler (E) is preferably 25 to 80 mass %, more preferably 30 to 70 mass %, even more preferably 40 to 65 mass %, and still more preferably 45 to 60 mass %, relative to the total amount (100 mass %) of the active ingredients of the thermosetting resin composition.

[0068] <Other additives> The thermosetting resin composition used in one embodiment of the present invention may further contain additives other than the above-mentioned polymerizable component (A), thermosetting component (B), colorant (C), coupling agent (D) and inorganic filler (E) (hereinafter referred to as components (A) to (E)) within a range that does not impair the effects of the present invention. Examples of additives other than the components (A) to (E) include crosslinking agents, leveling agents, plasticizers, antistatic agents, antioxidants, ion scavengers, gettering agents, and chain transfer agents. The total content of additives other than components (A) to (E) is preferably 0 to 20 mass%, more preferably 0 to 10 mass%, and even more preferably 0 to 5 mass%, relative to the total amount (100 mass%) of active ingredients in the thermosetting resin composition.

[0069] <Base material> The resin sheet according to one embodiment of the present invention may have a substrate together with the thermosetting resin layer. The thickness of the substrate used in one embodiment of the present invention is preferably 10 to 500 μm, more preferably 15 to 300 μm, and further preferably 20 to 200 μm.

[0070] The substrate used in one embodiment of the present invention may be, for example, a sheet-like material made of one or more materials selected from paper, resin, metal, etc., with a resin substrate containing a resin being preferred. Examples of paper materials include thin paper, medium-quality paper, fine paper, impregnated paper, coated paper, art paper, parchment paper, and glassine paper. Examples of resins that constitute the resin substrate include polyolefin resins such as polyethylene and polypropylene; vinyl resins such as polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl acetate copolymer, and ethylene-vinyl alcohol copolymer; polyester resins such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polystyrene; acrylonitrile-butadiene-styrene copolymer; cellulose triacetate; polycarbonate; urethane resins such as polyurethane and acrylic-modified polyurethane; polymethylpentene; polysulfone; polyether ether ketone; polyether sulfone; polyphenylene sulfide; polyimide resins such as polyetherimide and polyimide; polyamide resins; acrylic resins; and fluorine-based resins. Examples of metals include aluminum, tin, chromium, and titanium.

[0071] The resin substrate may contain, in addition to the above-mentioned resin, additives for substrates such as ultraviolet absorbers, light stabilizers, antioxidants, antistatic agents, slip agents, antiblocking agents, colorants, and the like.

[0072] The substrate used in the present invention may be formed from one type of material, or may be formed from two or more types of materials. Examples of substrates formed from two or more materials include paper laminated with a thermoplastic resin such as polyethylene, and resin substrates containing resin with a metal film formed on the surface. Examples of methods for forming the metal layer include a method of depositing the above-mentioned metal by a PVD method such as vacuum deposition, sputtering, or ion plating, or a method of attaching a metal foil made of the above-mentioned metal using a general adhesive.

[0073] Furthermore, in the case of a structure in which a thermosetting resin layer is laminated on a substrate, such as the resin sheet 1a shown in FIG. 1(a), in order to improve the adhesion between the substrate and the thermosetting resin layer, the surface of the substrate may be subjected to a surface treatment such as an oxidation method or a roughening method, an easy-adhesion treatment, or a primer treatment.

[0074] <Adhesive layer> The resin sheet of one embodiment of the present invention may further include a pressure-sensitive adhesive layer. In one embodiment of the present invention, the adhesive strength of the adhesive layer is preferably 0.10 to 10.0 N / 25 mm, more preferably 0.15 to 8.0 N / 25 mm, even more preferably 0.20 to 6.0 N / 25 mm, and still more preferably 0.25 to 4.0 N / 25 mm. In this specification, the adhesive strength refers to a value measured by the method described in the Examples section. Furthermore, for example, when the resin sheet has a first pressure-sensitive adhesive layer and a second pressure-sensitive adhesive layer, like the resin sheet 1d shown in FIG. 1(d), it is preferable that the adhesive strength of each of the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer is within the above range.

[0075] In one embodiment of the present invention, the thickness of the pressure-sensitive adhesive layer is preferably 1 to 100 μm, more preferably 3 to 50 μm, and even more preferably 5 to 25 μm.

[0076] The pressure-sensitive adhesive layer can be formed from a pressure-sensitive adhesive composition containing a pressure-sensitive adhesive resin. The adhesive resin used in one embodiment of the present invention may be a polymer that has adhesiveness by itself and has a mass average molecular weight (Mw) of 10,000 or more. Examples of the adhesive resin include rubber-based resins such as acrylic resins, urethane resins, and polyisobutylene resins, polyester resins, olefin resins, silicone resins, and polyvinyl ether resins. These adhesive resins may be used alone or in combination of two or more kinds.

[0077] The mass average molecular weight (Mw) of the adhesive resin used in one embodiment of the present invention is preferably from 10,000 to 2,000,000, more preferably from 20,000 to 1,500,000, and even more preferably from 30,000 to 1,000,000, from the viewpoint of improving adhesive strength.

[0078] The pressure-sensitive adhesive composition may further contain a pressure-sensitive adhesive additive depending on the type of pressure-sensitive adhesive resin used. Examples of such adhesive additives include crosslinkers, tackifiers, polymerizable compounds, polymerization initiators, antioxidants, softeners (plasticizers), rust inhibitors, pigments, dyes, retarders, reaction accelerators (catalysts), ultraviolet absorbers, and antistatic agents.

[0079] The content of the adhesive resin is preferably 35% by mass or more, more preferably 50% by mass or more, even more preferably 60% by mass or more, and even more preferably 70% by mass or more, based on the total amount (100% by mass) of the active ingredients of the adhesive composition.

[0080] The adhesive layer of a resin sheet having a configuration such as that of the resin sheets 1b, 1c, and 1d in FIG. 1 may be a layer formed from an energy ray-curable adhesive composition containing an energy ray-curable adhesive resin and a photopolymerization initiator. By forming an adhesive layer from such an energy ray-curable adhesive composition, after forming the cured resin layer and the cured sealing body, the adhesive strength can be reduced by irradiating with energy rays, making it possible to easily separate the adhesive layer from the cured resin layer. Examples of the energy beam include ultraviolet rays and electron beams, with ultraviolet rays being preferred.

[0081] The energy ray-curable adhesive composition may be a composition containing an energy ray-curable adhesive resin having a polymerizable functional group such as a (meth)acryloyl group or a vinyl group introduced into the side chain of the above-mentioned adhesive resin, or may be a composition containing a monomer or oligomer having a polymerizable functional group. These compositions preferably further contain a photopolymerization initiator.

[0082] Examples of the photopolymerization initiator include 1-hydroxycyclohexylphenyl ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzyl phenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyrolnitrile, dibenzyl, diacetyl, and 8-chloroanthraquinone. These photopolymerization initiators may be used alone or in combination of two or more kinds. The content of the photopolymerization initiator is preferably 0.01 to 10 parts by mass, more preferably 0.03 to 5 parts by mass, and even more preferably 0.05 to 2 parts by mass, relative to 100 parts by mass of the energy ray-curable adhesive resin or 100 parts by mass of the monomer or oligomer having a polymerizable functional group.

[0083] [Method of using the adhesive laminate] By using the resin sheet of the present invention in the production of a cured sealed article, a cured sealed article having a flat surface with reduced warping can be produced with improved productivity. Therefore, the present invention can also provide a method for using a resin sheet as shown in [I] below. [I] A method for using the resin sheet of the present invention, placing an object to be sealed on the surface of the thermosetting resin layer; covering the object to be sealed and at least a surface of the thermosetting resin layer in a peripheral portion of the object to be sealed with a sealing material; A method of using a resin sheet, comprising thermally curing the sealing material to form a cured sealed body including the object to be sealed.

[0084] In the method of use described in [I] above, it is preferable that when the sealing material is thermally cured, the thermosetting resin layer is also thermally cured to form a cured resin layer, thereby forming a cured sealed body with a thermosetting resin layer. By using the resin sheet of the present invention described above, it is possible to produce a cured sealed product (cured sealed product with a cured resin film) having a flat surface with reduced warping with improved productivity. In the method of use described in [I] above, the preferred configuration of the resin sheet is as described above, and the type of encapsulant, the coating method of the encapsulant, the conditions for thermal curing, etc. are as described in the section below titled "Method for producing cured encapsulated body with cured resin layer."

[0085] [Method for producing a cured sealed body with a cured resin film] An example of a method for producing a cured sealed body with a cured resin film using the resin sheet of the present invention includes a method having the following steps (i) to (iii). Step (i): A step of placing an object to be sealed on a part of the surface of the thermosetting resin layer of the resin sheet. Step (ii): A step of covering the object to be sealed and at least the surface of the thermosetting resin layer in the periphery of the object to be sealed with a sealing material. Step (iii): A step of thermally curing the sealing material to form a cured sealed body including the object to be sealed, and also thermally curing the thermosetting resin layer to form a cured resin layer, thereby obtaining a cured sealed body with a cured resin layer. Fig. 2 is a schematic cross-sectional view showing a process for producing a cured sealed body with a cured resin layer using the resin sheet 1d shown in Fig. 1(d). Each of the above steps will be described below with reference to Fig. 2 as appropriate.

[0086] <Process (i)> Step (i) is a step of placing an object to be sealed on a part of the surface of the thermosetting resin layer of the resin sheet. FIG. 2(a) shows a state in which the adhesive surface of the second adhesive layer 32 of the resin sheet 1d is attached to a support 100, and an object to be sealed 60 is placed on part of the surface of the thermosetting resin layer . Although FIG. 2(a) shows an example in which the resin sheet 1d shown in FIG. 1(d) is used, even when a resin sheet of the present invention having a different configuration is used, the support, the resin sheet, and the object to be sealed are laminated or placed in this order as shown in FIG. 2(a).

[0087] Incidentally, the step (i) is preferably carried out at a temperature at which the thermosetting resin layer is not thermally cured. The specific temperature condition for the step (i) is usually 10 to 80°C.

[0088] In addition, when using a resin sheet having a second adhesive layer on the support side, such as the resin sheet 1d in Figure 1 (d), it is preferable that the entire adhesive surface of the second adhesive layer of the resin sheet is attached to the support. Therefore, the support is preferably in the form of a plate. In this case, the area of ​​the adhesive surface of the second adhesive layer and the surface of the backing to which it is attached is preferably equal to or larger than the area of ​​the adhesive surface of the second adhesive layer, as shown in FIG.

[0089] The material constituting the support is appropriately selected in consideration of the required properties such as mechanical strength and heat resistance depending on the type of object to be sealed and the type of sealing material used in step (ii). Specific examples of materials constituting the support include metal materials such as SUS; non-metallic inorganic materials such as glass and silicon wafers; resin materials such as epoxy resin, ABS resin, acrylic resin, engineering plastic, super engineering plastic, polyimide resin, and polyamideimide resin; and composite materials such as glass epoxy resin. Of these, SUS, glass, and silicon wafers are preferred. Examples of engineering plastics include nylon, polycarbonate (PC), and polyethylene terephthalate (PET). Examples of super engineering plastics include polyphenylene sulfide (PPS), polyethersulfone (PES), and polyetheretherketone (PEEK).

[0090] The thickness of the support is appropriately selected depending on the type of object to be sealed and the type of sealing material used in step (ii), but is preferably 20 μm or more and 50 mm or less, and more preferably 60 μm or more and 20 mm or less.

[0091] On the other hand, examples of objects to be sealed that are placed on part of the surface of the thermosetting resin layer include semiconductor chips, semiconductor wafers, compound semiconductors, semiconductor packages, electronic components, sapphire substrates, displays, and panel substrates.

[0092] For example, when the object to be encapsulated is a semiconductor chip, the resin sheet of the present invention can be used to manufacture a semiconductor chip with a cured resin layer. The semiconductor chip may be any known one, and an integrated circuit composed of circuit elements such as transistors, resistors, and capacitors is formed on the circuit surface of the semiconductor chip. The semiconductor chip is preferably placed so that the back surface opposite to the circuit surface is covered with the surface of the thermosetting resin layer, in which case the circuit surface of the semiconductor chip is exposed after placement. For mounting the semiconductor chip, a known device such as a flip chip bonder or a die bonder can be used. The layout of the semiconductor chips, the number of chips to be arranged, etc. may be appropriately determined depending on the desired package form, production volume, etc.

[0093] Here, it is preferable to apply this to packages such as FOWLP, FOPLP, etc., in which an area of ​​a semiconductor chip larger than the chip size is covered with an encapsulant, and a rewiring layer is formed not only on the circuit surface of the semiconductor chip but also on the surface area of ​​the encapsulant. Therefore, the semiconductor chip is placed on a portion of the surface of the thermosetting resin layer, and it is preferable that a plurality of semiconductor chips are placed on the surface in a state aligned at regular intervals, and it is even more preferable that a plurality of semiconductor chips are placed on the surface in a state aligned in a matrix of multiple rows and multiple columns in a state aligned at regular intervals. The distance between the semiconductor chips may be appropriately determined depending on the desired package shape and other factors.

[0094] <Process (ii)> Step (ii) is a step of covering the object to be sealed and at least the surface of the thermosetting resin layer in the periphery of the object to be sealed with a sealing material. The sealing material covers the entire exposed surface of the object to be sealed, and also fills the gaps between the multiple semiconductor chips. FIG. 2(b) shows a state in which the object to be sealed 60 and the surface of the thermosetting resin layer 10 are covered with a sealing material 70 so as to entirely cover the surface. In this process, as shown in FIG. 2(b), the thermosetting resin layer 10 may be coated with the sealing material 70 so as to cover the entire surface of the thermosetting resin layer 10, or only a portion of the surface of the thermosetting resin layer 10 that constitutes the periphery of the object to be sealed 60 may be coated with the sealing material 70.

[0095] The sealing material has the function of protecting the object to be sealed and the elements associated therewith from the external environment. The sealing material used in the manufacturing method of the present invention is a thermosetting sealing material containing a thermosetting resin. In addition, the encapsulating material may be in a solid form such as granules, pellets, or a film at room temperature, or may be in a liquid form in the form of a composition. From the viewpoint of workability, however, a film-like encapsulating material, that is, an encapsulating resin film, is preferred.

[0096] The coating method can be appropriately selected from methods applied in conventional sealing processes according to the type of sealing material, and for example, roll lamination, vacuum pressing, vacuum lamination, spin coating, die coating, transfer molding, compression molding, etc. can be applied.

[0097] <Step (iii)> Step (iii) is a step of thermally curing the sealing material to form a cured sealed body including the object to be sealed, and also thermally curing the thermosetting resin layer to form a cured resin layer, thereby obtaining a cured sealed body with a cured resin layer. The step (iii) may be carried out separately from the preceding step (ii) or simultaneously. For example, when the sealing material is heated in the previous step (ii), this step may also be performed by heating, and the sealing material may be thermally cured in that state.

[0098] As shown in FIG. 2( c ), in this step, the sealing material is thermally cured to form a cured sealing body 71 including the object to be sealed 60, and the thermosetting resin layer is also thermally cured to form a cured resin layer 11. In this process, the thermosetting resin layer is thermally cured along with the sealing material, so that the difference in shrinkage stress between the two surfaces of the cured sealed body can be reduced, and it is believed that warping of the cured sealed body can be effectively suppressed.

[0099] The temperature condition in step (iii) may be any temperature condition that is equal to or higher than the temperature at which the sealing material and the thermosetting resin layer are thermally cured, and is set appropriately depending on the type of sealing material and the types of components constituting the thermosetting resin layer, but is usually 120 to 220°C.

[0100] Thereafter, as shown in FIG. 2(d), the cured resin layer formed by thermal curing of the thermosetting resin layer is separated at the interface between the first adhesive layer 31 and a cured sealed body 80 with a cured resin layer, which has the cured resin layer 11 and a cured sealed body 71 including the object to be sealed 60, can be obtained. Here, when the first pressure-sensitive adhesive layer 31 is a layer formed from an energy ray-curable pressure-sensitive adhesive composition, it can be easily separated by irradiating it with energy rays.

[0101] In addition, when a general adhesive sheet is used, warping may occur in the cured sealed body after separation from the support. However, the cured sealed body with a cured resin layer obtained using the resin sheet of the present invention has a cured resin layer, and therefore, warping that may occur in the cured sealed body can be effectively suppressed.

[0102] The cured sealed body with the cured resin layer thus obtained may then be subjected to a process of grinding the cured sealed body until the circuit surface of the semiconductor chip is exposed and rewiring the circuit surface, a process of forming external electrode pads and connecting the external electrode pads to external terminal electrodes, etc. Furthermore, after external terminal electrodes are connected to the cured sealing body, the cured sealing body can be divided into individual pieces to manufacture semiconductor devices. EXAMPLES

[0103] The present invention will be described in detail with reference to the following examples, but the present invention is not limited to the following examples. Note that the physical properties in the following Production Examples and Examples were measured by the following methods.

[0104] <Mass average molecular weight (Mw)> Measurements were carried out using a gel permeation chromatograph (manufactured by Tosoh Corporation, product name "HLC-8020") under the conditions below, and values ​​measured in terms of standard polystyrene were used. (Measurement conditions) Column: "TSK guard column HXL-L", "TSK gel G2500HXL", "TSK gel G2000HXL", and "TSK gel G1000HXL" (all manufactured by Tosoh Corporation) connected in series Column temperature: 40℃ Developing solvent: Tetrahydrofuran ·Flow rate: 1.0mL / min

[0105] <Measurement of thickness of each layer> The measurements were performed using a constant pressure thickness gauge manufactured by Tecrock Corporation (model number: "PG-02J", standard specifications: compliant with JIS K6783, Z1702, Z1709).

[0106] <Storage modulus E' of cured resin layer after thermal curing of thermosetting resin layer> After laminating the thermosetting resin layer to a thickness of 200 μm, the laminate was placed in an oven in an air atmosphere and heated at 130° C. for 2 hours to thermally cure the 200 μm-thick thermosetting resin layer to form a cured resin layer. Using a dynamic viscoelasticity measuring device (manufactured by TA Instruments, product name "DMAQ800"), the storage modulus E' of the formed cured resin layer at 23°C was measured under the conditions of a test start temperature of 0°C, a test end temperature of 300°C, a heating rate of 3°C / min, a vibration frequency of 11 Hz, and an amplitude of 20 μm.

[0107] <Adhesive strength measurement> A 50 μm-thick PET film (manufactured by Toyobo Co., Ltd., product name "Cosmoshine A4100") was laminated on the surface of the pressure-sensitive adhesive layer or thermosetting resin layer formed on the release film. The release film was then removed, and the exposed surface of the adhesive layer or thermosetting resin layer was attached to a stainless steel plate (SUS304 #360 polished) as an adherend, and left to stand for 24 hours in an environment of 23°C and 50% RH (relative humidity). After that, in the same environment, the adhesive strength was measured at 23°C using the 180° peel method at a pulling speed of 300 mm / min based on JIS Z0237:2000.

[0108] The release materials used in the following manufacturing examples are as follows: <Removal material> Heavy release film: Manufactured by Lintec Corporation, product name "SP-PET382150", a polyethylene terephthalate (PET) film with a release layer formed from a silicone-based release agent on one side, thickness: 38 μm. Light release film: Manufactured by Lintec Corporation, product name "SP-PET381031", a release layer formed from a silicone-based release agent on one side of a PET film, thickness: 38 μm.

[0109] Manufacturing Example 1 (1) Preparation of thermosetting resin composition The components shown below in terms of type and amount (all "active ingredient ratio") were mixed, diluted with methyl ethyl ketone, and stirred uniformly to prepare a solution of a thermosetting resin composition with a solids concentration (active ingredient concentration) of 61 mass %. Acrylic polymer: amount blended = 26.07 parts by weight An acrylic polymer (mass average molecular weight: 400,000, glass transition temperature: -1°C) obtained by copolymerizing 10 parts by mass of n-butyl acrylate, 70 parts by mass of methyl acrylate, 5 parts by mass of glycidyl methacrylate, and 15 parts by mass of 2-hydroxyethyl acrylate, which corresponds to the above component (A1). Epoxy compound (1): amount blended = 10.4 parts by mass Bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation, product name "jER828", epoxy equivalent = 184 to 194 g / eq), corresponds to the above component (B1). Epoxy compound (2): amount blended = 5.2 parts by weight Dicyclopentadiene type epoxy resin (manufactured by DIC Corporation, product name "Epicron HP-7200HH", epoxy equivalent = 255 to 260 g / eq), corresponds to the above component (B1). Epoxy compound (3): amount blended = 1.7 parts by weight Bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation, product name "jER1055", epoxy equivalent = 800 to 900 g / eq), corresponds to the above component (B1). Heat curing agent: amount blended = 0.42 parts by weight Dicyandiamide (manufactured by ADEKA Corporation, product name "ADEKA Hardener EH-3636AS", active hydrogen content = 21g / eq), equivalent to the above component (B2). Curing accelerator: amount blended = 0.42 parts by weight 2-Phenyl-4,5-dihydroxymethylimidazole (manufactured by Shikoku Chemical Industry Co., Ltd., product name "Curezol 2PHZ"), which corresponds to the above component (B3). Colorant: amount blended = 0.20 parts by weight Carbon black (manufactured by Mitsubishi Chemical Corporation, product name "#MA650", average particle size = 28 nm), corresponds to the above component (C). Silane coupling agent: amount blended = 0.09 parts by weight 3-Glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., product name "KBM403"), molecular weight = 236.64, corresponds to the above component (D). ·Inorganic filler: blending amount = 55.5 parts by mass Silica filler (manufactured by Admatechs, product name "SC2050MA", average particle size = 0.5 μm), corresponds to the above component (E).

[0110] (2) Formation of thermosetting resin layer The solution of the thermosetting resin composition prepared in (1) above was applied onto the release-treated surface of the light release film to form a coating film, and the coating film was dried at 120°C for 2 minutes to form a thermosetting resin layer having a thickness of 25 μm. The adhesive strength of the formed thermosetting resin layer was 0.5 N / 25 mm. The storage modulus E' of the cured resin layer obtained by thermally curing the thermosetting resin layer at 23°C is 6.5 × 10 9 It was Pa.

[0111] Manufacturing Example 2 (1) Preparation of Pressure Sensitive Adhesive Composition 100 parts by mass of the solid content of the adhesive resin, acrylic copolymer (i) shown below, was mixed with 5.0 parts by mass (solid content ratio) of isocyanate-based crosslinking agent (i) shown below, diluted with toluene, and stirred uniformly to prepare an adhesive composition with a solid content concentration (active ingredient concentration) of 25% by mass. Acrylic copolymer (i): An acrylic copolymer having a mass average molecular weight of 600,000 and having constituent units derived from raw material monomers consisting of 2-ethylhexyl acrylate (2EHA) / 2-hydroxyethyl acrylate (HEA) = 80.0 / 20.0 (mass ratio). Isocyanate crosslinking agent (i): manufactured by Tosoh Corporation, product name "Coronate L", solid content: 75% by mass.

[0112] (2) Formation of adhesive layer The adhesive composition prepared in (1) above was applied to the surface of the release agent layer of the light release film to form a coating film, and the coating film was dried at 100°C for 60 seconds to form a first adhesive layer having a thickness of 5 μm. Similarly, a second pressure-sensitive adhesive layer having a thickness of 5 μm was formed on the surface of the release agent layer of the above-mentioned heavy release film. The adhesive strength of each of the first and second pressure-sensitive adhesive layers, measured according to the above method, was 0.3 N / 25 mm.

[0113] Example 1 The first and second pressure-sensitive adhesive layers formed in Production Example 2 were attached to both sides of a 50 μm thick polyethylene terephthalate (PET) film (manufactured by Toyobo Co., Ltd., product name "Cosmoshine A4100") serving as a substrate. Then, the light release film laminated on the first adhesive layer was removed, and the exposed adhesive surface of the first adhesive layer was bonded to the surface of the thermosetting resin layer formed in Production Example 1 to obtain a resin sheet laminated in the following order: heavy release film / second adhesive layer / substrate / first adhesive layer / thermosetting resin layer / light release film.

[0114] Example 2 A cured sealed body with a cured resin layer was produced by the following procedure. (1) Placement of semiconductor chips The heavy release film of the resin sheet produced in Example 1 was removed, and the exposed adhesive surface of the second adhesive layer was attached to a support (glass). The light release film of the resin sheet was then removed, and nine semiconductor chips (each chip size 6.4 mm x 6.4 mm, chip thickness 200 μm (#2000)) were placed on the exposed surface of the thermosetting resin layer with the required spacing so that the back surface opposite the circuit surface of each semiconductor chip was in contact with the surface.

[0115] (2) Formation of hardened sealant and hardened resin layer The nine semiconductor chips and the surface of the thermosetting resin layer at least in the peripheral portion of the semiconductor chip were covered with a thermosetting sealing resin film, which is a sealing material, and the sealing resin film was thermally cured using a vacuum heating and pressure laminator ("7024HP5" manufactured by ROHM and HAAS) to produce a cured sealed body. The sealing conditions are as follows. Preheat temperature: 100℃ for both table and diaphragm Vacuuming: 60 seconds Dynamic Press Mode: 30 seconds Static Press Mode: 10 seconds ·Sealing temperature: 180℃ Sealing time: 60 minutes In addition, together with the thermal curing of the sealing resin film, the thermosetting resin layer was also cured under the above-mentioned environment to form a cured resin layer.

[0116] (3) Separation of the cured resin layer and the first adhesive layer After the above (2), the thermosetting resin layer was thermally cured to give a cured resin layer, which was then separated at the interface between the first pressure-sensitive adhesive layer and the cured resin layer, to obtain a cured sealed body with a cured resin layer. The obtained cured sealed body with the cured resin layer was cooled to room temperature (25° C.), but no warping was observed. [Industrial Applicability]

[0117] The resin sheet of the present invention can be used to manufacture a cured sealed body including an object to be sealed, such as a semiconductor chip, by placing the object to be sealed on the surface of the thermosetting resin layer, covering it with a sealing material, and curing it. In addition, a cured sealed body with a cured resin film having a flat surface and suppressing warping can be manufactured with improved productivity. [Explanation of symbols]

[0118] 1a, 1b, 1c, 1d Resin sheets 10 Thermosetting resin layer 11 Cured resin layer 20 Base material 30, 31, 32 Adhesive layer 60 Sealing object 70 Encapsulating materials 71 Cured sealant 80 Hardened encapsulated body with hardened resin layer 100 support

Claims

1. A substrate; a thermosetting resin layer formed from a thermosetting resin composition containing a polymer component (A) and a thermosetting component (B), in this order; The storage modulus E' at 23°C of the cured resin layer obtained by thermally curing the thermosetting resin layer is 1.0 x 10 ７ ~1.0 x 10 １３ Pa, a resin sheet used in producing a cured sealed body, comprising: placing an object to be sealed on a surface of the thermosetting resin layer; covering the object to be sealed and a surface of the thermosetting resin layer at least in a peripheral portion of the object to be sealed with a sealing material; thermally curing the sealing material to form a cured sealed body including the object to be sealed; thermally curing the thermosetting resin layer to form a cured resin layer; and removing the cured sealed body with the cured resin layer from the base material after the sealing material and the thermosetting resin layer are thermally cured; The thermosetting resin composition contains an acrylic polymer (A1) as the polymer component (A), The thermosetting component (B) includes an epoxy compound (B1), a thermosetting agent (B2), and a curing accelerator (B3). Resin sheet.

2. The resin sheet according to claim 1 , wherein the thermosetting resin layer is also cured when the sealing material is cured, thereby forming a cured resin layer.

3. The resin sheet according to claim 1 or 2, wherein the thermosetting resin composition further comprises a colorant (C) and / or a coupling agent (D).

4. The resin sheet according to claim 3 , wherein the content of the colorant (C) in the thermosetting resin composition is less than 8 mass %.

5. The storage modulus E′ at 23° C. of the cured resin layer obtained by thermally curing the thermosetting resin layer is 5.0×10 9 Pa ~ 1.0 x 10 １３ The resin sheet according to any one of claims 1 to 4, wherein the resin sheet is Pa.

6. The resin sheet according to any one of claims 1 to 5, wherein the thermosetting resin layer has a thickness of 1 to 500 µm.

7. A method for using a resin sheet having, in this order, a substrate and a thermosetting resin layer formed from a thermosetting resin composition containing a polymer component (A) and a thermosetting component (B), the method comprising: placing an object to be sealed on the surface of the thermosetting resin layer; covering the object to be sealed and at least a surface of the thermosetting resin layer in a peripheral portion of the object to be sealed with a sealing material; The sealing material is thermally cured to form a cured sealing body including the object to be sealed; The thermosetting resin layer is thermally cured to form a cured resin layer; a cured sealed body with a cured resin layer being removed from the base material after the sealing material and the thermosetting resin layer are thermally cured, The thermosetting resin composition contains an acrylic polymer (A1) as the polymer component (A), The thermosetting component (B) includes an epoxy compound (B1), a thermosetting agent (B2) and a curing accelerator (B3). How to use resin sheets.

8. The method for using a resin sheet according to claim 7 , wherein when the sealing material is thermally cured, the thermosetting resin layer is also thermally cured to form a cured resin layer, thereby forming a cured sealed body with a thermosetting resin layer.

9. The method for using a resin sheet according to claim 7 or 8, wherein the content of the colorant (C) in the thermosetting resin composition is less than 8 mass%.

10. The storage modulus E' at 23°C of the cured resin layer obtained by thermally curing the thermosetting resin layer is 1.0 x 10 ７ ~1.0 x 10 １３ The method for using the resin sheet according to any one of claims 7 to 9, wherein the resin sheet is Pa.

11. The method for using a resin sheet according to any one of claims 7 to 10, wherein the thermosetting resin layer has a thickness of 1 to 500 µm.

12. A method for producing a cured sealed body with a cured resin layer using a resin sheet having, in this order, a substrate and a thermosetting resin layer formed from a thermosetting resin composition containing a polymer component (A) and a thermosetting component (B), the method comprising the following steps: A step of placing an object to be sealed on the surface of the thermosetting resin layer A step of covering the object to be sealed and at least the surface of the thermosetting resin layer in the peripheral portion of the object to be sealed with a sealing material. a step of obtaining a cured sealed body with a cured resin layer, the step including: thermally curing the sealing material to obtain a cured sealed body including the object to be sealed; and thermally curing the thermosetting resin layer to form a cured resin layer. A step of removing the cured sealed body with the cured resin layer from the substrate. The thermosetting resin composition contains an acrylic polymer (A1) as the polymer component (A), The thermosetting component (B) includes an epoxy compound (B1), a thermosetting agent (B2), and a curing accelerator (B3). A method for producing a cured sealed body with a cured resin layer.

13. The method for producing a cured sealed body with a cured resin layer according to claim 12 , wherein the thermosetting resin layer is also cured when the sealing material is cured to form a cured resin layer.

14. The method for producing a cured sealed body with a cured resin layer according to claim 12 or 13, wherein a content of the colorant (C) in the thermosetting resin composition is less than 8 mass%.

15. The storage modulus E' at 23°C of the cured resin layer obtained by thermally curing the thermosetting resin layer is 1.0 x 10 ７ ~1.0 x 10 １３ According to any one of claims 12 to 14, The method for producing a cured sealed body having a cured resin layer according to claim 1.

16. 16. The thermosetting resin layer according to claim 12, wherein the thickness of the thermosetting resin layer is 1 to 500 μm. Item 1. A method for producing a cured sealed body with a cured resin layer according to item 1.

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