Electrical insulation layer and semiconductor module

Abstract

To provide an adhesive sheet that prevents air from being caught in at bonding even though it has a different material sheet.SOLUTION: An adhesive sheet is provided with a different material sheet that is flush with other members.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an adhesive sheet, a semiconductor module, and a method for producing the adhesive sheet. [Background technology]

[0002] 2. Description of the Related Art Conventionally, semiconductor modules in which a semiconductor element and a lead frame on which the semiconductor element is mounted are integrated by a resin mold have been widely used. In such semiconductor modules, the lead frame is made of a thick metal plate, and heat generated by the semiconductor elements mounted on the metal plate is thermally conducted to the metal plate, and then this heat is dissipated outside the module via a heat sink. In this type of semiconductor module, the heat sink is usually made of a metal such as aluminum or copper and is exposed to the outside, so an electrical insulating layer is formed between the semiconductor element and the heat sink to ensure safety. With regard to such semiconductor modules, for example, Patent Document 1 listed below describes a semiconductor module having a lead frame attached to the underside of a semiconductor element, with the plate surface being approximately horizontal at the mounting point of the semiconductor element, a heat sink having a plurality of fins, and an electrical insulating layer formed between the heat sink and the lead frame. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2013-30649 A Summary of the Invention [Problem to be solved by the invention]

[0004] The electrical insulating layer of the semiconductor module as described above is formed of an adhesive sheet made of an adhesive resin composition containing an inorganic filler. The adhesive sheet for forming the electrical insulating layer is not only used alone, but also in a laminate of two or more sheets. In this regard, for example, in consideration of the possibility of defects such as voids and cracks in the adhesive sheet, two or more adhesive sheets are laminated to form an electrical insulating layer with high reliability in terms of electrical insulation.

[0005] Incidentally, in order to allow the adhesive sheet to exhibit a function other than that exhibited by the adhesive resin composition, it is conceivable that the sheet body is formed from the adhesive resin composition and further provided with a heterogeneous material sheet formed from a material different from the adhesive resin composition. If the heterogeneous material sheet is made smaller than the area of ​​the sheet body and laminated onto the surface of the sheet body, then both surfaces of the adhesive sheet will be at least partially composed of the adhesive resin composition, and the adhesive properties derived from the adhesive resin composition will be exhibited. Furthermore, by exposing the dissimilar material sheet on one adhesive surface of the adhesive sheet, the adhesive surface exhibits not only the adhesiveness derived from the adhesive resin composition but also a different function due to the dissimilar material sheet. This makes it possible for the adhesive sheet to be used for a variety of purposes by combining the adhesive resin composition with sheets of different materials in various ways. However, if the heterogeneous material sheet protrudes in the thickness direction of the adhesive sheet and a step is formed on the outer peripheral edge of the heterogeneous material sheet, air is likely to be drawn in at the location where the step is formed when the adhesive sheet is adhered. Therefore, when a different material sheet is provided on the adhesive sheet to perform various functions, there is a problem that air is easily entrained during adhesion. Particularly in the semiconductor module, there is a problem that if air is entrained during the formation of the electrical insulating layer, voids are generated.

[0006] The present invention has been made in consideration of the above-mentioned problems, and has an objective of providing an adhesive sheet that is less likely to trap air during bonding even when equipped with sheets of different materials, and to provide a semiconductor module having an electrical insulation layer with excellent insulation reliability. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention provides an adhesive sheet having a first adhesive surface and a second adhesive surface opposite to the first adhesive surface as adhesive surfaces to be adhered to an adherend, the adhesive sheet having a sheet body made of an adhesive resin composition, and further having a heterogeneous material sheet made of a material different from the adhesive resin composition, the heterogeneous material sheet being thinner than the thickness of the sheet body and smaller than the area of ​​the sheet body, the heterogeneous material sheet being embedded in the sheet body so as to be exposed to the first adhesive surface, the first adhesive surface being provided with a first region made of the adhesive resin composition and a second region made of a material different from the adhesive resin composition, the second region being flush with the first region.

[0008] In addition, in order to solve the above-mentioned problems, the present invention provides a semiconductor module comprising a semiconductor element, a metal plate arranged below the semiconductor element to which heat generated by the semiconductor element is transferred, a heat sink arranged below the metal plate to which the heat is transferred from the metal plate, and a resin mold covering the semiconductor element and the metal plate, and further comprising an electrical insulating layer between the heat sink and the metal plate, at least a portion of which is constituted by the above-mentioned adhesive sheet.

[0009] Furthermore, in order to solve the above-mentioned problems, the present invention provides a method for manufacturing an adhesive sheet, comprising: preparing a sheet body in a first state having a two-layer structure, one side of which is composed of copper foil and the other side of which is composed of an adhesive resin composition; removing a portion of the copper foil from the sheet body in the first state to prepare a sheet body in a second state in which a first region in which the adhesive resin composition is exposed on the one side and a second region in which the copper foil remains are formed; and heat-pressing the sheet body in the second state to prepare an adhesive sheet in which the second region is flush with the first region. Effect of the Invention

[0010] The heterogeneous material sheet in the present invention is embedded so as to be flush with the area composed of the adhesive resin composition on the adhesive surface of the adhesive sheet, and therefore air entrapment caused by unevenness during use of the adhesive sheet can be suppressed. That is, according to the present invention, an adhesive sheet is provided which is less likely to trap air during adhesion even when it is provided with sheets of different materials, and a semiconductor module can be provided which has an electrical insulating layer with excellent insulation reliability. [Brief description of the drawings]

[0011] [Figure 1] FIG. 2 is a schematic front view showing the structure of a semiconductor module. [Diagram 2] FIG. 2 is a schematic plan view showing the structure of a semiconductor module. [Diagram 3] 3 is a schematic cross-sectional view showing the structure of a semiconductor module (a cross-sectional view taken along line AA' in FIG. 2). [Figure 4] FIG. 2 is a schematic plan view showing a mode of use of the adhesive sheet. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. First, the semiconductor module will be described. FIG. 1 is a schematic front view of the semiconductor module of the present embodiment, and FIG. 2 is a schematic plan view of the semiconductor module. FIG. 3 is a schematic cross-sectional view showing the internal structure of the semiconductor module of this embodiment, taken along line AA' in FIG.

[0013] As shown in the figure, the semiconductor module of this embodiment has a rectangular, flat box shape in plan view, and has a vertically long rectangular shape in plan view. The semiconductor module has six terminals protruding upward from a top surface and a plurality of fins protruding downward from a bottom surface. In the following, the embodiment of the present invention will be described with the "vertical direction" in the front view of Figures 1 and 3 being the "up-down direction" of the semiconductor module, and this "up-down direction" will also be referred to as the "vertical direction" or "thickness direction". In the following, the direction perpendicular to the "vertical direction" will be referred to as the "horizontal direction" or "planar direction," and in particular, the "lateral direction" when viewed from the front in Figures 1 and 3 will be referred to as the "left-right direction." Furthermore, in the following, the "vertical direction" as viewed from the front in FIG. 2 may be referred to as the "length direction" of the semiconductor module, and the "horizontal direction" as viewed from the front in FIG. 2 may be referred to as the "width direction" of the semiconductor module.

[0014] The semiconductor module 100 of this embodiment has three semiconductor elements 10 at a position that is the center in the thickness direction and the center in the width direction. The semiconductor elements 10 are arranged in the longitudinal direction of the semiconductor module at intervals. In addition, the semiconductor module 100 of this embodiment is provided with a lead member 20 which is a metal plate to which the heat generated by the semiconductor element 10 is transferred and which serves as a conductive path to the semiconductor element 10, and has a heat sink 30 below the lead member 20 to which the heat is transferred from the lead member 20. Furthermore, the semiconductor module 100 has an electrical insulation layer 40 formed of an adhesive sheet between the heat sink and the metal plate.

[0015] The lead member 20 in this embodiment has a shape in which a long plate-shaped metal member is bent at approximately a right angle midway along its longitudinal direction, and has a horizontal portion 21 arranged so that the plate surface is approximately horizontal within the semiconductor module, and a vertical portion 22 extending vertically upward from one end of the horizontal portion 21, and the upper end of the vertical portion 22 forms the terminal. In the semiconductor module 100 of this embodiment, the horizontal portion 21 is arranged below the semiconductor element 10, and the upper surface 21a of the horizontal portion 21 is adhered to the lower surface 10b of the semiconductor element 10, and an electrical connection is made between the lead member 20 and the semiconductor element 10 at the adhesion point.

[0016] Moreover, the semiconductor module 100 of this embodiment further includes a lead member 20' that is separate from the lead member 20 that carries the semiconductor element 10 on the upper surface of the horizontal portion. In the following, the lead member 20 on which the semiconductor element 10 is mounted is referred to as a "first lead member," and the lead member 20' which is different from this is referred to as a "second lead member."

[0017] The second lead member 20' has a horizontal portion 21' and a vertical portion 22', similar to the first lead member 20, and the horizontal portion 21' and the semiconductor element 10 are electrically connected by a bonding wire 60, and the upper end of the vertical portion 22' is provided in the semiconductor module 100 so as to form a terminal separate from the first lead member 20.

[0018] In the semiconductor module 100 of this embodiment, the lower surface 21b of the horizontal portion 21 of the first lead member 20 and the lower surface 21b' of the horizontal portion 21' of the second lead member 20' are adhered to the upper surface 40a of the electrical insulation layer 40, and the lower surface 40b of the electrical insulation layer 40 is adhered to the upper surface 30a of the heat sink 30. In this embodiment, the heat sink 30 comprises a plate-shaped substrate portion 31 whose upper surface is surface-bonded to the lower surface 40b of the electrical insulation layer 40, and a fin portion 32 having a plurality of fins extending downward from the lower surface of the substrate portion 31.

[0019] In addition, in the semiconductor module 100 of this embodiment, a resin mold 50 is formed above the upper surface 40a of the electrical insulation layer 40 in a manner that covers the semiconductor element 10, the first lead member 20, and the second lead member 20'. Therefore, the upper surface 40a of the electrical insulation layer 40 is bonded to the lower surface 50b of the resin mold 50 in the areas other than the areas bonded to the first lead member 20 and the second lead member 20'.

[0020] To form this electrical insulating layer 40, two adhesive sheets 1 and 1x as shown in FIG. 4 (schematic plan view) are used. That is, the electrical insulating layer 40 has a two-layer laminate structure, formed by laminating two adhesive sheets 1, 1x having a common shape in a plan view in the thickness direction with their edges aligned. Of the two adhesive sheets, a first adhesive sheet 1 (hereinafter also referred to as the "first adhesive sheet") and a second adhesive sheet 1x (hereinafter also referred to as the "second adhesive sheet") each have an adhesive surface on both sides, with the first adhesive sheet 1 forming the lower layer side of the electrical insulation layer 40 and the second adhesive sheet 1x forming the upper layer side of the electrical insulation layer 40.

[0021] The first adhesive sheet 1 in this embodiment is interposed between the second adhesive sheet 1x and the heat sink 30 (substrate portion 31), and the second adhesive sheet 1x in this embodiment is interposed between the first adhesive sheet 1 and the lead members 20, 20'. The first adhesive sheet 1 has an upper surface side that is adhered to the second adhesive sheet 1x, which serves as an adherend, as a first adhesive surface 1a, and a lower surface side opposite the first adhesive surface 1a that is adhered to the upper surface of the substrate portion 31 of the heat sink 30 as a second adhesive surface 1b. On the other hand, the second adhesive sheet 1x has an upper surface side that is adhered to the adherend, such as the lead member 20, 20', which constitutes a first adhesive surface 1xa, and a lower surface side opposite the first adhesive surface 1xa that constitutes a second adhesive surface 1xb that is adhered to the first adhesive surface 1a of the first adhesive sheet 1.

[0022] The first adhesive sheet 1 has a sheet body 11 made of an adhesive resin composition, and further has a heterogeneous material sheet 12 made of a material different from the adhesive resin composition, which is thinner than the thickness of the sheet body 11 and smaller than the area of ​​the sheet body 11. In the first adhesive sheet 1, the heterogeneous material sheet 12 is embedded in the sheet body 11 so as to be exposed to the first adhesive surface 1a, and the first adhesive surface 1a is provided with a first region 1a1 made of the adhesive resin composition and a second region 1a2 made of the material different from the adhesive resin composition. The second region 1a2 of the first adhesive sheet 1 is flush with the first region 1a1, and no step is generated at the boundary between the first region 1a1 and the second region 1a2. The first adhesive surface 1a of the first adhesive sheet 1 is composed of two materials with different properties, while the second adhesive surface 1b is composed only of the adhesive resin composition that constitutes the sheet body 11.

[0023] The second adhesive sheet 1x of this embodiment is composed only of an adhesive resin composition, and does not include a dissimilar material sheet 12. Therefore, the first adhesive surface 1xa and the second adhesive surface 1xb of the second adhesive sheet 1x, like the second adhesive surface 1b of the first adhesive sheet 1, are made only of the adhesive resin composition. The second region 1a2 of the first adhesive sheet 1 is located in the center of the first adhesive surface 1a, and is provided in a state where the periphery is completely surrounded by the first region 1a1. Therefore, the dissimilar material sheet 12 of this embodiment is embedded in the adhesive resin composition and constitutes the electrical insulating layer 40 together with the adhesive resin composition. The electrical insulation layer 40 exhibits different characteristics between the central portion, where the characteristics of the dissimilar material sheet 12 are relatively strongly reflected, and the peripheral portion, where the characteristics are less likely to be affected by the dissimilar material sheet 12.

[0024] Here, the resin mold 50 can be generally formed by a method of casting a resin composition in a heated and molten state in the same manner as in conventional semiconductor modules. In this case, the outer periphery of the electrical insulation layer 40 receives a stronger pulling force in the thickness direction due to the cure shrinkage of the resin mold 50 than the central portion. In addition, stresses that occur at the interface between resin mold 50 and electrical insulation layer 40 and stresses that occur at the interface between heat sink 30 and electrical insulation layer 40 due to differences in temperature between when semiconductor module 100 is operating and when it is at rest, and differences in the thermal expansion coefficients of resin mold 50 and heat sink 30, tend to act more strongly on the outer periphery than on the center. In this embodiment, the outer periphery of the electrical insulation layer 40 is formed only from the adhesive resin composition, and therefore can exhibit strong resistance to the above-mentioned stress. The central portion of the electrical insulation layer 40 may be more susceptible to interfacial peeling than the peripheral portion due to the presence of the dissimilar material sheet 12, but the dissimilar material sheet makes it easier for the central portion to exhibit various properties that are different from those of the peripheral portion. Furthermore, when the first adhesive sheet 1 and the second adhesive sheet 1x are laminated, the electrical insulation layer 40 has no steps around the heterogeneous material sheet 12, which prevents air from being drawn in and also prevents the formation of voids.

[0025] The adhesive resin composition used to form the electrical insulation layer 40 as described above preferably has excellent electrical insulation properties, and 13 It is preferable that the volume resistivity is Ω·cm or more. The volume resistivity of the adhesive resin composition is usually 1×10 18 Ω·cm or less. The volume resistivity can be measured, for example, by the method specified in JIS C2139, and can be obtained by carrying out the above-mentioned measurement on a sheet produced using the adhesive resin composition.

[0026] In order to provide the electrical insulating layer 40 with excellent thermal conductivity, the adhesive resin composition preferably contains, together with the resin, an inorganic filler having a higher thermal conductivity than the resin. The resin contained in the adhesive resin composition in this embodiment is not particularly limited, and may be a thermoplastic resin or a thermosetting resin. Examples of the thermoplastic resin include polyethylene resin, polypropylene resin, ethylene-vinyl acetate copolymer resin, polyvinyl chloride resin, polystyrene resin, phenoxy resin, acrylic resin, polyamide resin, polyamideimide resin, polyimide resin, polyetheramideimide resin, polyethersulfide resin, polyphenylene sulfide resin, polyetherimide resin, and thermoplastic elastomer. In addition, when the thermosetting resin is used, examples of the resin include an epoxy resin, a phenol resin, and an unsaturated polyester resin. Among the resins exemplified above, many of the thermoplastic resins are unlikely to exhibit high adhesive strength by themselves. Therefore, when a thermoplastic resin is contained in the adhesive resin composition, a tackifier such as a tackifier may be contained in addition. Among the above resins, epoxy resins are preferred because they exhibit high adhesiveness even without containing a tackifier and also have high acceptability for inorganic fillers. That is, the adhesive resin composition in this embodiment is preferably an epoxy resin composition.

[0027] Examples of the epoxy resin include bisphenol type epoxy resins such as bisphenol A type epoxy resins and bisphenol F type epoxy resins; and novolac type epoxy resins such as phenol novolac type epoxy resins and cresol novolac type epoxy resins. The epoxy resin may be a modified product that has been subjected to CTBN modification or the like. The epoxy resin may be of the high molecular weight type, such as those called phenoxy resins. The adhesive resin composition may contain one type of the above-mentioned epoxy resin alone or two or more types of the above-mentioned epoxy resins.

[0028] The adhesive resin composition may further contain a curing agent or a curing accelerator for curing the epoxy resin. The curing agent is not particularly limited, but examples thereof include amine-based curing agents such as diaminodiphenylsulfone, dicyandiamide, diaminodiphenylmethane, and triethylenetetramine; phenol-based curing agents such as phenol novolac resin, aralkyl-type phenol resin, dicyclopentadiene-modified phenol resin, naphthalene-type phenol resin, and bisphenol-type phenol resin; and acid anhydrides. The curing accelerator is not particularly limited, but may be an imidazole, or an amine-based curing accelerator such as triphenyl phosphate (TPP) or boron trifluoride monoethylamine. Regarding the curing agent and the curing accelerator, one kind may be contained alone in the adhesive resin composition, or two or more kinds of at least one of them may be contained in the adhesive resin composition.

[0029] The inorganic filler contained in the adhesive resin composition may be any of those commonly used to impart thermal conductivity to resin products, but boron nitride is particularly preferred because of its excellent thermal conductivity. Moreover, it is preferable to use particles (aggregated particles) in which a plurality of plate-like primary particles of boron nitride are aggregated together. The agglomerated particles that can be used include agglomerated particles (granular particles) that are formed in a state in which they are entirely granular, and agglomerated particles (aggregated particles) that are in an aggregated state in which the scale-like structure of the primary particles of boron nitride is gathered to such an extent that it can be distinguished.

[0030] In order to allow the electrical insulating layer 40 to exhibit excellent thermal conductivity, it is preferable that the adhesive resin composition contains the above-mentioned epoxy resin and inorganic filler, and that the content of the inorganic filler is 50 volume % or more. The content of the inorganic filler is more preferably 55% by volume or more, and particularly preferably 60% by volume or more. In order to allow the adhesive resin composition to exhibit excellent adhesiveness, the content of the inorganic filler in the adhesive resin composition is preferably 75 vol % or less, and more preferably 70 vol % or less.

[0031] The adhesive resin composition preferably contains epoxy resins in a proportion of 90 mass % or more, more preferably 95 mass % or more, of all resins contained therein, and it is particularly preferable that the adhesive resin composition contains substantially no resins other than epoxy resins.

[0032] In addition to the above-mentioned components, the adhesive resin composition may appropriately contain, in addition to the above-mentioned components, dispersants, antioxidants, antioxidants, processing aids, stabilizers, defoamers, flame retardants, thickeners, pigments, and other substances that are generally used as compounding chemicals for rubber and plastics.

[0033] In this embodiment, the heterogeneous material sheet for forming the electrical insulation layer 40 together with the adhesive resin composition is embedded in the adhesive resin composition to form the electrical insulation layer 40, and therefore the heterogeneous material sheet does not necessarily have to be electrically insulating and may be conductive.

[0034] Examples of the different material sheets include resin films, rubber sheets, and metal films. Examples of the heterogeneous material sheets include fiber sheets made of resin fibers, carbon fibers, glass fibers, ceramic fibers, metal fibers, etc., ceramic sheets, fiber sheets of glass fibers, etc. Furthermore, the different material sheet does not need to be flexible and may be a ceramic plate, a glass plate, a metal plate, or the like. The effects that the heterogeneous material sheet can provide to the adhesive sheet or electrical insulating layer include effects on mechanical properties such as bending / tensile strength and flexibility, effects on thermal properties such as thermal decomposition and flame retardancy, and effects on electromagnetic properties such as dielectric performance and shielding performance.

[0035] The electrical insulating layer 40 usually has a thickness of 10 μm or more and 1000 μm or less. The electrical insulating layer 40 preferably has a thickness of 50 μm or more and 500 μm or less. The first adhesive sheet 1 and the second adhesive sheet 1x usually have a thickness of 5 μm or more and 500 μm or less, and preferably have a thickness of 25 μm or more and 250 μm or less. The first adhesive sheet 1 and the second adhesive sheet 1x may have the same thickness or may have different thicknesses. The different material sheet provided on the first adhesive sheet 1 may have a thickness of, for example, 1 μm or more and 200 μm or less. The thickness of the different material sheet is preferably 1 / 100 to 1 / 2 of the thickness of the first adhesive sheet 1, and more preferably 1 / 10 to 1 / 3. The size (area) of the dissimilar material sheet can be, for example, 10% or more and 80% or less of the area of ​​the first adhesive sheet 1.

[0036] The dissimilar material sheet is preferably an electrolytic copper foil, since this easily exhibits excellent adhesion to the adhesive resin composition. The side of electrolytic copper foil that was in contact with the electrolytic drum during production is flat, while the side that was in contact with the electrolyte has irregularities of several micrometers in height. The flat surface of an electrolytic copper foil is called a glossy surface or a shining surface, while the surface with irregularities is called a matte surface. However, it is preferable that the second region 1a2 of the first adhesive sheet 1 be configured as a shining surface, since this makes it difficult for air to become trapped between the second adhesive sheet 1x and the second region 1a2. That is, in the first adhesive sheet 1 in this embodiment, it is preferable that the dissimilar material sheet is an electrolytic copper foil having a matte surface and a shining surface, and the second region 1a2 is constituted by the shining surface of the electrolytic copper foil.

[0037] When copper foil is used as the dissimilar material sheet, the method for producing the first adhesive sheet 1 preferably includes the following steps. a) A step of dispersing an adhesive resin composition in an organic solvent to prepare a coating liquid b) A step of applying the coating liquid to one side of a copper foil and drying the coating liquid to produce a sheet body in a first state having a two-layer structure in which one side is constituted by copper foil and the other side is constituted by an adhesive resin composition. c) removing a portion of the copper foil from the sheet body in the first state to produce a sheet body in a second state in which a first region in which the adhesive resin composition is exposed and a second region in which the copper foil remains are formed on the one side. d) heat-pressing the sheet body in the second state to produce an adhesive sheet in which the second region is flush with the first region;

[0038] The above-mentioned "step a)" can be carried out using, for example, an apparatus such as a homogenizer or a mixer. The above-mentioned "b) step" can be carried out using, for example, a device such as a gravure coater or a kiss coater, or a heating / drying oven. The above-mentioned "c) step" can be carried out using, for example, an etching machine. The above-mentioned "step d)" can be carried out using, for example, an apparatus such as a vacuum heat press. When an epoxy resin composition is used as the adhesive resin composition, it is preferable to adjust the B-stage state of the epoxy resin composition in the "d) step" by adjusting the amount of heat applied, for example. The above-mentioned production method can provide the effect of easily producing a desired adhesive sheet. Furthermore, in the adhesive sheet obtained by the above manufacturing method, the steps around the copper foil on the exposed side of the copper foil disappear in "step d)", making it possible to prevent the entrapment of air bubbles due to the steps during bonding.

[0039] In the above example, an embodiment of the present invention is illustrated by taking as an example a case in which an adhesive sheet having a heterogeneous material sheet and an adhesive sheet not having a heterogeneous material sheet are stacked to form an electrical insulation layer of a semiconductor module, but the use of the adhesive sheet of the present invention is not limited to such a case. For example, the electrical insulation layer may be formed of only one adhesive sheet having sheets of different materials, or may be formed by laminating a plurality of adhesive sheets having sheets of different materials. Furthermore, the adhesive sheet of the present invention is not limited to use in forming an electrical insulating layer of a semiconductor module, and its use is not particularly limited. Furthermore, the present invention is not limited to the above examples. [Explanation of symbols]

[0040] 1 Adhesive sheet 1a 1st adhesive surface 1a1 1st area 1a2 2nd area 10 Semiconductor elements 11 Seat body 12 Different material sheets 20 Lead material (metal plate) 30 Heat sink 40 Electrical insulation layer 50 Resin mold

Claims

1. An electrical insulating layer having a laminated structure of a first adhesive sheet and a second adhesive sheet, each of the first adhesive sheet and the second adhesive sheet has a first adhesive surface and a second adhesive surface opposite to the first adhesive surface as an adhesive surface to be adhered to an adherend; The first adhesive sheet is A sheet body made of an adhesive resin composition containing an epoxy resin and an inorganic filler, and the content of the inorganic filler is 50 volume % or more; The adhesive layer is made of a material different from the adhesive resin composition, and is thinner than the sheet body; and a dissimilar material sheet having an area smaller than that of the sheet body, the different material sheet is embedded in the sheet body so as to be exposed to the first adhesive surface, the first adhesive surface is provided with a first region made of the adhesive resin composition and a second region made of the material different from the adhesive resin composition, the second region being flush with the first region, The second adhesive sheet is the adhesive layer is in contact with the first adhesive surface of the first adhesive sheet and is composed only of an adhesive resin composition containing an epoxy resin and an inorganic filler; Electrical insulation layer.

2. The dissimilar material sheet is an electrolytic copper foil having a matte surface and a shining surface, The electrical insulation layer of claim 1 , wherein the second region is constituted by a shining side of the electrolytic copper foil.

3. the semiconductor device includes a semiconductor element, a metal plate disposed below the semiconductor element to which heat generated by the semiconductor element is transferred, a heat sink disposed below the metal plate to which the heat is transferred from the metal plate, a resin mold covering the semiconductor element and the metal plate, and an electrical insulating layer disposed between the heat sink and the metal plate, A semiconductor module, wherein the electrical insulation layer is formed of the electrical insulation layer according to claim 1 or 2.

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