Sheet-type sintered bonding material

Abstract

The present invention relates to a sheet-like sintered bonding material having a metal layer made of a plate-like or foil-like metal and a tacky adhesive layer containing metal nanoparticles and a solvent on both sides of the metal layer, wherein the metal nanoparticles are composite metal nanoparticles in which an organic coating layer made of one or more aliphatic carboxylic acids having 1 to 10 or 12 carbon atoms is formed around a metal core with an average particle size of 1 to 200 nm made of an aggregate of metal atoms; a joint formed by joining the sheet-like sintered bonding material and a bonding member; and electrical equipment, electronic equipment, semiconductor components, or heat dissipation components using the said joint.

Description

Technical Field

[0001] The present invention relates to a sheet-shaped sintered bonding material and electrical equipment, electronic equipment, semiconductor components, and heat dissipation components using the sheet-shaped sintered bonding material.

Background Art

[0002] In the manufacture of semiconductor modules such as power control units mounted on xEVs such as electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, and fuel cell vehicles, as a method of joining semiconductor chips and heat dissipation members to lead frames, insulating circuit boards, etc., regardless of the size of the semiconductor chips and heat dissipation parts, from the viewpoint of easy joining without the need for a printing process, a method is known in which a sheet-shaped bonding material rather than a paste is placed between the substrate and the semiconductor chip or heat dissipation member and sintered and joined.

[0003] Examples of the bonding material include a metal layer formed from a bulk material of a metal and a metal bonding layer laminated and provided by coating or supporting on both surfaces of the metal layer. The bulk material is a single metal selected from copper, silver, gold, platinum, and palladium, or an alloy composed of at least two or more selected from copper, silver, platinum, and palladium. The bulk material is a foil, a metal mesh, or a metal porous body. The metal layer is formed by molding a dispersion solution in which metal fine particles composed of at least one selected from the group consisting of a metal simple substance, an alloy, and a metal compound are dispersed in an organic solvent and coated with a polymer dispersant into a film shape, and the average primary particle size of the metal fine particles is 5 to 500 nm. A heat-bonding material (Patent Document 1) and the like are known.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

[0005] However, the inventors have confirmed that the sheet-like bonding material is formed from a layer of polymer dispersant coated on a metal layer or a bonding layer in which metal nanoparticles are dispersed. However, when the components to be bonded are mounted onto the sheet-like bonding material during assembly, the lack of tackiness in the sheet-like bonding material causes the substrate and the electronic components such as semiconductor chips to move to locations other than their original positions (so-called misalignment). If this is sintered, the substrate product itself will not be able to exhibit the desired performance such as electrical conductivity and thermal conductivity, resulting in defects and reduced productivity. Furthermore, it was found that, as described above, insufficient adhesion between the member to be joined and the sheet-like bonding material can cause the member to move, resulting in a gap between the member and the sheet-like bonding material. This gap can then cause voids to form during sintering and joining, potentially leading to defects as hot spots in the product.

[0006] Tackiness refers to the force with which a material adheres to an object (the surface to be bonded) in a short time when lightly touched, and describes a property where the surface has an adhesive or sticky feel. In this invention, tackiness refers to the property of using the adhesiveness and stickiness of a sheet-like sintered bonding material to bond and fix components to be bonded (joining members) that constitute electrical equipment, electronic equipment, semiconductor components, heat dissipation components, etc., by contacting or applying pressure at room temperature or heated.

[0007] Therefore, the present invention solves the above-mentioned problems and specifically provides a sheet-shaped sintered bonding material, a bonding part using the sheet-shaped sintered bonding material, electrical equipment, electronic equipment, semiconductor components, heat dissipation components, etc., which has excellent tackiness to bonding members constituting electrical equipment, electronic equipment, semiconductor components, heat dissipation components, etc., and which prevents defects caused by "misalignment" by stably fixing various components in the desired position due to this tackiness, thereby contributing to improved productivity. [Means for solving the problem]

[0008] That is, the first embodiment of the present invention comprises a metal layer made of a plate-shaped or foil-shaped metal, The metal layer has a tacky adhesive layer on both sides containing metal nanoparticles and a solvent. The aforementioned metal nanoparticles are composite metal nanoparticles in which an organic coating layer consisting of one or more aliphatic carboxylic acids having 1 to 10 or 12 carbon atoms is formed around a metal nucleus with an average particle size of 1 to 200 nm, which is composed of an aggregate of metal atoms. This is a sheet-like sintered bonding material. The solvent may contain one or more high-viscosity solvents. The content of the highly viscous solvent in the adhesive layer may be 0.1 to 20.0% by mass. The thickness of the metal layer may be 10 to 1000 μm, and the thickness of the adhesive layer may be 20 to 100 μm. The metal atoms constituting the metal nanoparticles may be individual metals consisting of copper, gold, platinum, palladium, or silver, or composites thereof. The adhesive layers on both sides of the metal layer may be used to fix the joining member after it has been mounted onto the sheet-like sintered joining material. The adhesive layer may contain metal nanoparticles, a filler, a solvent, and a dispersant. The metal layer may have one or both sides of it surface-treated with one or more of the following: copper, gold, silver, platinum, or palladium, or a composite thereof.

[0009] A second embodiment of the present invention is a joint joined with the sheet-like sintered bonding material, or an electrical device, electronic device, semiconductor component, or heat dissipation component using said joint. [Effects of the Invention]

[0010] The sheet-shaped sintered bonding material of the present invention has superior tackiness to the members to be joined (joining members) that constitute electrical equipment, electronic equipment, semiconductor components, heat dissipation components, etc., compared to conventional products. With the sheet-shaped sintered bonding material that has been given tackiness, the joining members are firmly adhered to and fixed to the sheet-shaped bonding material in the pre-joining process, preventing defects due to "misalignment". Since the joining members do not move during the process, productivity such as handling and yield can be improved, and electrical equipment, electronic equipment, semiconductor components, heat dissipation components, etc., with desired performance can be manufactured efficiently. [Brief explanation of the drawing]

[0011] [Figure 1] In Test Example 3, the sample that underwent temporary bonding in Test Example 1 was fired to bond it, then embedded in resin, polished, and the resulting SEM image shows the result of observing the bonded cross-section. [Modes for carrying out the invention]

[0012] The sheet-like sintered bonding material of the present invention comprises a metal layer made of a plate-shaped or foil-shaped metal, On both sides of the metal layer, a tacky adhesive layer containing metal nanoparticles and a solvent It is a bonding material that has [a certain characteristic].

[0013] The plate-like or foil-like metal constituting the aforementioned metal layer refers to a metal member with a thickness of 10 μm or more. While it is preferable for the plate-shaped or foil-shaped metal to have a uniform thickness, it is not required to have a uniform thickness. Furthermore, the plate-shaped or foil-shaped metal may have holes, such as those in punched metal, as needed. If holes are present or if it is a mesh, there are no restrictions on the size or number of holes within the scope of achieving the effects of the present invention, and in the case of a mesh, there are no restrictions on the thickness of the metal wire or the size of the openings of the mesh. The foil-shaped or plate-shaped metal does not need to be solid; depending on the application, it may be made by weaving wire-shaped metal or by thinning short metal fibers. In the present invention, from the viewpoints of bonding reliability and workability, the thickness of the metal layer is preferably 10 to 1000 μm, more preferably 10 to 100 μm, still more preferably 20 to 70 μm, and particularly preferably 20 to 50 μm.

[0014] Regarding the area of the metal layer, it may be appropriately adjusted according to the member area required for bonding in electric devices, electronic devices, semiconductor components, heat dissipation components, etc., and there is no particular limitation.

[0015] Examples of the material of the metal layer include iron, copper, silver, gold, aluminum, nickel, platinum, palladium, alloys composed of two or more of these, and stainless steel, etc., but there is no particular limitation.

[0016] Also, one surface or both surfaces of the metal layer may be surface-treated with one kind selected from the group of copper, gold, silver, platinum, or palladium, or one or more kinds of composites thereof. Examples of the surface treatment include dry plating such as physical vapor deposition (PVD) and chemical vapor deposition (CVD), wet plating such as electroplating and electroless plating, chemical conversion treatment (ferrite) and anodic oxidation treatment (alumite), hot dip galvanizing, sputtering treatment, etc., and can be appropriately selected within the range having the effects of the present invention. There is no particular limitation on the combination of the metal constituting the metal layer and the metal constituting the thin film formed by the surface treatment. Also, there is no particular limitation on the thickness of the thin film.

[0017] In the present invention, layers (adhesive layers) with a desired thickness are formed on both surfaces of the metal layer. When the surfaces of these adhesive layers are brought into contact and pressurized with bonding members constituting electric devices, electronic devices, semiconductor components, heat dissipation components, etc. at normal temperature or with heating, these bonding members can be adhered and fixed at desired positions so as not to move. In the present invention, as described above, mounting refers to mounting the bonding member while bringing it into contact and pressurizing it at normal temperature or with heating. Regarding the temperature of the heating, it may be any temperature at which tackiness is exhibited in the adhesive layer, and there is no particular limitation. Also, regarding the degree of contact or pressure, it is only necessary that the surface of the adhesive layer can be adhered so as not to move on the surface of the joining member, and there is no particular limitation. As an example of an adhesive method for adhering an object to be joined to a substrate, the following steps may be mentioned First step: Attach the sheet-like sintered joint material of the present invention to a predetermined position on the substrate. Second step: Then, mount a joining member such as a chip on the sheet-like sintered joint material of the present invention. Third step: After mounting the joining member, temporarily fix the substrate, the sheet-like sintered joint material of the present invention, and the object to be joined by applying a desired pressure and heating. By the temporary fixing, tackiness is exhibited in the sheet-like sintered joint material of the present invention, and an excellent effect is achieved in that the positional deviation of the object to be joined does not occur even in subsequent processes such as handling.

[0018] Also, in the present invention, the tackiness may be "hot tackiness" in which adhesiveness is exhibited by heating when there is no tackiness at normal temperature. In this case, even when there is no tackiness at normal temperature, the sheet-like sintered joint material can be easily handled.

[0019] Note that the sheet-like sintered joint material adhered and fixed (also referred to as temporary joining) to the joining member as described above can be peeled off if necessary.

[0020] The presence or absence of tackiness in the present invention is, for example, placing a 10 mm × 10 mm sheet-like sintered joint material on a 50 mm × 50 mm, 1 mm thick metal plate such as copper or aluminum, and placing a 10 mm × 10 mm, 1 mm thick metal plate such as copper or aluminum on the sheet-like sintered joint material and applying pressure at normal temperature or applying pressure while heating as described above. If it does not fall when turned upside down, it is evaluated as having tackiness or hot tackiness.

[0021] The sheet-like sintered bonding material of the present invention, by possessing tackiness as described above, can stably fix various parts in a desired position. The strength of this fixation does not need to be limited to preventing the joined members from moving away from their original positions (misalignment). For example, if a shear test specimen conforming to JIS Z 3198-5 is prepared using the sheet-type sintered bonding material of the present invention and its shear strength is measured, a strength of 0.01 MPa or higher is sufficient to stably fix members constituting electrical equipment, electronic equipment, semiconductor components, and heat dissipation components.

[0022] The metal nanoparticles contained in the adhesive layer are composite metal nanoparticles in which an organic coating layer consisting of one or more aliphatic carboxylic acids having 1 to 10 or 12 carbon atoms is formed around a metal nucleus with an average particle size of 1 to 200 nm, which is made up of an aggregate of metal atoms.

[0023] From the viewpoint of easily exhibiting the effects of the present invention, the metal atoms constituting the metal nanoparticles may be individual metals consisting of copper, gold, platinum, palladium, or silver, or composites thereof.

[0024] Examples of aliphatic carboxylic acids having 1 to 10 or 12 carbon atoms include saturated fatty acids such as formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, and lauric acid; dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid, and maleic acid; and tricarboxylic acids such as aconitic acid, but are not particularly limited.

[0025] The particle size of the aforementioned metal nanoparticles can be determined, for example, by measuring the diameter observed with an electron microscope and calculating the average particle diameter.

[0026] The aforementioned metal nanoparticles can be produced, for example, based on the methods described in Japanese Patent No. 4680313, Japanese Patent No. 5256281, Japanese Patent No. 5306322, Japanese Patent No. 5398935, etc.

[0027] The two adhesive layers formed on the surface of the metal layer may contain the same metal nanoparticles, or they may contain metal nanoparticles of different types or sizes. Furthermore, a single adhesive layer may contain only one type of metal nanoparticle, or a mixture of two or more types. For example, when using composite silver nanoparticles, the two adhesive layers may contain only composite silver nanoparticles, or one adhesive layer may contain composite silver nanoparticles and the other adhesive layer may contain composite metal nanoparticles other than silver, or one adhesive layer may contain composite silver nanoparticles and the other adhesive layer may contain composite silver nanoparticles and composite metal nanoparticles other than silver. Furthermore, even if the composite metal nanoparticles are made of the same material, they may contain two or more particles of different sizes.

[0028] The solvent contained in the adhesive layer is a highly viscous solvent that exhibits tackiness due to the presence of the metal nanoparticles. It has the advantage of being easily volatilized during sintering, resulting in less void formation in the bonded layer formed by the sintering of the metal nanoparticles.

[0029] The aforementioned high-viscosity solvent is not limited as long as it does not inhibit the sintering of metal nanoparticles, and examples include terpenes and polyols. Examples of terpenes include terpineol and tersolve THA90. (Product name) Examples include isobornylcyclohexanol, Examples of polyols include ethylene glycol, glycerin, triethanolamine, polyethylene glycol, styrene-acrylonitrile copolymer, and polyols containing fine particles such as polyurea, with isobornylcyclohexanol being particularly preferred. The high-viscosity solvent used as the solvent may be one type or a mixture of two or more types.

[0030] Furthermore, from the viewpoint of tackiness to bonding members such as semiconductor chips, the content of the high-viscosity solvent in the adhesive layer is preferably 0.1 to 20.0% by mass, and more preferably 0.1 to 5.0% by mass. In the present invention, the content of the high-viscosity solvent can be calculated, for example, by subtracting the amount of solvent evaporation during drying from the content of the high-viscosity solvent in the paste containing metal nanoparticles and solvent used to form the adhesive layer.

[0031] Furthermore, in the present invention, in addition to the high-viscosity solvent, a low-viscosity solvent may be used for viscosity adjustment. The low-viscosity solvent can be any solvent that can adjust the viscosity when mixed with the high-viscosity solvent, and there are no particular limitations on its type or content.

[0032] The adhesive layer may contain a filler and a dispersant. The aforementioned filler can be any type that can be used in conductive pastes, etc., and is not particularly limited, but examples include one or more particulate metal fillers selected from gold, silver, copper, platinum, and palladium. The aforementioned dispersant can be any agent that can be used in conductive pastes, etc., and is not particularly limited, but examples include saturated fatty acids with 4 to 18 carbon atoms such as butanoic acid, hexanoic acid, octanoic acid, decanoic acid, lauric acid, myristic acid, pentadecylic acid, palmitic acid, and stearic acid; unsaturated fatty acids with 14 to 18 carbon atoms such as myristoleic acid, palmitoleic acid, oleic acid, elaidic acid, linoleic acid, and linolenic acid; aliphatic amines such as octylamine, laurylamine, oleylamine, myristylamine, and dodecyldimethylamine; tertiary amines such as didodecyldimethylamine and trioctylamine; aromatic amines such as naphthalenediamine; higher amines such as octadecylamine; triamines such as pentamethyldiethylenetriamine; and heterocyclic aromatic amines such as pyridine.

[0033] Furthermore, the adhesive layer may contain a binder such as a solid solvent or a polymer. The type and amount of binder, such as a solid solvent or polymer, are not particularly limited, as long as the adhesive layer can exert the desired effect.

[0034] The composition of the metal nanoparticles, fillers, and dispersants in the adhesive layer is not particularly limited, as long as the content of each component is sufficient to fix the bonded members after mounting, depending on the material type of each component.

[0035] The thickness of the adhesive layer can be adjusted according to the purpose of sintering, and is not particularly limited. However, from the viewpoint of easily fixing the joining members constituting electrical equipment, electronic equipment, semiconductor components, heat dissipation components, etc., in the desired position, a thickness of 20 to 100 μm is preferred, and 20 to 70 μm is more preferred. Furthermore, the thickness of the adhesive layer provided on one side of the metal layer may be constant, or it may have thin and thick portions, as long as the effects of the present invention are obtained. For example, the thickness may increase in a gradual manner from one direction to the other. Furthermore, the thickness of the adhesive layers provided on both sides of the metal layer may be the same or different, as long as the effects of the present invention are obtained. For example, electronic devices and semi-automotive modules may have design thickness limitations, but because the sheet-like sintered bonding material of the present invention firmly adheres and fixes the bonding members, the bonding strength can be maintained at a certain level of sufficient strength without decreasing within the thickness range of the adhesive layer.

[0036] The sheet-like sintered bonding material of the present invention can be manufactured, for example, by attaching a mixture containing the metal nanoparticles and the solvent, and optionally the filler and dispersant, to both sides of a plate-like or foil-like metal that will become a metal layer, using a known method to form an adhesive layer, and then drying the adhesive layer until the solvent content reaches a desired amount, if necessary.

[0037] The mixing of the metal nanoparticles and the solvent can be any method that can mix the metal nanoparticles, and is not particularly limited.

[0038] Methods for attaching the mixture to both sides of a plate-shaped or foil-shaped metal include, but are not limited to, screen printing, spray coating, roll coating, spin coating, dispensing, and inkjet methods.

[0039] Furthermore, when manufacturing the sheet-like sintered bonding material of the present invention, the adhesive layers on both sides of the metal layer contain metal nanoparticles, resulting in superior physical properties such as electrical conductivity, thermal conductivity, bonding characteristics, and bonding reliability.

[0040] The sheet-like sintered bonding material of the present invention obtained as described above can be used to bond various components (bonding members) that constitute electrical equipment, electronic equipment, semiconductor components, or heat dissipation components.

[0041] In the present invention, the member to be joined (joining member) may be any member that constitutes an electrical device, electronic device, semiconductor component, or heat dissipation component, and is not particularly limited.

[0042] The joining method can be the same as with conventional sheet-type joining materials. For example, in electrical equipment, electronic equipment, semiconductor components, or heat dissipation components, one adhesive layer of the sheet-type sintered bonding material of the present invention is bonded to the surface of member A to be joined, and then another member B to be joined is bonded to the other adhesive layer, thereby combining a laminated component consisting of member A - sheet-type sintered bonding material - member B, and then this laminated component is heated and sintered to a desired temperature to sinter the metal nanoparticles contained in the adhesive layer, forming a metal sintered product and thus enabling bonding. In this invention, the conditions for sintering, such as temperature and time, are not particularly limited, as long as they are at a temperature at which the metal nanoparticles used can be fired.

[0043] In the joined component, the structure consists of a laminated layer of member A - a bonding layer made of sintered metal nanoparticles - a metal layer - a bonding layer made of sintered metal nanoparticles - member B. Both bonding layers have a uniform thickness and few voids, allowing member A and member B to be firmly joined without misalignment. Furthermore, since the component has a bonding layer made of uniform metal nanoparticles, and the occurrence of voids and cracks in the bonding layer and bonding interface is extremely low, it can contribute to highly reliable bonding and the completion of components. [Examples]

[0044] In the following embodiment, the following materials were used. (Metal paste) • Metal paste 1: A paste-like composition containing (commercially available, composite silver nanoparticles (average particle size of metal cores: 1-200 nm, material of the organic coating layer covering the metal cores: aliphatic carboxylic acid with 1-10 or 12 carbon atoms), solvent (isobornylcyclohexanol), filler (silver-coated copper filler with a particle size of 5 μm), and dispersant (linoleic acid). (metal layer) • Metal foil 1: Copper foil, thickness: 30 μm

[0045] Example 1 [Method for manufacturing sheet-like sintered bonding material 1] A sheet-like sintered bonding material 1 was prepared using the materials shown in Table 1. Specifically, metal paste 1 was applied to both sides of metal foil 1 so that the thickness of the adhesive layer after drying was 50 μm, and the foil was placed in a high-temperature constant-temperature oven set to 100°C and dried for 20 minutes. The total thickness was 130 μm, and the solvent content was 2% by mass. The coating method used was screen printing, with a #120 metal mesh (open area 41%, wire diameter 23 μm, mesh thickness 41 μm) and a squeegee with a hardness of 80.

[0046] The measurement results for each part of the obtained bonding material are shown in Table 1.

[0047] [Table 1]

[0048] Test Example 1 Evaluation of Sheet-like Bonding Material Samples: (1) Evaluation of Tackiness (Temporary Bonding) A sheet-like bonding material 1, cut to an appropriate size, prepared in Example 1, was placed between two oxygen-free copper test pieces, A (size: 2 mm thick, 5 mm in diameter) and B (size: 5 mm thick, 10 mm in diameter). A temporary bonding was performed using a firing apparatus (upper and lower pulse heat unit bonding apparatus) manufactured by Japan Avionics Co., Ltd., at a temperature of 180°C, a pressure of 2.5 MPa, and a holding time of 10 seconds to obtain a temporary bonded object 1 as a test piece. To confirm the tackiness of the temporary joint 1, we held test piece B with test piece A facing downwards and gently shook it up and down and side to side. We confirmed that the joint remained intact and test piece A did not peel off or fall off.

[0049] Test Example 2 Evaluation of Sheet-like Bonding Material Samples: (2) Measurement of Shear Strength The shear strength was measured in accordance with JIS Z 3198-5. Specifically, the shear strength of the test specimen prepared in Test Example 1 was measured using an A&D TENSILON strength tester as a No. 2 shear test specimen in accordance with JIS Z 3198-5, and a shear strength of 0.1 MPa (2 N) was confirmed. Furthermore, the absence of voids in the fracture surface of the samples whose shear strength was measured was confirmed using an optical microscope. Therefore, it can be seen that the sheet-like sintered bonding material of the present invention has excellent tackiness to the bonding members, and this tackiness allows various parts to be stably fixed in the desired position in the temporary bonding state.

[0050] Test Example 3: Confirmation of Joint Strength The sample with the preliminary bonding obtained in Test Example 1 was bonded using a firing apparatus (upper and lower pulse heat unit bonding apparatus) manufactured by Japan Avionics Co., Ltd., at a temperature of 300°C, a pressure of 10 MPa, and a holding time of 180 seconds.

[0051] Shear strength was measured using an A&D TENSILON strength testing machine and a strength of 56 MPa was confirmed.

[0052] Furthermore, to confirm the bonding state, the bonded samples were embedded in resin, polished, and the bonded cross-section was observed using a JEOL JCM-5700. The results are shown in Figure 1. As shown in the magnified SEM image in Figure 1, it was confirmed that the bonding was good, with no voids or cracks in the bonding interface or bonding layer.

[0053] Examples 2-4 Three types of sheet-like sintered bonding materials were prepared in the same manner as in Example 1, except that the thickness of bonding layer 1 and bonding layer 2 after drying was changed as shown in Table 2.

[0054] Next, test pieces A and B were temporarily joined to the test pieces A and B in the same manner as described in Test Example 1, except that the sheet-like sintered bonding material obtained in Examples 2 to 4 was used. For the three types of temporary joints obtained, even when test piece B was held with test piece A facing downwards and gently shaken up and down and side to side, the joint remained intact and test piece A did not peel off or fall. This confirmed that all of the sheet-like sintered bonding materials obtained in Examples 2 to 4 possess tack properties.

[0055] The three types of temporary joints described above were joined using a firing apparatus (upper and lower pulse heat unit joining apparatus) manufactured by Japan Avionics Co., Ltd., in the same manner as in Test Example 3, at a temperature of 300°C, a pressure of 10 MPa, a joining time of 180 seconds, and a holding time of 150 seconds. An arbitrary portion of the obtained sheet-like joint was selected and cut out as a No. 2 shear test specimen in accordance with JIS Z 3198-5. The shear strength was measured using an A&D TENSILON strength tester, and the average value was calculated. The results are shown in Table 2.

[0056] [Table 2]

[0057] As shown in Table 2, when the thickness of adhesive layer 1 and adhesive layer 2 after drying in the sheet-like sintered bonding material is 20 μm or more, as in Examples 2 to 4, there is no significant change in bonding strength even if there is a difference in thickness between adhesive layer 1 and adhesive layer 2, and a sufficient bonding strength of 10 MPa or more is achieved in both cases.

[0058] From the above, it can be seen that even if the thickness of each adhesive layer on both sides of a sheet-like sintered bonding material is changed, there is no significant change in tackiness, preventing defects due to "misalignment," and since the bonded members do not move during the process, productivity such as handling and yield can be improved. Moreover, even if the thickness of the bonded layers varies, a certain level of bonding strength can be obtained, making it possible to efficiently manufacture electrical equipment, electronic equipment, semiconductor components, heat dissipation components, etc., with the desired performance.

Claims

1. A metal layer consisting of a plate-shaped or foil-shaped metal, The metal layer has a tacky adhesive layer on both sides containing metal nanoparticles and a solvent. The aforementioned solvent contains one or more polyols as high viscosity solvents, including isobornylcyclohexanol, terpenes (Tersolve THA90 (trade name)), triethanolamine, polyethylene glycol, styrene-acrylonitrile copolymer, or fine particles of polyurea. A sheet-like sintered bonding material characterized in that the metal nanoparticles are composite metal nanoparticles in which an organic coating layer made of one or more aliphatic carboxylic acids having 1 to 10 or 12 carbon atoms is formed around a metal nucleus with an average particle size of 1 to 200 nm, which is made up of an aggregate of metal atoms.

2. The sheet-like sintered bonding material according to claim 1, wherein the content of the highly viscous solvent in the adhesive layer is 0.1 to 20.0% by mass.

3. The sheet-like sintered bonding material according to claim 1 or 2, wherein the thickness of the metal layer is 10 to 1000 μm and the thickness of the adhesive layer is 20 to 100 μm.

4. The sheet-like sintered bonding material according to claim 1 or 2, wherein the metal atoms constituting the metal nanoparticles are individual metals consisting of copper, gold, platinum, palladium, or silver, or composites thereof.

5. The sheet-like sintered bonding material according to claim 1 or 2, wherein the adhesive layers on both sides of the metal layer allow the bonding member to be fixed after being mounted to the sheet-like sintered bonding material.

6. The sheet-like sintered bonding material according to claim 1 or 2, wherein the adhesive layer comprises metal nanoparticles, a filler, a solvent, and a dispersant.

7. The sheet-like sintered bonding material according to claim 1 or 2, wherein one or both sides of the metal layer are surface-treated with one or more of a metal selected from the group consisting of copper, gold, silver, platinum, or palladium, or a composite thereof.

8. A joint formed by joining a sheet-like sintered bonding material and a bonding member according to claim 1 or 2, or an electrical device, electronic device, semiconductor component, or heat dissipation component in which such joint is used.

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