Method for manufacturing conjugant

Abstract

To provide a method for manufacturing a conjugant configured by bonding conductive components together via a conductive joint portion, the method including a step of heating and pressurizing a laminate configured by stacking the conductive components together via a joint material, and enabling a conjugant to be manufactured in a shorter time than before.SOLUTION: A method for manufacturing a conjugant 1 includes a placement step of placing a laminate 101 between a pair of heating and pressurizing means 9, and a firing step of heating and pressurizing the laminate 101 with the heating and pressurizing means 9 to fire the conjugant material 130, thereby forming a conductive conjugant portion 13. In the placement step, the temperature of the heating and pressurizing means 9 is set so as to be capable of firing the conjugant material 130, a thermally conductive elastic body 8 is placed on the surface of one of the heating and pressurizing means 91, and the laminate 101 is placed on the end portion of the elastic body 8 in a non-contact manner with the other heating and pressurizing means 92. In the firing step, by reducing the distance between the laminate 101 and the heating and pressurizing means 9 the laminate 101 is pressurized and heated while the temperature of the heating and pressurizing means 9 set high enough to fire the conjugant material 130.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a method for producing a bonded body. [Background technology]

[0002] When electrically conductive parts are bonded to each other, a bonding material containing metal particles is sometimes used. By heating and sintering such a bonding material, the metal particles are sintered to form a metal sintered body, which becomes an electrically conductive bonding part. By using such a method, for example, a semiconductor chip having a metal thin film and a substrate can be bonded well.

[0003] More specifically, when a bonding material is used, a laminate is produced in which conductive parts are stacked together via a dried bonding material that has been dried without being fired, and this laminate is then sandwiched between a pair of heating and pressing means and pressurized while being heated to fire the bonding material, thereby producing a bonded body in which the conductive parts are joined together at conductive joints.

[0004] In this case, if the sintering of the bonding material (sintering of the metal particles) proceeds before the pressurization of the laminate, the compression of the metal particles becomes insufficient, and a joint with many voids is formed. Since the strength of the joint with many voids and not dense is insufficient, the bonding strength between the conductive parts in the resulting joint is insufficient. Furthermore, if heating and cooling are repeatedly performed on the joint with many voids, cracks will occur in the joint, and the reliability of the joint will be insufficient. Therefore, in order to solve such problems, it is common to sandwich the laminate between a pair of heating and pressing means, pressurize it, and then start heating. However, when this method is adopted, there is another problem that it takes a long time to heat the heating and pressing means by heating in order to sinter the bonding material in the laminate after pressing the laminate.

[0005] As a manufacturing method of a bonded body that can solve these problems, a manufacturing method has been disclosed in which a laminate is held by an arm and placed between a pair of heating and pressing means without contacting the heating and pressing means. More specifically, in this manufacturing method, the temperature of the heating and pressing means is set to a temperature at which the bonding material can be fired, and the laminate is placed between the heating and pressing means by an arm, heating of the laminate is started, one heating and pressing means is brought into contact with the laminate, the arm is removed, and the operations up to this point are performed before the bonding material is fired, and then the other heating and pressing means is also brought into contact with the laminate, and the bonding material is fired by heating and pressing the laminate with the pair of heating and pressing means (see Patent Document 1). Also disclosed is a manufacturing method in which a box-shaped pressing unit is used instead of an arm, and the laminate to which the pressing unit is attached is placed between a pair of heating and pressing means without contacting the heating and pressing means (see Patent Document 1). More specifically, in this manufacturing method, the temperature of the heating and pressurizing means is set to a temperature at which the bonding material can be fired, and a laminate equipped with a pressurizing unit is placed between the heating and pressurizing means to begin heating of the laminate. Next, the pair of heating and pressurizing means heats and pressurizes the laminate together with the pressurizing unit to fire the bonding material, thereby producing a bonded body. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 6129351 Summary of the Invention [Problem to be solved by the invention]

[0007] However, among the manufacturing methods described in Patent Document 1, the manufacturing method using an arm has a problem that the arm cannot stably hold a thin laminate, and if the laminate falls during transportation, it takes time to recover, making it impossible to manufacture a bonded body in a short time. And, in the manufacturing method using a pressure unit, the heat capacity of the pressure unit is relatively large, so even if the temperature of the heating and pressing means is set in advance to a temperature at which the bonding material can be fired, it takes time to raise the temperature of the bonding material, making it impossible to manufacture a bonded body in a short time.

[0008] The present invention provides a method for manufacturing a bonded body formed by bonding conductive parts together via a conductive joint, which includes a step of heating and pressurizing a laminate formed by stacking conductive parts together via a bonding material, and has an objective of providing a method for manufacturing a bonded body that can produce a bonded body in a shorter time than conventional methods. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention employs the following configuration. [1] A method for manufacturing a bonded body, the bonded body being configured by bonding a conductive first part and a conductive second part via a conductive bonding part, the method comprising: a step of arranging a laminate configured by stacking the conductive first part, a bonding material, and the conductive second part in this order in a thickness direction between a pair of heating and pressing means; and a step of heating and pressing the laminate while applying pressure to the heating and pressing means to sinter the bonding material and form the bond from the bonding material, wherein in the step of arranging, a temperature of the pair of heating and pressing means is adjusted to a temperature capable of sintering the bonding material, and one of the front heating and pressing means is heated and pressed to a temperature capable of sintering the bonding material. A thermally conductive elastic body that is stretchable in the direction connecting the pair of heating and pressing means is arranged on the surface of the other heating and pressing means side of the heating and pressing means, and the laminate is placed on the other part of the elastic body on the heating and pressing means side without contacting the other heating and pressing means, thereby arranging the laminate between the pair of heating and pressing means, and in the firing process, while maintaining the temperature of the pair of heating and pressing means at a temperature at which the bonding material can be fired, the distance between the pair of heating and pressing means is narrowed, thereby bringing the other heating and pressing means into contact with the laminate, and heating and pressing the laminate.

[0010] [2] The method for producing a bonded body according to [1], wherein the elastic body is a coil having a conical, pyramidal, truncated conical or truncated pyramidal shape. [3] The method for manufacturing a bonded body according to [1] or [2], wherein one or both of a temperature at which the bonding material can be fired in the placing step and a temperature at which the bonding material can be fired in the firing step are 180° C. or higher. [4] The method for producing a bonded body according to any one of [1] to [3], wherein the arrangement step and the firing step are repeated two or more times to continuously produce two or more of the bonded bodies. Effect of the Invention

[0011] According to the present invention, there is provided a method for manufacturing a bonded body formed by bonding conductive parts together via a conductive joint, which includes a step of heating and pressurizing a laminate formed by stacking the conductive parts together via a bonding material, and which can produce a bonded body in a shorter time than conventional methods. [Brief description of the drawings]

[0012] [Figure 1] 1 is a cross-sectional view showing a schematic example of a bonded body to which a manufacturing method according to an embodiment of the present invention is applied; [Diagram 2] 1A to 1C are cross-sectional views for illustrating an example of a method for producing a bonded body according to an embodiment of the present invention. [Diagram 3] 1A to 1C are cross-sectional views for illustrating a schematic example of a method for producing a laminate used in producing a bonded body. [Figure 4] FIG. 2 is an enlarged front view showing an elastic body used in a method for producing a bonded body according to an embodiment of the present invention. [Diagram 5] 1 is a graph showing temperature histories during heating and pressurization of test laminates in Test Examples 1 and 2. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] ◇ Manufacturing method of the joint A method for producing a bonded body according to one embodiment of the present invention is a method for producing a bonded body in which a conductive first part (sometimes simply referred to as a "first part" in this specification) and a conductive second part (sometimes simply referred to as a "second part" in this specification) are bonded to each other via a conductive bonding part (sometimes simply referred to as a "bonding part" in this specification), the method comprising: a positioning step of positioning a laminate in which the conductive first part, a bonding material, and the conductive second part are laminated in this order in a thickness direction between a pair of heating and pressing means; and a firing step of heating and pressing the laminate with the heating and pressing means to fire the bonding material and form the bonding part from the bonding material, and in the positioning step The temperature of the pair of heating and pressing means is adjusted to a temperature at which the bonding material can be fired, and a thermally conductive elastic body (sometimes simply referred to as an "elastic body" in this specification) that is stretchable in the direction connecting the pair of heating and pressing means is arranged on the surface of one of the heating and pressing means facing the other heating and pressing means, and the laminate is placed on the portion of the elastic body facing the other heating and pressing means without contacting the other heating and pressing means, thereby placing the laminate between the pair of heating and pressing means, and in the firing process, while maintaining the temperature of the pair of heating and pressing means at a temperature at which the bonding material can be fired, the distance between the pair of heating and pressing means is narrowed, so that the other heating and pressing means is brought into contact with the laminate to heat and pressurize the laminate.

[0014] In the manufacturing method of the present embodiment, in the arrangement step, the temperature of the pair of heating and pressing means is set to a temperature at which the bonding material can be sintered, and the laminate is arranged between these heating and pressing means without contacting these heating and pressing means, and heating of the laminate is started, so that the sintering of the bonding material (sintering of metal particles) does not proceed beyond the pressurization of the laminate. As a result, the occurrence of voids is suppressed in the bonded portion in the finally obtained bonded body, so that a dense bonded portion is formed and the strength of the bonded portion is sufficiently high. In the obtained bonded body, the bonding strength between the first part and the second part is also sufficiently high. Furthermore, since the bonded portion is dense, even if the bonded body is repeatedly heated and cooled, the occurrence of cracks in the bonded portion is suppressed, and the reliability of the bonded body is sufficiently high.

[0015] Furthermore, in the arrangement step, by setting the temperature of the heating and pressing means to a temperature at which the bonding material can be fired before the arrangement of the laminate, the bonding material in the laminate can be fired in a short time when the firing step is subsequently performed. In the arrangement step, a thermally conductive elastic body is arranged on the surface of one of the heating and pressing means on the other side of the heating and pressing means, the laminate is placed on the other part of the elastic body on the side of the heating and pressing means, and the firing step is subsequently performed, so that even a thin laminate can be stably held on the elastic body, and unlike a box-shaped pressing unit, the elastic body can be heated in a short time, so that the bonding material in the laminate can be fired in a short time in this respect as well.

[0016] Hereinafter, the method for producing the bonded body of the present embodiment will be described with reference to the drawings. In addition, the figures used in the following explanation may show key parts enlarged for convenience in order to make the features of the present invention easier to understand, and the dimensional ratios of each component may not necessarily be the same as the actual ones. First, a bonded body to which the manufacturing method of this embodiment is applied will be described.

[0017] <<zygote>> FIG. 1 is a cross-sectional view showing a schematic example of the bonded body. The bonded body 1 shown here is configured by bonding a conductive first component 11 and a conductive second component 12 via a conductive bonding portion 13. The first component 11 is in contact with the joint portion 13 on one surface 11a thereof. The second component 12 is in contact with the joint portion 13 at one surface 12a thereof. The bonded body 1 is configured by laminating a first component 11, a bonding portion 13, and a second component 12 in this order in the thickness direction.

[0018] The area of ​​one surface 11 a of the first component 11 is equal to or larger than the area of ​​one surface 12 a of the second component 12 .

[0019] The first component 11 has a sheet, plate or block shape.

[0020] The first component 11 is preferably configured to contain a metal, and more preferably is made of metal. The metal constituting the first component 11 may be either an elemental metal or an alloy. Preferred examples of the metal include copper, silver, gold, palladium, nickel, aluminum, and alloys containing one or more selected from the group consisting of copper, silver, gold, palladium, nickel, and aluminum. Among these, the metal is more preferably copper, silver, gold, palladium, or nickel, and even more preferably copper or silver.

[0021] The first component 11 may be made of one layer (single layer) or may be made of two or more layers. When the first component 11 is made of multiple layers, these multiple layers may be the same or different from each other, and the combination of these multiple layers is not particularly limited. In this specification, not only in the case of the first part, "multiple layers may be the same or different" means "all layers may be the same, all layers may be different, or only some layers may be the same", and further, "multiple layers are different" means "at least one of the constituent materials and thicknesses of each layer is different from each other".

[0022] When the first component 11 is made up of a plurality of layers, for example, one or more layers on the bonding portion 13 side of the first component 11 may be layers that improve adhesion to the bonding portion 13 . The first component 11 made of multiple layers may be, for example, a metal member having one or more metal layers further provided on the surface thereof. The metal layer can be formed on the surface of the object by a known method such as vapor deposition or plating.

[0023] The thickness of the first component 11 can be set arbitrarily depending on the purpose of the joined body 1, and is not particularly limited. The thickness of the first component 11 may be, for example, 10 to 10,000 μm.

[0024] When the first component 11 is made up of a plurality of layers, the total thickness of the layers is preferably the thickness of the first component 11 described above.

[0025] Here, the first part 11 is shown to be in a sheet shape, a plate shape, or a block shape, but the first part 11 may be in a shape other than these, and the shape of the first part 11 can be selected arbitrarily depending on the purpose.

[0026] The second part 12 has a sheet, plate or block shape.

[0027] The second component 12 is preferably composed of a metal, and more preferably made of metal, and examples of metals constituting the second component 12 include the same metals as those constituting the first component 11 described above.

[0028] The second component 12 may be made of one layer (single layer) or may be made of two or more layers. When the second component 12 is made of multiple layers, these multiple layers may be the same or different from each other, and the combination of these multiple layers is not particularly limited.

[0029] When the second component 12 is made up of multiple layers, for example, one or more layers on the bonding portion 13 side of the second component 12 may be layers that improve adhesion to the bonding portion 13. The second part 12 made of multiple layers may be, for example, similar to the first part 11 made of multiple layers described above, and such second part 12 is obtained in the same manner as the first part 11 made of multiple layers.

[0030] The joined body 1 may include a composite of a metal member and a non-metal member as a component including the second component 12. That is, the second component 12 made of metal (a metal member) may form a composite with the non-metal member. In that case, the second component 12 made of metal may be, for example, a layer that improves adhesion with the joint 13, or may be an electrode.

[0031] Examples of the non-metallic member include a semiconductor wafer, a semiconductor chip, an organic insulating substrate, an inorganic insulating substrate, and an organic-inorganic composite insulating substrate, and these may be publicly known.

[0032] Examples of the semiconductor wafer or semiconductor chip include wafers or chips made of semiconductors such as silicon, silicon carbide, or gallium nitride. Examples of the organic insulating substrate include a polytetrafluoroethylene (PTFE) substrate, a polyimide substrate, a liquid crystal polymer substrate, and a cycloolefin polymer substrate. The inorganic insulating substrate may be, for example, a ceramic substrate. The organic-inorganic composite insulating substrate is a substrate containing both organic and inorganic materials as constituent materials, and an example thereof is a substrate made of glass epoxy resin.

[0033] Regardless of the type of non-metallic component, the composite can be produced, for example, by forming a metallic component at a desired location on the non-metallic component by vapor deposition, plating, sputtering, printing, or the like, or by joining the metallic component by brazing or bonding with an adhesive, or the like.

[0034] The thickness of the second component 12 can be set arbitrarily depending on the purpose of the joined body 1, and is not particularly limited. The thickness of the second component 12 is preferably 0.05 to 10,000 μm and may be, for example, 0.05 to 500 μm, or may be more than 500 μm and not more than 10,000 μm. For example, when the metallic second component 12 forms a composite body with a non-metallic member, the thickness of the metallic second component 12 is preferably 0.05 to 10 μm. When the second component 12 is made up of a plurality of layers, the total thickness of the layers is preferably the thickness of the second component 12 described above.

[0035] When the metallic second component 12 forms a complex with a non-metallic member, the thickness of the non-metallic member may be, for example, 500 to 10,000 μm.

[0036] The area of ​​one surface 11a of the first component 11 is preferably equal to or larger than the area of ​​one surface 12a of the second component 12.

[0037] Here, the second part 12 is shown to be in a sheet shape, a plate shape, or a block shape, but the second part 12 may be in a shape other than these, and the shape of the second part 12 can be selected arbitrarily depending on the purpose.

[0038] The joint 13 is in the form of a sheet, a plate or a block. The bonding portion 13 may be made of one layer (single layer) or may be made of two or more layers. When the bonding portion 13 is made of multiple layers, these multiple layers may be the same or different from each other, and the combination of these multiple layers is not particularly limited.

[0039] It is preferable that the entire surface of the joint portion 13 on the first component 11 side be in contact with one surface 11 a of the first component 11 .

[0040] The thickness of the joint 13 may be, for example, 10 μm or more and less than 90 μm, or may be any of 90 μm or more, 150 μm or more, and 300 μm or more. The greater the thickness of the joint 13, the higher the strength of the joint 13. On the other hand, the thickness of the joint 13 is preferably 400 μm or less in that the joint 13 can be formed more easily.

[0041] Here, the joint 13 is shown to be in a sheet, plate or block shape, but the joint 13 may be in any other shape, and the shape of the joint 13 can be selected arbitrarily depending on the purpose.

[0042] The area of ​​the contact region of the joint 13 with the first component 11 (more specifically, one surface 11a) and the area of ​​the contact region with the second component 12 (more specifically, one surface 12a) may be the same or different, and may be within a range of 4 to 400 mm 2 It is preferable that the thickness is 9 to 100 mm. 2 More preferably, for example, 9 to 64 mm 2 , and 9 to 36 mm 2 It may be any one of 16 to 100 mm 2 , and 49 to 100 mm 2 It may be either 16 to 64 mm 2 However, these are just examples of the area of ​​the contact region.

[0043] The area of ​​one surface 12a of the second component 12 is preferably 50 to 150% of the area of ​​the surface of the joint 13 on the second component 12 side. The area of ​​the contact region with the joint portion 13 on one surface 12a of the second component 12 is preferably 50 to 100% of the entire area of ​​the one surface 12a. In joint 13, it is preferable that the entire surface on the first component 11 side is in contact with first component 11.

[0044] In the joined body 1, one first component 11 and one second component 12 are joined by one joint 13, but the joining form is not limited to this. In the joined body, for example, one first part and two or more second parts may be joined by one joint, in which case the two or more second parts may all be the same, all be different, or only partly different. In addition, in the joined body, for example, one first part and two or more second parts may be joined by two or more joining parts. In this case, the number of second parts and the number of joining parts may be the same or different. Furthermore, the two or more second parts may all be the same, all be different, or only some may be different. The numbers of first components and second components exemplified here may be reversed.

[0045] The bonded body to which the manufacturing method of the present embodiment is applied is not limited to that shown in FIG. 1. For example, the bonded body 1 shown in FIG. 1 may have some components changed, deleted, or added thereto without departing from the spirit of the present invention. Next, the manufacturing method of this embodiment will be described by taking as an example the case of manufacturing the bonded body shown in FIG.

[0046] FIG. 2 is a cross-sectional view for illustrating a schematic example of a method for producing a bonded body according to the present embodiment. In FIG. 2 and subsequent figures, the same components as those shown in the figures already described are given the same reference numerals as in the figures already described, and detailed description thereof will be omitted.

[0047] <<Placement process>> In the arrangement step, a laminate 101 is used, which is configured by laminating a first component 11, a bonding material 130, and a second component 12 in this order in the thickness direction, as shown in FIG. 2(a). In this specification, unless otherwise specified, the term "laminate" refers to such a laminate of a first component, a bonding material, and a second component.

[0048] The laminate 101 can be produced, for example, by providing a bonding material 130 on one or both of one surface 11a of the first component 11 and one surface 12a of the second component 12, and then superimposing the remaining components for forming the laminate 101 on the exposed surface of the bonding material 130 (the surface opposite to the side of the first component 11 or the second component 12).

[0049] More specifically, when the bonding material 130 is provided only on one surface 11a of the first component 11, the laminate 101 can be produced by overlapping one surface 12a of the second component 12 on the exposed surface of the bonding material 130. When the bonding material 130 is provided only on one surface 12a of the second component 12, the layered body 101 can be produced by overlapping one surface 11a of the first component 11 on the exposed surface of the bonding material 130. When bonding material 130 is provided on both one surface 11a of first component 11 and one surface 12a of second component 12, laminate 101 can be produced by overlapping the exposed surfaces of these bonding materials 130 together.

[0050] FIG. 3 is a cross-sectional view for illustrating a schematic example of a method for producing a laminate, and shows a method for producing a laminate in which a bonding material 130 is provided only on one surface 11a of the first component 11. That is, in this case, as shown in Figures 3(a) and 3(b), a bonding material 130 is provided on one surface 11a of the first component 11. Next, as shown in Figure 3(c), one surface 12a of the second component 12 is laid on the exposed surface of the bonding material 130. In this way, a laminate 101 is obtained.

[0051] The bonding material 130 can be provided on one surface 11a of the first component 11 or one surface 12a of the second component 12 by a known method. The method of providing the bonding material 130 can be arbitrarily selected depending on the type of bonding material 130. For example, when the bonding material 130 is a liquid bonding material containing silver particles, which will be described later, known printing methods, coating methods, and the like can be used. In this specification, the process of providing the bonding material to the object when such a liquid bonding material is used may be referred to as the "attachment process."

[0052] Examples of the printing method include screen printing, flexographic printing, offset printing, dip printing, inkjet printing, dispenser printing, jet dispenser printing, gravure printing, gravure offset printing, pad printing, etc. In this specification, the bonding material provided by the printing method may be referred to as a "printed layer".

[0053] Examples of the coating method include methods using various coaters such as a spin coater, an air knife coater, a curtain coater, a die coater, a blade coater, a roll coater, a gate roll coater, a bar coater, a rod coater, and a gravure coater; methods using a wire bar; and methods using a coating device such as a slot die.

[0054] When the bonding material 130 provided on one surface 11a of the first component 11 or one surface 12a of the second component 12 is liquid, the bonding material 130 in the laminate 101 may remain in an undried liquid state, but is preferably dried to a solid state (dried bonding material). In this specification, the process of drying a liquid bonding material to a solid state is sometimes referred to as a "pre-drying process."

[0055] The laminate 101, which is a laminate of the first component 11, a solid bonding material (dried bonding material) 130, and the second component 12, is formed, for example, by a step (adhering step) of providing the liquid bonding material 130 on one or both of the first surface 11a of the first component 11 and the first surface 12a of the second component 12, and by superposing the remaining components for forming the laminate 101 on the exposed surface of the bonding material 130 after the adhering step, thereby forming a laminate provided with the liquid bonding material 130 (in this specification, a laminate provided with a dried bonding material). The bonding material 130 can be prepared by a method (sometimes referred to as "lamination method (i)" herein) having a step of preparing a laminate (sometimes referred to as "undried laminate" to distinguish it from the laminate) (sometimes referred to as "lamination step (i)" herein), and a step of drying the liquid bonding material 130 in the laminate (undried laminate) to solidify it after the lamination step (i) (sometimes referred to as "pre-drying step (i)" herein). In the method of producing the laminate described with reference to FIG. 3, the laminate 101 shown in FIG. 3(c) is produced in which the bonding material 130 is liquid, and then, in the laminate 101 in this state, the liquid bonding material 130 is dried to produce the laminate 101 having the bonding material (dried bonding material) 130 in a solid state.

[0056] Furthermore, the laminate 101, which is a laminate of the first component 11, the solid bonding material (dried bonding material) 130, and the second component 12, can also be produced by a method including a step of providing the liquid bonding material 130 on one or both of one surface 11a of the first component 11 and one surface 12a of the second component 12 (an adhesion step), a step of drying the liquid bonding material 130 to form a solid form after the adhesion step (this pre-drying step may be particularly referred to as a “pre-drying step (ii)” in this specification), and a step of producing a laminate including the solid bonding material 130 by superposing the remaining components for forming the laminate 101 on the exposed surface of the solid bonding material (dried bonding material) 130 after the pre-drying step (ii) (this step may be referred to as a “superposing step (ii)” in this specification). In the method for producing the laminate described with reference to FIG. 3, in a laminate of a first component 11 and liquid bonding material 130 shown in FIG. 3(b), the liquid bonding material 130 is dried, and then a second component 12 is superimposed on the exposed surface of the solid bonding material (dried bonding material) 130, thereby producing a laminate 101 including a solid bonding material (dried bonding material) 130.

[0057] In the disposing step, as shown in FIG. 2( b ), the laminate 101 is disposed between a pair of heating and pressing means 9 , that is, one heating and pressing means 91 and the other heating and pressing means 92 . More specifically, in the arrangement step, the temperature of the pair of heating and pressing means 9 (one heating and pressing means 91 and the other heating and pressing means 92) is adjusted to a temperature capable of firing the bonding material 130 in the laminate 101. The bonding material 130 may be in either a liquid state or a solid state (dried), and is preferably in a solid state.

[0058] One heating and pressing means 91 is movable in a direction connecting it and the other heating and pressing means 92, and can both approach the other heating and pressing means 92 and move away from the other heating and pressing means 92. By one heating and pressing means 91 approaching the other heating and pressing means 92, the laminate 101 can be pressed by one heating and pressing means 91. Similarly, the other heating and pressing means 92 is movable in a direction connecting it and the one heating and pressing means 91, and can both approach one heating and pressing means 91 and move away from one heating and pressing means 91. By the other heating and pressing means 92 approaching one heating and pressing means 91, the laminate 101 can be pressed by the other heating and pressing means 92.

[0059] In this specification, "pressurization" means increasing the pressure applied to an object by actively applying force to the object, and does not mean, for example, that the object is only supported (just applying normal force) and no operation of actively applying force is performed. In the case of pressurization, for example, the position of the pressurizing means changes by itself with acceleration.

[0060] One heating and pressurizing means 91 and the other heating and pressurizing means 92 are not particularly limited and may be any known means as long as they are themselves heatable and can pressurize an object while heating it by sandwiching the object between them. The one heating and pressing means 91 and the other heating and pressing means 92 may be, for example, a heating press plate.

[0061] In the placement process, the temperature of the pair of heating and pressing means 9 (one heating and pressing means 91 and the other heating and pressing means 92) is not particularly limited as long as it is a temperature at which the bonding material 130 can be fired, and can be appropriately adjusted, for example, depending on the type of bonding material 130. Generally, the temperature of the pair of heating and pressurizing means 9 is preferably 180° C. or higher, and may be, for example, any one of 200° C. or higher, 240° C. or higher, and 280° C. or higher. The higher the temperature of the pair of heating and pressurizing means 9, the more quickly the bonding material 130 is heated. Then, in the firing step described later, the bonding material 130 is fired more quickly. On the other hand, the temperature of the pair of heating and pressing means 9 is preferably equal to or lower than 320° C. The lower the temperature of the pair of heating and pressing means 9, the greater the effect of suppressing the burning of the bonding material 130 in the arranging step.

[0062] In the placement process, as shown in FIG. 2(b), a thermally conductive elastic body 8 that is stretchable in the direction connecting the pair of heating and pressurizing means 9 is placed on the surface 91a of one heating and pressurizing means 91 facing the other heating and pressurizing means 92. In FIG. 2(b), the cross-sectional view of the elastic body 8 is omitted, and this also applies to the subsequent figures.

[0063] Three elastic bodies 8 are arranged on the surface 91a of one of the heating and pressing means 91 so that the three elastic bodies 8 form the vertices of a triangle. In this case, the triangle may be an equilateral triangle or an isosceles triangle.

[0064] The elastic body 8 is a spring, and more specifically, a coil having a truncated cone shape. Of the elastic bodies 8, the end 8a on the large outer diameter side is in contact with one of the heating and pressing means 91, and the end 8b on the small outer diameter side is in contact with the laminate 101 (more specifically, the first component 11). This is common to all three elastic bodies 8. It is preferable that all three elastic bodies 8 are the same.

[0065] 2(b), in the placement step, the laminate 101 is placed on a portion of the elastic body 8 facing the other heating and pressing means 92 without contacting the other heating and pressing means 92. Here, the portion of the elastic body 8 facing the other heating and pressing means 92 refers to an end portion 8b of the elastic body 8 on the small outer diameter side. The laminate 101 is placed with the first component 11 in contact with the elastic body 8 and the second component 12 facing the other heating and pressing means 92 without contacting the other heating and pressing means 92.

[0066] In this way, by placing the laminate 101 on the elastic bodies 8, the lengths of all three elastic bodies 8 become uniformly shorter than the free length (the length of the elastic bodies 8 in the stretchable direction when nothing is placed on the elastic bodies 8) due to the pressure from the laminate 101. Here, "the stretchable direction of the elastic bodies 8" is synonymous with "the central axial direction of the elastic bodies 8" and "the direction connecting one heating and pressing means 91 and the other heating and pressing means 92."

[0067] In the arrangement step, the laminate 101 is arranged between a pair of heating and pressing means 9 (one heating and pressing means 91 and the other heating and pressing means 92) as described above. Then, since the pair of heating and pressing means 9 are heated, the laminate 101 is heated by these heating and pressing means 9. However, the laminate 101 is placed on the elastic body 8 without contacting one heating and pressing means 91, and is arranged without contacting the other heating and pressing means 92. Therefore, even if the temperature of the pair of heating and pressing means 9 is adjusted to a temperature at which the bonding material 130 in the laminate 101 can be fired, the bonding material 130 is heated, but the firing of the bonding material 130 is suppressed from the start of heating. That is, in the arrangement step, the heating of the bonding material 130 at a high temperature is immediately started, but the firing of the bonding material 130 is suppressed.

[0068] In the arrangement step, the distance L1 between the bonding material 130 and one of the heating and pressing means 91 (the distance between the surface 130b of the bonding material 130 on the first component 11 side and the surface 91a of one of the heating and pressing means 91 on the other heating and pressing means 92 side) is preferably 1 to 100 mm, and more preferably 3 to 30 mm. When L1 is equal to or greater than the lower limit, the effect of suppressing the sintering of the bonding material 130 in the arrangement step is enhanced. When L1 is equal to or less than the upper limit, the bonding material 130 is heated more quickly.

[0069] In the arrangement step, the distance L2 between the bonding material 130 and the other heating and pressing means 92 (the distance between the surface 130a of the bonding material 130 on the second component 12 side and the surface 92a of the other heating and pressing means 92 on the one heating and pressing means 91 side) is preferably 50 to 500 mm, and more preferably 100 to 300 mm. When L2 is equal to or greater than the lower limit, the effect of suppressing the sintering of the bonding material 130 in the arrangement step is enhanced. When L2 is equal to or less than the upper limit, the bonding material 130 is heated more quickly.

[0070] FIG. 4 is an enlarged front view of the elastic body 8. As shown in FIG. The large outer diameter D1 of the elastic body 8 (the diameter of the elastic body 8 at the end 8a on the large outer diameter side) is preferably 0.5 to 70 mm, and more preferably 2 to 20 mm. When D1 is equal to or greater than the lower limit, the laminate 101 can be more stably placed on the elastic body 8. When D1 is equal to or less than the upper limit, the elastic body 8 can be prevented from being excessively large.

[0071] The small outer diameter D2 of the elastic body 8 (the diameter of the elastic body 8 at the end 8b on the small outer diameter side) is preferably 0.25 to 30 mm, and more preferably 0.5 to 10 mm. When D2 is in this range, the effect of the elastic body 8 having a truncated cone shape is enhanced.

[0072] The free length H1 of the elastic body 8 (the length of the elastic body 8 in the stretchable direction when the elastic body 8 is placed on a flat surface with nothing placed on the elastic body 8) is preferably 0.5 to 100 mm, and more preferably 4 to 50 mm. If H1 is in such a range, it becomes easier to adjust L1.

[0073] The wire diameter of the wire constituting the elastic body 8 is not particularly limited as long as the thermal conductivity and elastic modulus of the elastic body 8 described below fall within the desired ranges. For example, the wire diameter of the wire is preferably 0.01 to 10 mm, and may be any of 0.01 to 1 mm and 1 to 10 mm.

[0074] Here, a truncated cone-shaped coil, which is a type of spring, is shown as the elastic body 8, but the elastic body used in the placement step may have other shapes. Examples of the coil-shaped elastic body 8 having a shape other than a truncated cone include a coil having a cone shape, a pyramid shape, and a truncated pyramid shape.

[0075] An example of the conical coil is a coil that is the same as the above-mentioned truncated conical coil, except that the small outer diameter (small outer diameter D2 in FIG. 4) is 0 mm or more and less than 0.25 mm.

[0076] Examples of coils having a truncated pyramid shape include, but are not limited to, coils having a triangular pyramid shape, a square pyramid shape, and a pentagonal pyramid shape. When a coil having a truncated pyramid shape is viewed from the large outer diameter side in plan view, the area of ​​the largest area surrounded by the wire constituting the coil (in other words, the area corresponding to the base of the truncated pyramid) is 100 to 1000 mm 2 It is preferable that: When a coil having a truncated pyramid shape is viewed from the small outer diameter side, the area of ​​the area surrounded by a single continuous wire that constitutes the coil and that has the smallest area (in other words, the area corresponding to the top surface of the truncated pyramid) is 5 to 200 mm 2 It is preferable that: The free length of the truncated pyramidal coil is preferably the same as the free length of the truncated conical coil. The wire diameter of the wire constituting the truncated pyramidal coil is preferably the same as the wire diameter of the wire constituting the truncated cone shape (elastic body 8 in FIG. 4).

[0077] Examples of pyramidal coils include, but are not limited to, triangular, quadrangular, and pentagonal pyramidal coils. For example, the area of ​​the pyramidal coil is 0 mm 2 More than 5mm 2 An example of such a coil is the same as the truncated pyramidal coil described above, except that it is less than 100 mm.

[0078] The elastic body used in the placement step may have a shape other than a coil. An example of an elastic body having a shape other than a coil is a leaf spring.

[0079] The elastic body used in the placement step is preferably a coil having a conical, pyramidal, truncated conical or truncated pyramidal shape.

[0080] The spring constant of the elastic body (e.g., elastic body 8 shown in FIG. 4) used in the arrangement step is preferably 0.2 N / mm or more, more preferably 0.35 N / mm or more. By making the spring constant equal to or more than the lower limit, the distance between the bonding material and one of the heating and pressing means in the arrangement step (e.g., L1 shown in FIG. 4) can be made greater. On the other hand, the spring constant is preferably 1.0 N / mm or less, and more preferably 0.6 N / mm or less. By setting the spring constant to the upper limit or less, the bonding material 130 can be more easily fired when the bonding material 130 is pressurized and fired in the firing step described later.

[0081] In this specification, unless otherwise specified, the "spring constant" refers to a spring constant derived from the relationship between the load applied to an elastic body and the deflection of the elastic body, measured using a force tester.

[0082] The thermal conductivity of the elastic body used in the arrangement step (for example, elastic body 8 shown in FIG. 4) is preferably 5 W / (m K) or more, and more preferably 10 W / m K or more. When the thermal conductivity is equal to or more than the lower limit, the bonding material 130 can be fired more easily in the firing step described later. On the other hand, the thermal conductivity is preferably 800 W / (m K) or less, and more preferably 500 W / (m K) or less. An elastic body having a thermal conductivity equal to or less than the upper limit can be more easily obtained or produced.

[0083] In this specification, unless otherwise specified, "thermal conductivity" means thermal conductivity measured by a steady-state method.

[0084] The elastic body used in the placement step (for example, the elastic body 8 shown in FIG. 4) is preferably made of a metal. The metal may be either an elemental metal or an alloy. Preferred examples of the elemental metals include copper, silver, and aluminum. A preferred example of the alloy is stainless steel (SUS).

[0085] <<Firing process>> In the firing step, as shown in FIG. 2(c), the laminate 101 is heated and pressurized by a pair of heating and pressing means 9 (one heating and pressing means 91 and the other heating and pressing means 92) to fire the bonding material 130. More specifically, in the firing process, while maintaining the temperature of the pair of heating and pressurizing means 9 at a temperature at which the bonding material 130 can be fired, the distance between the pair of heating and pressurizing means 9 is narrowed, and the other heating and pressurizing means 92 is brought into contact with the laminate 101 to heat and pressurize the laminate 101. In this embodiment, the firing step starts when the other heating and pressurizing means 92 is brought into contact with the laminate 101 to start heating and pressurizing the laminate 101.

[0086] In this embodiment, the time from placing the laminate 101 between the pair of heating and pressing means 9 to starting heating and pressing the laminate 101 by the pair of heating and pressing means 9 (starting the firing process) is preferably 600 seconds or less, and more preferably 180 seconds or less. By setting the time until starting heating and pressing the laminate 101 to the upper limit or less, the effect of suppressing firing of the bonding material 130 before starting heating and pressing the laminate 101 is enhanced. On the other hand, the time from placing the laminate 101 between the pair of heating and pressing means 9 to starting to heat and press the laminate 101 by the pair of heating and pressing means 9 may be 10 seconds or more, taking into consideration workability.

[0087] The laminate 101 can be heated from one heating and pressing means 91 side by both the elastic body 8 in contact with the laminate 101 and the other heating and pressing means 91 not in contact with the laminate 101, and can be pressed by the elastic body 8 (more specifically, the elastic force of the elastic body 8). That is, the elastic body 8 also serves as the heating and pressing means. The laminate 101 can be heated and pressed from the other heating and pressing means 92 side by the other heating and pressing means 92 that is in contact with the laminate 101 .

[0088] In the baking step, when the other heating and pressing means 92 is moved to the side of one heating and pressing means 91 and the laminate 101 is pressed by the other heating and pressing means 92, the laminate 101 is also simultaneously pressed by the elastic body 8. That is, in the baking step, the laminate 101 is pressed only from the side of one heating and pressing means 91, or the laminate 101 is pressed from both the side of one heating and pressing means 91 and the side of the other heating and pressing means 92.

[0089] In the firing step, the distance between the pair of heating and pressing means 9 may be narrowed as long as the length of the three elastic bodies 8 in the central axis direction is not minimized while the other heating and pressing means 92 is in contact with the laminate 101. However, it is preferable to narrow the distance between the pair of heating and pressing means 9 by maximally shortening the length of the three elastic bodies 8 in the central axis direction. In this way, the laminate 101 can be heated and pressed more efficiently. FIG. 2(c) shows a case where the wires constituting the three elastic bodies 8 do not overlap each other in the central axis direction of the elastic bodies 8 in the entire region, and the thickness of the elastic bodies 8 is equivalent to the diameter of the wires when the elastic bodies 8 are maximally shortened, and the distance between the pair of heating and pressing means 9 is narrowed by maximally shortening the length of the elastic bodies 8 in the central axis direction (until the thickness of the elastic bodies 8 is equivalent to the diameter of the wires).

[0090] In the firing process, not only in the case of elastic body 8, but also in the case of an elastic body, it is preferable to use an elastic body whose thickness becomes equivalent to the diameter of the wire when its length in the central axis direction is maximally reduced to its minimum, and it is more preferable to narrow the distance between the pair of heating and pressing means until the thickness of the elastic body becomes equivalent to the diameter of the wire.

[0091] In the firing step, after heating and pressurizing the laminate 101 is started, the pressure applied to the laminate 101 by the pair of heating and pressurizing means 9 gradually increases. The time from the start of heating and pressurizing the laminate 101 until the pressure applied to the laminate 101 reaches its maximum is preferably 45 seconds or less, and may be, for example, 20 seconds or less. By setting the time until the pressure applied to the laminate 101 reaches its maximum to be equal to or less than the upper limit, the bonding material 130 can be fired in a shorter time. On the other hand, the time from when heating and pressurizing of the laminate 101 is started until the pressure applied to the laminate 101 reaches its maximum may be 5 seconds or more, taking workability into consideration.

[0092] In the firing step, the maximum pressure when the laminate 101 is heated and pressurized by the pair of heating and pressurizing means 9 is preferably 20 MPa or less, and may be, for example, 16 MPa or less. When the pressure is equal to or less than the upper limit, damage such as cracking and deformation of the first component 11 or the second component 12 are further suppressed. On the other hand, the pressure when the laminate 101 is heated and pressed is preferably 5 MPa or more, in order to obtain the effect of the pressurization more effectively, for example, by reducing voids in the joints.

[0093] The temperature of the pair of heating and pressing means 9 in the firing step is not particularly limited as long as it is a temperature at which the bonding material 130 can be fired, and may be the same as the temperature of the pair of heating and pressing means 9 in the above-mentioned arrangement step. That is, the temperature of the pair of heating and pressing means 9 in the firing step is preferably 180° C. or higher, and may be, for example, any one of 200° C. or higher, 240° C. or higher, and 280° C. or higher, and the higher the temperature, the more quickly the bonding material 130 is fired. On the other hand, the temperature of the pair of heating and pressing means 9 in the firing step is preferably 320° C. or lower, and the lower the temperature, the more the bonding material 130 can be prevented from being excessively heated.

[0094] The temperature of the pair of heating and pressing means 9 in the firing step may be the same as or different from the temperature of the pair of heating and pressing means 9 in the above-mentioned arrangement step, and if different, may be higher or lower than the temperature of the pair of heating and pressing means 9 in the arrangement step.

[0095] In this embodiment, it is preferable that either or both of the temperature at which the bonding material 130 can be fired in the placement step and the temperature at which the bonding material 130 can be fired in the firing step are 180° C. or higher. In this way, the bonding material 130 is fired more quickly. In order to enhance such effects, it is more preferable that both of the temperature at which the bonding material 130 can be fired in the placement step and the temperature at which the bonding material 130 can be fired in the firing step are 180° C. or higher.

[0096] In the firing step, the total time for heating and pressing the laminate 101 by the pair of heating and pressing means 9 can be appropriately adjusted depending on the heating temperature of the laminate 101 and the like.

[0097] For example, when the pressure applied to the laminate 101 by the pair of heating and pressing means 9 reaches a maximum and the heating and pressing is continued while maintaining this maximum pressure, the time for which the heating and pressing is continued (the time for which the laminate 101 is heated and pressed at the maximum pressure) is preferably 500 seconds or less, and may be, for example, any of 450 seconds or less, 400 seconds or less, and 360 seconds or less. According to the manufacturing method of this embodiment, the time for heating and pressing the bonding material 130 to form a bonded portion can be significantly shortened compared to the conventional manufacturing methods. On the other hand, the time for which the heating and pressurizing is continued (the time for which the laminate 101 is heated and pressurized at the maximum pressure) is preferably 250 seconds or more in order to sufficiently bake the bonding material 130.

[0098] For example, when the pressure applied to the laminate 101 by the pair of heating and pressing means 9 reaches a maximum and then the pressure is varied to continue heating and pressing, the time for heating and pressing the laminate 101 at a pressure of 5 to 20 MPa is preferably 500 seconds or less, and may be, for example, any one of 450 seconds or less, 400 seconds or less, and 360 seconds or less. According to the manufacturing method of this embodiment, the time for heating and pressing the bonding material 130 to form a bonded portion can be significantly shortened compared to the conventional manufacturing methods. On the other hand, the time for which the laminate 101 is heated and pressed at a pressure of 5 to 20 MPa is preferably 250 seconds or more in order to sufficiently bake the bonding material 130.

[0099] In the firing process, the time from when the pair of heating and pressing means 9 starts heating and pressing the laminate 101 to when the temperature of the laminate 101 (in other words, the bonding material 130) reaches its maximum value can be adjusted appropriately depending on other heating and pressing conditions of the laminate 101.

[0100] For example, the time from when the pressure applied to the laminate 101 by the pair of heating and pressing means 9 reaches a maximum until the temperature of the laminate 101 (in other words, the bonding material 130) reaches a maximum value is preferably 150 seconds or less, and may be, for example, any of 120 seconds or less, 90 seconds or less, and 60 seconds or less. According to the manufacturing method of this embodiment, the time required for the temperature of the bonding material 130 to reach a maximum value can be significantly reduced compared to the conventional manufacturing methods. On the other hand, the time from when the pressure applied to the laminate 101 reaches a maximum until the temperature of the laminate 101 reaches a maximum value may be 10 seconds or more, taking into consideration workability.

[0101] In the firing step, the bonding material 130 in the laminate 101 is fired to form a bonding portion 13 from the bonding material 130, as shown in Fig. 2(d). This results in a bonded body 1 in which the first component 11 and the second component 12 are bonded together via the conductive bonding portion 13.

[0102] The porosity of the bonding portion 13 is preferably 15% or less, and more preferably 10% or less. According to this embodiment, the firing of the bonding material 130 (sintering of metal particles) does not proceed beyond the pressurization of the laminate 101, so that the generation of voids is suppressed in the bonding portion 13, the porosity is at a low level as described above, and a dense bonding portion 13 can be formed. There is no particular limit to the lower limit of the porosity of the joint 13. For example, a joint 13 having a porosity of 3% or more can be formed more easily.

[0103] The porosity of any joint, including the joint 13, can be measured by, for example, the method described below. That is, a cross section of the joint is prepared, and the voids in the cross section are identified. The prepared cross section can be further subjected to mechanical polishing and ion milling. The voids can be identified by observing the cross section using, for example, a scanning electron microscope (SEM), and in this case, the voids may be identified by performing image analysis on the image data of the cross section using a binarization process or the like. After identifying the voids, the ratio of the area of ​​the void region to the area of ​​the cross-section of the joint (in other words, the area of ​​the region surrounded by the outline of the joint in the cross-section of the joint, or the sum of the area of ​​the non-void region and the area of ​​the void region in the cross-section of the joint) can be calculated, and this calculated value can be used as the porosity of the joint.

[0104] In this embodiment, after the bonding portion 13 is formed, when the heating and pressure applied to the bonded body 1 manufactured from the laminate 101 is released, the heating and the pressure may be released in either order, or they may be released simultaneously.

[0105] <<Other processes>> The manufacturing method of this embodiment may or may not include other steps that do not fall under either the arrangement step or the firing step, as long as the effects of the present invention are not impaired. The type, number and timing of the other steps can be arbitrarily selected depending on the purpose and are not particularly limited. In this embodiment, it is preferable that there is no other step between the disposing step and the firing step, and that the disposing step and the firing step are carried out continuously.

[0106] <<Modifications of the manufacturing method of the bonded body>> The manufacturing method of the bonded body of this embodiment is not limited to the manufacturing method described above with reference to FIG. 2, and some components may be changed, deleted, or added in the manufacturing method described with reference to FIG. 2 without departing from the spirit of the present invention.

[0107] For example, while Fig. 2 shows a manufacturing method of a bonded body using three elastic bodies 8, the number of elastic bodies used in the manufacturing method of this embodiment is not particularly limited as long as the laminate can be placed on the elastic bodies, and is not limited to three or more. In general, the number of elastic bodies is preferably three to four, in that the laminate can be placed more stably on a smaller number of elastic bodies. In the arrangement step, regardless of the number of elastic bodies, it is preferable that all of the elastic bodies are arranged on one of the heating and pressing means so as to form vertices of a polygon. In this way, the laminate can be more stably placed on the elastic bodies.

[0108] For example, while FIG. 2 shows a manufacturing method for manufacturing the bonded structure 1 shown in FIG.

[0109] For example, in FIG. 2, the manufacturing method is shown in which the other heating and pressing means 92 is brought into direct contact with the laminate 101 in the firing step to heat and pressurize the laminate 101. In the manufacturing method of this embodiment, a thermally conductive sheet may be placed on the exposed surface of the laminate on the other heating and pressing means side (in other words, the surface opposite to the bonding material side of the second component in the laminate) and the other heating and pressing means may be brought into indirect contact with the laminate via the thermally conductive sheet to heat and pressurize the laminate. In this way, the laminate can be heated and pressed while being protected, and further, the laminate can be pressed with high uniformity over its entire area. For the same reason, a thermally conductive sheet may be placed on the exposed surface of the laminate on one heating and pressing means side (in other words, the surface opposite to the bonding material side of the first component in the laminate) to heat and pressurize the laminate by indirectly contacting the elastic body via the thermally conductive sheet.

[0110] The thermal conductivity of the thermally conductive sheet is preferably in the same range as the thermal conductivity of the elastic body (for example, the elastic body 8 shown in FIG. 4). The thermally conductive sheet may have a thickness of, for example, 10 to 500 μm. The thermally conductive sheet is preferably a carbon sheet.

[0111] <<Continuous manufacturing of bonded bodies>> In the manufacturing method of this embodiment, the arrangement step and the firing step may be repeated two or more times to continuously manufacture two or more of the bonded bodies. In the manufacturing method of this embodiment, in the arrangement step, the temperature of the heating and pressing means is set to a temperature at which the bonding material can be fired before the laminate is arranged, so that the bonding material in the laminate can be fired in a short time when the firing step is subsequently performed. When the arrangement step and the firing step are repeated two or more times in this order, the effect of reducing the time is particularly remarkable.

[0112] When the positioning step and the firing step are repeated two or more times, after the first firing step is completed, the heating and pressure of the resulting bonded body are released, and the bonded body is removed from between the pair of heating and pressure means. At this stage, if the temperature of the pair of heating and pressure means is maintained at a temperature at which the bonding material can be fired (if the temperature has not been lowered to a temperature at which the bonding material cannot be fired), the pair of heating and pressure means and the elastic body are already in a state in which the positioning step can be started. Then, by positioning another laminate between the pair of heating and pressure means, the second positioning step and firing step can be immediately performed to produce the bonding material. Thereafter, by repeating this cycle, the third and subsequent bonding materials can be produced.

[0113] When the arrangement step and the firing step are repeated two or more times, the conditions of the arrangement step and the firing step may be the same for all the times, may be different for all the times, or may be the same for only some of the times. In terms of simplifying the process and maximizing the effect of time reduction, it is preferable that the conditions of the arrangement step and the firing step repeated two or more times are the same for all the times.

[0114] <<Joining material>> The bonding material used in the manufacturing method of this embodiment is not particularly limited as long as it can perform the disposing step and the firing step. A preferred bonding material includes, for example, one that contains metal particles and a solvent.

[0115] In this specification, unless otherwise specified, the term "solvent" is a concept that encompasses both a component that is liquid at room temperature and that dissolves a solute, and a component that is liquid at room temperature and that functions as a dispersion medium for dispersing a dispersoid. In this specification, "room temperature" means a temperature that is neither particularly cooled nor heated, that is, an ordinary temperature, and examples thereof include temperatures of 15 to 25°C.

[0116] The shape of the metal particles contained in the bonding material is not particularly limited, but is preferably approximately spherical. In this specification, the term "approximately spherical" refers to a shape that is spherical or can be considered as spherical, not limited to the case of the metal particles, and more specifically refers to a particle shape in which the aspect ratio calculated by [long axis of particle] / [short axis of particle] is 2 or less. The aspect ratio is preferably 1.6 or less, more preferably 1.3 or less. The surface of the approximately spherical particle may be composed of only curved surfaces, may be composed of flat surfaces, or may be composed of corners formed by connecting two flat surfaces at a predetermined angle to each other. The surface of the approximately spherical particle may be smooth or may have uneven parts.

[0117] The particle size of the metal particles at 10% cumulative volume (sometimes referred to as "D10" in this specification) measured by a laser diffraction / scattering type particle size distribution measurement is not particularly limited, but is preferably 0.18 to 0.34 μm. When D10 is equal to or greater than the lower limit, it becomes easier to adjust the viscosity of the bonding material. On the other hand, metal particles having a D10 equal to or less than the upper limit can be more easily prepared or obtained.

[0118] The particle size of the metal particles at 50% cumulative volume measured by laser diffraction / scattering particle size distribution measurement (sometimes referred to as "D50" in this specification) is not particularly limited, but is preferably more than 0.15 μm and less than 0.8 μm, and more preferably 0.2 to 0.7 μm. When D50 is in such a range, the effect of suppressing the generation of voids in the above-mentioned bonded portion is enhanced when a bonded body is produced in a shorter time than before.

[0119] The particle size of the metal particles at 90% cumulative volume measured by laser diffraction / scattering particle size distribution measurement (sometimes referred to as "D90" in this specification) is not particularly limited, but is preferably 0.45 μm or more and less than 0.8 μm, and more preferably 0.45 to 0.78 μm. When D90 is more than the lower limit or is equal to or more than the lower limit, it becomes easier to adjust the viscosity of the bonding material. On the other hand, metal particles having D90 less than the upper limit or equal to or less than the upper limit can be more easily prepared or obtained.

[0120] The metal particles contained in the bonding material may contain only one type of metal, or two or more types of metal. When there are two or more types of metal, the combination and ratio thereof can be selected arbitrarily.

[0121] The metal species of the metal particles is preferably silver or copper, and more preferably silver. That is, the metal particles are preferably silver particles or copper particles, and more preferably silver particles.

[0122] In the bonding material, the ratio of the content of the metal particles to the total mass of the bonding material ([content of metal particles in bonding material (parts by mass)] / [total mass of bonding material (parts by mass)]×100) is preferably 88.5 to 95 mass%, and may be, for example, any one of 90 to 95 mass%, 88.5 to 93 mass%, and 90 to 93 mass%. When the ratio is equal to or more than the lower limit, the bonding part can be formed more efficiently when manufacturing a bonded body in a shorter time than before, and the effect of suppressing the generation of voids in the bonding part described above is further enhanced. When the ratio is equal to or less than the upper limit, the fluidity of the bonding material is increased, and the handling property of the bonding material is improved.

[0123] The solvent contained in the bonding material is not particularly limited as long as it can be removed (vaporized) under heating conditions, and it is preferable that the solvent does not have reactivity with components other than the solvent, such as metal particles in the bonding material. Examples of the solvent include aromatic hydrocarbons such as toluene, o-xylene, m-xylene, and p-xylene; aliphatic hydrocarbons such as pentane, hexane, cyclohexane, heptane, octane, cyclooctane, nonane, decane, undecane, dodecane, tridecane, tetradecane, pentadecane, and decahydronaphthalene; halogenated hydrocarbons such as dichloromethane and chloroform; alcohols such as hexanol (e.g., 1-hexanol, etc.), heptanol (e.g., 1-heptanol, etc.), octanol (e.g., 1-octanol, etc.), nonanol (e.g., 1-nonanol, etc.), decanol (e.g., 1-decanol, etc.), benzyl alcohol, cyclohexanol, and terpineol (also known as terpineol); esters such as ethyl acetate, monomethyl glutarate, and dimethyl glutarate; and esters such as diethyl ether, tetrahydrofuran (THF), and 1,2-dimethoxyethane (dimethyl cellosolve). ethers; alcohol ethers (compounds having both a hydroxyl group and an ether bond in one molecule) such as propylene glycol monomethyl ether (also known as 1-methoxy-2-propanol), 3-methoxy-3-methyl-1-butanol, and butyl carbitol (also known as diethylene glycol monobutyl ether); ketones such as acetone, methyl ethyl ketone (MEK), and cyclohexanone; hydroxy ketones such as diacetone alcohol (also known as 4-hydroxy-4-methyl-2-pentanone); enones such as isophorone (also known as 3,5,5-trimethylcyclohex-2-en-1-one); nitriles such as acetonitrile; amides such as N,N-dimethylformamide (DMF) and N,N-dimethylacetamide; and alcohol esters (compounds having both a hydroxyl group and an ester bond in one molecule) such as texanol (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate).

[0124] The bonding material may contain only one type of solvent, or may contain two or more types of solvents. When the bonding material contains two or more types of solvents, the combination and ratio of the solvents can be selected arbitrarily.

[0125] In the bonding material, the ratio of the content of the solvent to the total mass of the bonding material ([content of the solvent in the bonding material (parts by mass)] / [total mass of the bonding material (parts by mass)]×100) is preferably 5 to 11.5% by mass, and may be, for example, any one of 5 to 10% by mass, 7 to 11.5% by mass, and 7 to 10% by mass. When the ratio is equal to or greater than the lower limit, the viscosity of the bonding material is lowered, and the handling of the bonding material is improved. When the ratio is equal to or less than the upper limit, the content of the metal particles in the bonding material can be increased, and when a bonded body is manufactured in a shorter time than before, the bonded portion can be formed more efficiently, and the effect of suppressing the generation of voids in the bonded portion described above is enhanced.

[0126] The bonding material may or may not contain other components that do not fall into the category of either metal particles or a solvent, as long as the effects of the present invention are not impaired. The other components are not particularly limited as long as they do not impair the effects of the present invention, and can be arbitrarily selected depending on the purpose.

[0127] The bonding material may contain only one type of other component, or two or more types. When there are two or more types, the combination and ratio thereof can be selected arbitrarily.

[0128] The other component contained in the bonding material may be, for example, either a resin component or a non-resin component.

[0129] In the bonding material, the ratio of the total content of the metal particles and the solvent to the total mass of the bonding material ([total content of metal particles and solvent in bonding material (parts by mass)] / [total mass of bonding material (parts by mass)]×100) is preferably 95 mass% or more, and may be, for example, 97 mass% or more or 99 mass% or more. When the ratio is equal to or more than the lower limit, the effect of suppressing the generation of voids in the bonded portion described above is increased when manufacturing a bonded body in a shorter time than before. On the other hand, the proportion is 100% by mass or less.

[0130] In the bonding material, the ratio of the content of the other components to the total mass of the bonding material ([content of the other components in the bonding material (parts by mass)] / [total mass of the bonding material (parts by mass)]×100) is preferably 5% by mass or less. When the ratio is equal to or less than the upper limit, the effect of suppressing the generation of voids in the bonding portion described above is enhanced when manufacturing a bonded body in a shorter time than before. On the other hand, the ratio is 0% by mass or more.

[0131] In the bonding material, the ratio of the total content of the one or more of the above-mentioned components to the total mass of the bonding material does not exceed 100 mass %.

[0132] The viscosity of the bonding material measured in accordance with JIS Z 3285:2017 is preferably 70 to 180 Pa·s. When the viscosity is equal to or greater than the lower limit, the effect of suppressing the generation of voids in the bonded portion described above is enhanced when a bonded body is produced in a shorter time than before. When the viscosity is equal to or less than the upper limit, the flowability of the bonding material is increased, and the handling of the bonding material is improved. The viscosity is preferably measured at a temperature of 25° C. and a rotation speed of 10 rpm (shear rate of 6 / s).

[0133] The thixotropy index of the bonding material, which is measured separately from the viscosity measurement in accordance with JIS Z 3285:2017, is preferably 0.55 to 0.95. When the viscosity of the bonding material is in the above-mentioned range and the thixotropy index is in such a range, the bonding material has more preferable characteristics. As a result, when a bonded body is manufactured in a shorter time than before, the generation of voids in the bonded portion is more suppressed.

[0134] <<Method of manufacturing bonding material>> The bonding material is obtained by blending metal particles, a solvent, and, if necessary, the other components. After the components are mixed, the obtained material may be used as the bonding material as it is, or may be used as the bonding material after a known post-treatment or purification operation is performed as necessary.

[0135] The order in which the components are mixed is not particularly limited. The method for mixing the blend is not particularly limited, and may be appropriately selected from known methods such as a method for mixing by rotating a stirrer or agitator blades, etc.; a method for mixing using a mixer, a three-roll mill, a kneader, a bead mill, etc.; a method for mixing by applying ultrasonic waves, etc.

[0136] The temperature at which each component is mixed is not particularly limited as long as the components do not deteriorate, but a temperature of 0 to 40°C is preferable. The blending time of each component is not particularly limited as long as each blended component does not deteriorate, but it is preferably 10 minutes to 12 hours. EXAMPLES

[0137] The present invention will be described in more detail below with reference to specific examples, although the present invention is not limited to the examples shown below.

[0138] [Test Example 1] <<Confirmation of the temperature history of an object when the object is heated and pressurized according to the manufacturing method of this embodiment>> A copper substrate having a size of 20 mm×20 mm and a thickness of 2 mm was prepared. A silicon carbide (SiC) chip with a size of 4.7 mm × 4.7 mm and a thickness of 0.3 mm was prepared. A titanium film (thickness 0.1 μm) was laminated on the entire surface of one side of the silicon carbide chip by plating, and a gold film (thickness 5 μm) was laminated on the entire exposed surface of the titanium film (the surface opposite to the silicon carbide chip side) by plating, thereby obtaining a silicon carbide chip with a backside coating.

[0139] A thermocouple was sandwiched between the copper substrate and the silicon carbide chip with a backside coating, and the thermocouple in this state was fixed to the copper substrate and the silicon carbide chip with a backside coating using adhesive tape to prepare a test laminate. At this time, when viewed from above in a plan view, the center of the copper substrate and the center of the silicon carbide chip with a backside coating were aligned, and the periphery of the copper substrate and the periphery of the silicon carbide chip with a backside coating were adjusted to be parallel.

[0140] A heat press machine equipped with a pair of heat press plates was prepared, which is configured so that one heat press plate is provided on the vertically lower side and the other heat press plate is provided on the vertically upper side, and the object can be clamped and heat pressed by bringing these heat press plates close together in the vertical direction. Next, a pair of hot press plates were heated to a temperature of 300°C.

[0141] Next, the test laminate was placed on the surface of the lower hot press plate on the side of the upper hot press plate (hereinafter sometimes referred to as the "upper surface") of the lower hot press plate in the hot press machine. At this time, the copper base material in the test laminate was placed in contact with the upper surface of the lower hot press plate, and the silicon carbide chips in the test laminate were placed facing the upper hot press plate without contacting the upper hot press plate. The distance between the upper surface of the lower hot press plate and the surface of the upper hot press plate on the side of the lower hot press plate (hereinafter sometimes referred to as the "lower surface") was set to 150 mm.

[0142] Next, while maintaining the temperature of the pair of hot press plates at 300°C, the upper hot press plate was quickly moved toward the lower hot press plate while keeping the position of the lower hot press plate fixed, narrowing the distance between the pair of hot press plates. Then, the lower surface of the upper hot press plate was brought into contact with the upper surface of the test laminate (in other words, the surface opposite to the lower hot press plate) and the movement of the upper hot press plate was stopped, so that the time when the pressure applied to the test laminate was maximized was set as the start time of heating and pressing the test laminate, and by maintaining this state, the test laminate was heated and pressed at a temperature of 300°C.

[0143] During this time, the temperature of the test laminate was measured by the thermocouple from the point when the test laminate was placed on the upper surface of the lower heating press plate. The results are shown in FIG.

[0144] [Test Example 2] <<Checking the temperature history of an object when it is heated and pressurized according to conventional manufacturing methods>> A test laminate was prepared in the same manner as in Test Example 1. The same heat press machine as that used in Test Example 1 was prepared. A pair of heat press plates in the heat press were heated to a temperature of 40°C.

[0145] Next, the test laminate was placed on the upper surface of the lower heat press plate in the heat press machine. The arrangement of the test laminate and the distance between the upper surface of the lower heat press plate and the lower surface of the upper heat press plate were the same as in Test Example 1.

[0146] Next, while maintaining the temperature of the pair of hot press plates at 40° C., the upper hot press plate was quickly moved toward the lower hot press plate while keeping the position of the lower hot press plate fixed, narrowing the distance between the pair of hot press plates. The lower surface of the upper hot press plate was brought into contact with the upper surface of the test laminate, and the movement of the upper hot press plate was stopped, so that the time when the pressure applied to the test laminate was maximized was determined as the start time of heating and pressing the test laminate.

[0147] Next, the pair of hot press plates was immediately heated at a temperature increase rate of 50° C. / min until the temperature reached 300° C., thereby pressing the test laminate while heating it.

[0148] During this time, the temperature of the test laminate was measured by the thermocouple from the point when the test laminate was placed on the upper surface of the lower heating press plate. The results are shown in FIG.

[0149] 5, the time from the start of heating and pressurizing the test laminate until the temperature of the test laminate reaches 300° C. is significantly shorter in Test Example 1 than in Test Example 2, more specifically, it was 49 seconds in Test Example 1 and 312 seconds in Test Example 2. These results showed that the manufacturing method of this embodiment allows a bonded body to be manufactured in a shorter time than conventional methods, even though it includes a step of heating and pressurizing the laminate.

[0150] [Example 1] << Manufacturing of bonding materials >> Metal particles (a)-1 (approximately spherical silver particles, D10=0.22 μm, D50=0.35 μm, D90=0.62 μm) (92 parts by mass) and Texanol (8 parts by mass) were weighed out into an agate mortar at room temperature and kneaded for 15 minutes. Next, the obtained kneaded material was passed through a triple roll three times to obtain the desired paste-like bonding material.

[0151] <<Evaluation of bonding materials>> The viscosity of the bonding material was measured using a micro spiral viscometer (Malcom's "PCU-02V") at a temperature of 25°C and a rotation speed of 10 rpm (shear rate of 6 / s) in accordance with JIS Z 3285:2017, and was found to be 140.0 (Pa s). Furthermore, the thixotropy index of the bonding material was measured in accordance with JIS Z 3285:2017, and was found to be 0.88.

[0152] <<Manufacturing of joints>> A copper substrate having a size of 20 mm x 20 mm and a thickness of 2 mm was prepared. The bonding material obtained above was printed on one side of the copper substrate by screen printing to form a printed layer having a size of 5 mm x 5 mm and a thickness of 0.3 mm (attachment step). At this time, when the copper substrate and the printed layer were viewed from above in a plan view, the center of the copper substrate and the center of the printed layer were aligned, and the position of the printed layer was adjusted so that the periphery of the printed layer was parallel to the periphery of the copper substrate.

[0153] In the same manner as in Test Example 1, a silicon carbide chip having a film formed on the back side was produced.

[0154] The exposed surface of the gold film in the silicon carbide chip formed on the back surface was brought into contact with the exposed surface of the printed layer formed on the copper substrate (the surface opposite to the copper substrate), thereby placing the silicon carbide chip formed on the back surface on the printed layer. In this case, when viewed from above in a plan view, the center of the printed layer was aligned with the center of the silicon carbide chip formed on the back surface, and the outer periphery of the printed layer was parallel to the outer periphery of the silicon carbide chip formed on the back surface (overlapping step (i)).

[0155] Next, the printed layer was heated at 110°C for 10 minutes in air, without pressure (normal pressure), and with a wind speed of 1.5 m / s using a forced convection oven (Espec Corp.'s "PH-202") (pre-drying process (i)). As a result of the above, a laminate was obtained in which the copper base material, the heated printed layer (dried bonding material), and the silicon carbide chip with a film formed on its back surface were laminated in this order in the thickness direction.

[0156] A spring made of SUS304WPB (Samini's "F7701", hereafter sometimes referred to as the "SUS spring") made of SUS304 was prepared. This SUS spring was a coil with a truncated cone shape similar to that shown in FIG. 4, with a wire diameter (diameter of the SUS wire) of 0.5 mm, a free length (H1) of 8 mm, a small outer diameter (D2) of 4 mm, and a large outer diameter (D1) of 9 mm. When this SUS spring was maximally contracted until its length in the central axis direction (the direction in which it can expand and contract) was at its minimum, the SUS wires constituting this spring did not overlap each other in the central axis direction of the spring at all regions, and the thickness of the SUS spring was equivalent to the diameter of the SUS wire. The thermal conductivity of the SUS spring was 16.7 W / (m·K) and the spring constant was 0.42 N / mm.

[0157] The same heat press machine as that used in Test Example 1 was prepared. Three of the above-mentioned SUS springs were placed on the upper surface of the lower heat press plate in the heat press machine. At this time, the three SUS springs were placed with their large outer diameter ends in contact with the upper surface of the lower heat press plate. Furthermore, the three SUS springs were placed on the upper surface so that they formed the vertices of an equilateral triangle.

[0158] Next, a pair of hot press plates were heated to a temperature of 300°C. Next, the laminate was placed on the small outer diameter end of the three SUS springs on the lower hot press plate without contacting the upper hot press plate. At this time, the copper base material in the laminate was in contact with the SUS spring, and the silicon carbide chips in the laminate were placed facing the upper hot press plate without contacting the upper hot press plate. Furthermore, a carbon sheet (thickness 50 μm) was placed on the entire exposed surface of the upper hot press plate side of the laminate (in other words, the surface of the silicon carbide chips in the laminate opposite to the heated printing layer side). In this way, the length of the SUS spring in the central axis direction with the laminate and the carbon sheet placed was 7.5 mm. The distance L1 between the heated printing layer (dried bonding material) and the lower hot press plate (the distance between the surface of the heated printing layer on the copper base material side and the upper surface of the lower hot press plate) was 9.5 mm. On the other hand, the distance L2 between the heated printing layer (dried bonding material) and the upper heating press plate (the distance between the surface of the heated printing layer on the silicon carbide chip side and the lower surface of the upper heating press plate) was 210 mm. Thus, the laminate was placed between the pair of hot press plates (placement step).

[0159] Next, while maintaining the temperature of the pair of hot press plates at 300°C, the upper hot press plate was quickly moved toward the lower hot press plate while keeping the position of the lower hot press plate fixed, narrowing the distance between the pair of hot press plates. By narrowing the distance in this manner, the lower surface of the upper hot press plate was brought into contact with the upper surface of the laminate (in other words, the surface opposite the SUS spring side) via the carbon sheet. The time from placing the laminate between the pair of hot press plates until the upper hot press plate came into contact with the carbon sheet (laminate) was 20 seconds or less.

[0160] In this way, the time when the upper hot press plate contacted the laminate was the start time of heating and pressing the laminate. Then, the upper hot press plate was moved further toward the lower hot press plate, and finally, all three SUS springs were maximally contracted until their lengths in the central axis direction (the direction in which they can expand and contract) became minimum so that the thickness of the three SUS springs was equivalent to the diameter of the SUS wire, and at this point, the movement of the upper hot press plate was stopped. In this way, after the upper hot press plate was brought into contact with the laminate (from the start time of heating and pressing the laminate), the SUS springs were maximally contracted and the movement of the upper hot press plate was stopped, so that the pressure applied to the laminate became 15 MPa, and it took 32 seconds for it to reach its maximum.

[0161] Next, by maintaining this state, the laminate was heated at a temperature of 300°C while being pressurized at a pressure of 15 MPa, and the laminate was heated and pressurized in this manner for 49 seconds. According to the results of Test Example 1, it was estimated that the temperature of the laminate had reached approximately 300°C at this point. The laminate was further heated and pressurized in this manner for 300 seconds. In this manner, the laminate was heated and pressurized for 349 seconds, whereby the heated printed layer (dried bonding material) was fired to form a bond (firing process).

[0162] Next, the pair of hot press plates was immediately cooled with water to lower its temperature to room temperature, and then the pressure applied to the laminate by the pair of hot press plates was released. As a result of the above, a bonded body was obtained in which a copper base material and a silicon carbide chip having a film formed on its back surface were bonded together via a conductive bonding part made of a silver sintered body. In the resulting bonded body, the size of the bonded portion was 4.7 mm×4.7 mm, and the thickness was 0.1 mm.

[0163] <<Evaluation of bonding materials>> <Measurement of porosity of joint> The bonded body obtained above was sealed with epoxy resin. The bonded body after sealing was cut so that the center of the silicon carbide chip in the bonded body in this state was cut in a direction perpendicular to the surface of the silicon carbide chip, thereby preparing a cross section of the bonded body. The prepared cross section was further subjected to mechanical polishing and ion milling. Next, the cross section of the bonded part among the cross sections was observed using an SEM under the condition of an acceleration voltage of 5 kV (reflected electron image), and the black area in the image data obtained by performing binarization processing was classified as a void part. Then, the ratio of the area of ​​the void part to the area of ​​the cross section of the bonded part was calculated, and the value was adopted as the porosity of the bonded part. As a result, the porosity of the bonded part was 5.2%.

[0164] As is clear from the above results, in this embodiment, even though it includes a process of heating and pressurizing the laminate, it is possible to manufacture a bonded body (fire the bonding material) in a shorter time than conventional methods, and moreover, it is possible to form a dense bond in which the occurrence of voids is suppressed.

[0165] [Comparative Example 1] << Manufacturing of bonding materials >> A bonding material was obtained in the same manner as in Example 1.

[0166] <<Manufacturing of joints>> A laminate was prepared in the same manner as in Example 1. The same heat press machine as that used in Test Example 1 was prepared. A pair of heat press plates was heated to a temperature of 40°C. Next, the laminate was placed on the upper surface of the lower hot press plate without contacting the upper hot press plate.

[0167] Next, while maintaining the temperature of the pair of hot press plates at 40° C., the upper hot press plate was quickly moved toward the lower hot press plate while keeping the position of the lower hot press plate fixed, narrowing the distance between the pair of hot press plates. Then, the lower surface of the upper hot press plate was brought into contact with the upper surface of the laminate (in other words, the surface opposite to the lower hot press plate) and the movement of the upper hot press plate was stopped, thereby pressing the laminate with a pressure of 15 MPa. Next, the pair of hot press plates were immediately heated for 312 seconds at a temperature rise rate of 50°C / min. According to the results of Test Example 2, it was estimated that the temperature of the laminate reached approximately 300°C at this point. Furthermore, the heating and pressurizing of the laminate was continued in this manner for 600 seconds. In this manner, by heating and pressurizing the laminate for 600 seconds, the heated printing layer (dried bonding material) was fired to form a bond (firing process). In this comparative example, the heating and pressurizing time of the laminate after the temperature of the laminate reached approximately 300°C was set to the same as in Example 1.

[0168] Next, the pair of hot press plates was immediately cooled with water to lower its temperature to room temperature, and then the pressure applied to the laminate by the pair of hot press plates was released. As a result of the above, a comparative joint was obtained in which a copper base material and a silicon carbide chip with a film formed on its back surface were joined via a conductive joint made of a silver sintered body. In the obtained comparative joint, the size of the joint was 4.7 mm×4.7 mm and the thickness was 0.1 mm.

[0169] <<Evaluation of bonding materials>> For the obtained comparative joint, the porosity of the joint was measured by the same method as in Example 1, and was found to be 2.5%.

[0170] As is clear from the above results, in Example 1, the same level of porosity in the joints as in Comparative Example 1 could be achieved even though the time for heating and pressurizing the laminate was about half. [Industrial Applicability]

[0171] The present invention can be used in the manufacture of conductive junctions, particularly semiconductor devices. [Explanation of symbols]

[0172] 1...zygote, 11: conductive first part; 11a: one surface of the conductive first part 12: conductive second part; 12a: one surface of the conductive second part 13... conductive joint, 130... joint material (dried joint material, liquid joint material) 101...Laminate 8: Thermally conductive elastomer; 8b: Other part of the thermally conductive elastomer on the heating and pressurizing means side (the end of the thermally conductive elastomer on the small outer diameter side) 9: a pair of heating and pressing means; 91: one heating and pressing means; 92: the other heating and pressing means; 91a: a surface of one heating and pressing means on the other heating and pressing means side

Claims

1. A method for producing a bonded body, comprising the steps of: the joined body is configured by joining a conductive first part and a conductive second part via a conductive joint, The manufacturing method includes a step of placing a laminate formed by stacking the conductive first component, the bonding material, and the conductive second component in this order in a thickness direction between a pair of heating and pressing means; A firing process in which the bonding material is fired by heating and pressurizing the laminate by the heating and pressurizing means to form the bonding portion from the bonding material, In the arranging step, the temperature of the pair of heating and pressing means is adjusted to a temperature at which the bonding material can be fired, a thermally conductive elastic body that is expandable and contractible in a direction connecting the pair of heating and pressing means is arranged on a surface of one of the heating and pressing means facing the other heating and pressing means, and the laminate is placed on a portion of the elastic body facing the other heating and pressing means without contacting the other heating and pressing means, thereby arranging the laminate between the pair of heating and pressing means, In the firing process, the temperature of the pair of heating and pressing means is maintained at a temperature at which the bonding material can be fired, while the distance between the pair of heating and pressing means is narrowed, thereby bringing the other heating and pressing means into contact with the laminate, and heating and pressing the laminate.

2. The method for producing a joint body according to claim 1 , wherein the elastic body is a coil having a conical, pyramidal, truncated conical or truncated pyramidal shape.

3. 3. The method for manufacturing a bonded body according to claim 1, wherein one or both of a temperature at which the bonding material can be fired in the placing step and a temperature at which the bonding material can be fired in the firing step are 180°C or higher.

4. The method for producing a bonded body according to claim 1 , wherein the disposing step and the firing step are repeated two or more times to continuously produce two or more of the bonded bodies.

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