Bonding material, semiconductor device, and method for producing bonding material

Abstract

This bonding material comprises a base material and a first bonding layer. The base material has a first surface which faces one side in a first direction. The first bonding layer is laminated on the first surface. The base material contains a metal. The first bonding layer contains a metal and an organic compound. The entirety of the first bonding layer is positioned further to the opposite side than the base material in the first direction, relative to the first surface. The base material has a first layer and a second layer that is positioned between the first layer and the first bonding layer. The first layer and the second layer respectively include differing metals.

Description

Bonding material, semiconductor device, and method for manufacturing bonding material

[0001] The present disclosure relates to a bonding material, a method for manufacturing the same, and a semiconductor device including the bonding material.

[0002] Patent Document 1 discloses an example of a semiconductor device including a heat radiating fin. The semiconductor device includes a heat radiating fin, a heat radiator disposed on the heat radiating fin, a heat sink disposed on the heat radiator, a semiconductor element disposed on the heat sink, and a sealing body covering the semiconductor element. The heat radiator is sandwiched between the heat radiating fin and the heat sink. Heat generated from the semiconductor element is conducted from the heat sink to the heat radiating fin via the heat radiator. The sealing body is fixed to the heat radiating fin via a screw.

[0003] Here, unlike the semiconductor device disclosed in Patent Document 1, there are cases where in addition to the function of efficiently conducting heat, a function of bonding the heat radiating fin and the heat sink is imparted to the heat radiator. This eliminates the need for a screw for fixing the sealing body to the heat radiating fin. In this case, a sintering material containing metal particles may be used as the heat radiator. However, the sintering material has a problem that it is relatively expensive.

[0004] International Publication No. 2019 / 239997

[0005] [Summary] An object of the present disclosure is to provide an improved bonding material compared to conventional ones. In particular, in view of the above circumstances, an object of the present disclosure is to provide a bonding material that can reduce manufacturing costs without causing a decrease in heat dissipation.

[0006] The bonding material provided by the first aspect of the present disclosure includes a base material having a first surface facing one side in a first direction, and a first bonding layer laminated on the first surface. The base material contains a metal. The first bonding layer contains a metal and an organic compound. The entire first bonding layer is located on the opposite side of the base material with reference to the first surface in the first direction.

[0007] A semiconductor device provided by a second aspect of this disclosure comprises a bonding material provided by a first aspect of this disclosure, a substrate, a semiconductor element mounted on the substrate on one side of the substrate in the first direction, a sealing resin covering the semiconductor element, and a heat dissipation member. The heat dissipation member is located on the opposite side from the semiconductor element with respect to the substrate. The substrate is exposed from the sealing resin. The bonding material further comprises a second bonding layer. The bonding material bonds the heat dissipation member and the substrate.

[0008] A method for manufacturing a bonding material provided by a third aspect of this disclosure comprises the step of placing a first bonding layer containing a metal and an organic compound on one side in a first direction of a base material containing a metal. In the step of placing the first bonding layer, the material of the first bonding layer, which contains an organic solvent and is in paste form, is applied to the base material, and the material is dried so that the organic solvent remains.

[0009] A method for manufacturing a bonding material provided by a fourth aspect of this disclosure comprises the step of placing a first bonding layer containing a metal and an organic compound on one side in a first direction of a base material containing a metal. In the step of placing the first bonding layer, the first bonding layer, which is in a solid-liquid mixture state and maintains its shape, is pressed onto the base material.

[0010] Other features and advantages of this disclosure will become more apparent from the detailed description below, based on the accompanying drawings.

[0011] Figure 1 is a cross-sectional view of a bonding material according to the first embodiment of the present disclosure. Figure 2 is a partially enlarged view of Figure 1. Figure 1 is a cross-sectional view illustrating the first step in the manufacturing method of the bonding material shown in Figure 1. Figure 1 is a cross-sectional view illustrating the second step in the manufacturing method of the bonding material shown in Figure 1. Figure 1 is a cross-sectional view illustrating the third step in the manufacturing method of the bonding material shown in Figure 1. Figure 1 is a cross-sectional view illustrating the first step in the manufacturing method of the bonding material shown in Figure 1. Figure 1 is a cross-sectional view illustrating the second step in the manufacturing method of the bonding material shown in Figure 1. Figure 8 is a plan view of a semiconductor device comprising the bonding material shown in Figure 1. Figure 9 is a plan view corresponding to Figure 8, and is transparent to the sealing resin and heat dissipation member. Figure 10 is a cross-sectional view along the line X-X in Figure 9. Figure 11 is a partially enlarged cross-sectional view of a bonding material according to the second embodiment of the present disclosure. Figure 12 is a partially enlarged cross-sectional view of a bonding material according to the third embodiment of the present disclosure. Figure 13 is a partially enlarged cross-sectional view of a bonding material according to the fourth embodiment of the present disclosure. Figure 14 is a partially enlarged cross-sectional view of a bonding material according to the fifth embodiment of the present disclosure.

[0012] [Detailed Explanation] Details of this disclosure will be explained with reference to the attached drawings.

[0013] First Embodiment: A bonding material A10 according to the first embodiment of the present disclosure will be described with reference to Figures 1 and 2. 10 comprises a base material 11, a first bonding layer 12, a second bonding layer 13, and two protective layers 19.

[0014] In the description of the bonding material A10 and the semiconductor device B described later, for convenience, the direction normal to the first surface 11A of the base material 11 described later will be called the "first direction z". The direction perpendicular to the first direction z will be called the "second direction x". The direction perpendicular to both the first direction z and the second direction x will be called the "third direction y".

[0015] As shown in Figures 1 and 2, the base material 11 has a first surface 11A and a second surface 11B that face opposite each other in a first direction z. The base material 11 contains metal and is in sheet form. The first bonding layer 12 is laminated on the first surface 11A. The entire first bonding layer 12 is located on the opposite side of the base material 11 with respect to the first surface 11A in the first direction z. The second bonding layer 13 is laminated on the second surface 11B. The entire second bonding layer 13 is located on the opposite side of the base material 11 with respect to the second surface 11B in the first direction z. Therefore, the entirety of each of the first bonding layer 12 and the second bonding layer 13 is located outward from the entirety of the base material 11 sandwiched between the first surface 11A and the second surface 11B. Each of the first bonding layer 12 and the second bonding layer 13 contains a metal and an organic compound. The organic compound contains a binder such as a resin and an organic solvent. The first bonding layer 12 and the second bonding layer 13 both contain silver (Ag). Therefore, the first bonding layer 12 and the second bonding layer 13 contain the same metal. Since each of the first bonding layer 12 and the second bonding layer 13 contains a metal and an organic solvent, they are in a solid-liquid mixed state. In bonding material A10, the first bonding layer 12 and the second bonding layer 13 are made of the same material.

[0016] As shown in Figure 2, the dimension t2 of the first bonding layer 12 in the first direction z is smaller than the dimension t1 of the base material 11 in the first direction z. The dimension t3 of the second bonding layer 13 in the first direction z is smaller than the dimension t1 of the base material 11 in the first direction z.

[0017] As shown in Figure 2, the bonding layer 80 has a first layer 111, a second layer 112, a third layer 113, a fifth layer 115, and a sixth layer 116. The second layer 112 is located between the base material 11 and the first bonding layer 12. The second layer 112 is laminated on the base material 11. The fifth layer 115 is located between the base material 11 and the second bonding layer 13. The fifth layer 115 is laminated on the base material 11. The third layer 113 is located on the opposite side of the base material 11 with respect to the second layer 112 in the first direction z. The third layer 113 includes a first surface 11A. The first bonding layer 12 is in contact with the first surface 11A. The sixth layer 116 is located on the opposite side of the base material 11 with respect to the fifth layer 115 in the first direction z. The sixth layer 116 includes a second surface 11B. The second bonding layer 13 is in contact with the second surface 11B. The dimensions in the first direction z of each of the second layer 112, third layer 113, fifth layer 115, and sixth layer 116 are smaller than the dimensions in the first direction z of the first layer 111.

[0018] The metals contained in each of the second layer 112, third layer 113, fifth layer 115, and sixth layer 116 are different from the metals contained in the first layer 111. The second layer 112 and fifth layer 115 contain the same metal as each other. The third layer 113 and sixth layer 116 contain the same metal as each other. The first layer 111 contains aluminum (Al). In addition, the first layer 111 may also contain copper (Cu). The second layer 112 and fifth layer 115 each contain either titanium (Ti) or nickel (Ni). The third layer 113 and sixth layer 116 both contain silver. Therefore, the Young's modulus of the metal contained in the first layer 111 is lower than the Young's modulus of the metal contained in each of the third layer 113 and sixth layer 116.

[0019] As shown in Figure 1, the two protective layers 19 individually cover the first bonding layer 12 and the second bonding layer 13. The two protective layers 19 are films that have excellent sealing properties and are peelable. By having the two protective layers 19 in the bonding material A10, drying and deterioration of the first bonding layer 12 and the second bonding layer can be prevented.

[0020] Next, a first embodiment of the method for manufacturing the bonding material A10 will be described based on Figures 3 to 5. Each cross-sectional position in Figures 3 to 5 corresponds to the cross-sectional position in Figure 1.

[0021] First, the first step P1 shown in Figure 3 is performed. In the first step P1, the base material 11 is formed in advance, and then the first bonding layer 12 is placed on one side of the base material 11 in the first direction z. When forming the base material 11, the second layer 112 and fifth layer 115, the third layer 113 and sixth layer 116 are laminated in that order to the first layer 111. If the second layer 112 and fifth layer 115 contain nickel, the surface of the first layer 111 is treated with zincate, and then the second layer 112 and fifth layer 115 are formed by electroless plating. If the second layer 112 and fifth layer 115 contain titanium, the second layer 112 and fifth layer 115 are formed by sputtering onto the first layer 111. The third layer 113 and sixth layer 116 are formed by electrolytic plating or electroless plating.

[0022] After forming the base material 11 in advance, the first bonding layer 12 is placed on one side of the base material 11 in the first direction z. When placing the first bonding layer 12, the material of the first bonding layer 12, which contains an organic solvent and is in paste form, is applied to the base material 11. After that, the material of the first bonding layer 12 is dried so that the organic solvent remains.

[0023] Next, the second step P2 shown in Figure 4 is performed. In the second step P2, the second bonding layer 13 is placed on the side opposite to the side where the first bonding layer 12 is located, with respect to the base material 11 in the first direction z. The method for placing the second bonding layer 13 is the same as the method for placing the first bonding layer 12 in the first step P1.

[0024] Finally, the third step P3 shown in Figure 5 is performed. In the third step P3, the two protective layers 19 are individually attached to the first bonding layer 12 and the second bonding layer 13. By going through the above steps, the bonding material A10 is obtained.

[0025] Next, a second embodiment of the method for manufacturing the bonding material A10 will be described based on Figures 6 and 7. The respective cross-sectional positions in Figures 6 and 7 correspond to the cross-sectional positions in Figure 1.

[0026] In the second embodiment, the first step P1 and the second step P2 differ from those of the first embodiment described above. In the first step P1 shown in Figure 6, the first bonding layer 12, which is in a solid-liquid mixed state and maintains its shape, is pressed onto one side of the base material 11 in the first direction z. In the second step P2 shown in Figure 7, the second bonding layer 13 is placed on the side opposite to the side where the first bonding layer 12 is located, with the base material 11 as the reference in the first direction z. The method for placing the second bonding layer 13 is the same as the method for placing the first bonding layer 12 in the first step P1.

[0027] Next, a semiconductor device B equipped with a bonding material A10 will be described, as shown in Figures 8 to 10. In addition to the bonding material A10, the semiconductor device B includes a substrate 21, a first power terminal 22, two second power terminals 23, two third power terminals 24, a plurality of first semiconductor elements 31, a plurality of second semiconductor elements 32, a first conductive member 41, a second conductive member 42, a sealing resin 50, and a heat dissipation member 70. Here, in Figure 9, for the sake of understanding, the sealing resin 50 and the heat dissipation member 70 are shown as transparent. In Figure 9, the transparent sealing resin 50 and the heat dissipation member 70 are each shown by dashed lines (double-dotted lines).

[0028] Semiconductor device B converts the DC power input to the first power terminal 22 and the two third power terminals 24 into AC power using a plurality of first semiconductor elements 31 and a plurality of second semiconductor elements 32. The converted AC power is input to a power supply target such as a motor through each of the two second power terminals 23.

[0029] As shown in Figure 10, the substrate 21 is located on one side of the first direction z for each of the multiple first semiconductor elements 31 and the multiple second semiconductor elements 32 in the first direction z. In the semiconductor device B, the substrate 21 is made from a substrate formed by, for example, an active metal blazing (AMB) method. As shown in Figure 10, the substrate 21 includes an insulating layer 211, a first conductive layer 212, a second conductive layer 213, and a heat dissipation layer 214. The substrate 21 is covered with a sealing resin 50, except for a portion of the heat dissipation layer 214.

[0030] As shown in Figure 8, the insulating layer 211 includes a portion interposed between the heat dissipation layer 214 and the first conductive layer 212 and the second conductive layer 213 in the first direction z. The insulating layer 211 is made of a material with relatively high thermal conductivity. The insulating layer 211 is made of, for example, aluminum nitride (AlN) or silicon nitride (Si ３ N ４ It consists of ceramics containing ).

[0031] As shown in Figure 10, the first conductive layer 212 and the second conductive layer 213 are located between the insulating layer 211 and the plurality of first semiconductor elements 31 and the plurality of second semiconductor elements 32 in the first direction z. The first conductive layer 212 and the second conductive layer 213 are bonded to the insulating layer 211. Both the first conductive layer 212 and the second conductive layer 213 contain copper. The first conductive layer 212 and the second conductive layer 213 are separated from each other in the second direction x.

[0032] As shown in Figure 10, the heat dissipation layer 214 is located in the first direction z, relative to the insulating layer 211, on the opposite side from the first conductive layer 212 and the second conductive layer 213. The heat dissipation layer 214 is exposed from the sealing resin 50. The heat dissipation layer 214 contains metal. The heat dissipation layer 214 contains copper.

[0033] As shown in Figures 9 and 10, the multiple first semiconductor elements 31 are mounted on the first conductive layer 212. The multiple first semiconductor elements 31 are conductively bonded to the first conductive layer 212. The multiple first semiconductor elements 31 are arranged along the third direction y. As shown in Figures 9 and 10, the multiple second semiconductor elements 32 are mounted on the second conductive layer 213. The multiple second semiconductor elements 32 are conductively bonded to the second conductive layer 213. The multiple second semiconductor elements 32 are arranged along the third direction y. The multiple first semiconductor elements 31 and the multiple second semiconductor elements 32 are, for example, MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors). In addition, the multiple first semiconductor elements 31 and the multiple second semiconductor elements 32 may be switching elements such as IGBTs (Insulated Gate Bipolar Transistors). Furthermore, the plurality of first semiconductor elements 31 may include a plurality of switching elements and a plurality of freewheeling diodes individually connected in parallel to these switching elements. Similarly, the plurality of second semiconductor elements 32 may also include a plurality of switching elements and a plurality of freewheeling diodes individually connected in parallel to these switching elements. The freewheeling diodes are, for example, Schottky barrier diodes. In the description of semiconductor device B, the plurality of first semiconductor elements 31 and the plurality of second semiconductor elements 32 are n-channel type and vertical structure MOSFETs. The plurality of first semiconductor elements 31 and the plurality of second semiconductor elements 32 include a compound semiconductor substrate. The compound semiconductor substrate includes silicon carbide (SiC).

[0034] As shown in Figure 9, the first power terminal 22 is located in the second direction x, with reference to the plurality of first semiconductor elements 31, on the opposite side from the plurality of second semiconductor elements 32. The first power terminal 22 is conductively bonded to the first conductive layer 212. As a result, the first power terminal 22 is electrically connected to the plurality of first semiconductor elements 31 via the first conductive layer 212. The first power terminal 22 is the P terminal (positive electrode) to which the DC power to be converted is input. A portion of the first power terminal 22 protrudes from the sealing resin 50.

[0035] As shown in Figure 9, each of the two second power terminals 23 is located on the opposite side of the first conductive layer 212 from the second conductive layer 213 in the second direction x. Each of the two second power terminals 23 is conductively bonded to the second conductive layer 213. As a result, each of the two second power terminals 23 is electrically connected to the plurality of second semiconductor elements 32 via the second conductive layer 213. AC power converted by the plurality of first semiconductor elements 31 and the plurality of second semiconductor elements 32 is output from each of the two second power terminals 23. Parts of the two second power terminals 23 protrude from the sealing resin 50.

[0036] As shown in Figure 9, the two third power terminals 24 are located on the opposite side of the multiple second semiconductor elements 32 in the second direction x, with reference to the multiple first semiconductor elements 31. The two third power terminals 24 are located on both sides of the first power terminal 22 in the third direction y. Each of the two third power terminals 24 is conductive to the multiple second semiconductor elements 32. The two third power terminals 24 are N terminals (negative electrodes) to which the DC power to be converted is input. Parts of the two second power terminals 23 protrude from the sealing resin 50.

[0037] As shown in Figure 10, the first conductive member 41 is electrically bonded to the plurality of first semiconductor elements 31 and the third layer 113. As a result, the plurality of second semiconductor elements 32 are electrically connected to the plurality of first semiconductor elements 31.

[0038] As shown in Figures 9 and 10, the second conductive member 42 is electrically connected to a plurality of second semiconductor elements 32 and two third power terminals 24. As a result, each of the two third power terminals 24 is electrically connected to the plurality of second semiconductor elements 32.

[0039] As shown in Figure 10, the sealing resin 50 covers the insulating layer 211, the first conductive layer 212, the second conductive layer 213, the plurality of first semiconductor elements 31, the plurality of second semiconductor elements 32, the first conductive member 41, and the second conductive member 42. The sealing resin 50 is exposed to the outside and faces the heat dissipation member 70. The sealing resin 50 has electrical insulating properties. The sealing resin 50 is made of a material including, for example, a black epoxy resin.

[0040] As shown in FIG. 10, the heat dissipation member 70 is located on the opposite side of the plurality of first semiconductor elements 31 and the plurality of second semiconductor elements 32 with respect to the base material 21 in the first direction z. The heat dissipation member 70 is exposed to the outside similarly to the sealing resin 50. The heat dissipation member 70 contains metal. The heat dissipation member 70 has a base portion 71 and a heat dissipation portion 72.

[0041] As shown in FIG. 10, the base portion 71 supports the base material 21. The base portion 71 has a flat plate shape. The heat dissipation portion 72 is located on the opposite side of the base portion 71 from the base material 21 in the first direction z. The heat dissipation portion 72 protrudes from the base portion 71 in the first direction z. The heat dissipation portion 72 is composed of, for example, a plurality of fins. In addition, the shape and the like of the heat dissipation portion 72 can be freely set. Each of the base portion 71 and the heat dissipation portion 72 is made of, for example, a material containing aluminum (Al).

[0042] As shown in FIG. 10, the bonding material A10 bonds the base portion 71 of the heat dissipation member 70 to the heat dissipation layer 214 of the base material 21. For bonding, the bonding material A10 from which the two protective layers 19 have been removed is arranged between the base portion 71 and the heat dissipation layer 214. Thereafter, the heat dissipation layer 214 is bonded to the base portion 71 via the bonding material A10 by heating and pressing. The first bonding layer 12 of the bonding material A10 is in contact with the heat dissipation layer 214. The second bonding layer 13 of the bonding material A10 is in contact with the base portion 71.

[0043] Next, the functions and effects of the bonding material A10 will be described.

[0044] The bonding material A10 includes a base material 11 and a first bonding layer 12 laminated on a first surface 11A of the base material 11. The base material 11 contains a metal. The first bonding layer 12 contains a metal and an organic compound. The entire first bonding layer 12 is located on the opposite side of the base material 11 with reference to the first surface 11A in the first direction z. By adopting this configuration, using the base material 11, which has a lower material cost than the first bonding layer 12, together with the first bonding layer 12 reduces the ratio of the volume of the first bonding layer 12 to the total volume of the bonding material A10. Thereby, the material cost of the bonding material A10 can be reduced. Furthermore, since each of the base material 11 and the first bonding layer 12 contains a metal, the thermal conductivity of the bonding material A10 becomes relatively high. Therefore, according to this configuration, it is possible to reduce the manufacturing cost of the bonding material A10 without causing a decrease in the heat dissipation performance of the bonding material A10.

[0045] The base material 11 has a first layer 111 and a second layer 112. The first bonding layer 12 is laminated on the second layer 112. The first layer 111 and the second layer 112 contain different metals from each other. For example, when the first bonding layer containing silver is laminated on the base material 11 containing only aluminum, there is a risk that the first bonding layer 12 peels off from the base material 11. Therefore, after providing the first layer 111 containing aluminum, by interposing the second layer 112 containing a metal other than aluminum between the first layer 111 and the first bonding layer 12, peeling of the first bonding layer 12 can be prevented.

[0046] The Young's modulus of the metal contained in the first layer 111 of the base material 11 is lower than the Young's modulus of the metal contained in the first bonding layer 12. By adopting this configuration, in the semiconductor device B, the reaction force acting from the bonding material A10 to the heat dissipation layer 214 of the base material 21 is reduced. Thereby, the bending stress acting on the base material 21 is reduced.

[0047] The base material 11 has a third layer 113. The third layer 113 includes the first surface 11A. The metal contained in the third layer 113 is the same as the metal contained in the first bonding layer 12. By adopting this configuration, in the semiconductor device B, the interface between the first surface 11A and the first bonding layer 12 becomes stronger.

[0048] The bonding material A10 contains a metal and an organic compound and further comprises a second bonding layer 13 laminated on the second surface 11B of the base material 11. The entire second bonding layer 13 is located on the opposite side of the base material 11 with respect to the second surface 11B in the first direction z. With this configuration, in the semiconductor device B, the first bonding layer 12 contributes to bonding the heat dissipation layer 214 of the substrate 21, and the second bonding layer 13 contributes to bonding the base portion 71 of the heat dissipation member 70. As a result, the degree of heating and pressurization can be reduced when bonding the substrate 21 to the heat dissipation member 70.

[0049] Second Embodiment: A joint member A20 according to the second embodiment of the present disclosure will be described based on Figure 11. In this figure, elements that are the same as or similar to those of the joint member A10 described above are denoted by the same reference numerals, and redundant explanations are omitted. Here, the cross-sectional position in Figure 11 corresponds to Figure 2, which shows the joint member A10.

[0050] In the bonding material A20, the configuration of the second bonding layer 13 and the two protective layers 19 differs from that of the bonding material A10.

[0051] As shown in Figure 11, the bonding material A20 does not have a second bonding layer 13. Furthermore, the bonding material A20 has a protective layer 19 instead of two protective layers 19. The protective layer 19 covers only the first bonding layer 12. The second surface 11B of the base material 11 is exposed to the outside.

[0052] In semiconductor device B (see Figure 10), when bonding material A20 is applied instead of bonding material A10, the second surface 11B is in contact with the base 71 of the heat dissipation member 70. In this case, a bonding interface is formed between the second surface 11B and the base 71 by solid-phase diffusion.

[0053] Next, the effects of the bonding material A20 will be explained.

[0054] The bonding material A20 comprises a base material 11 and a first bonding layer 12 laminated on the first surface 11A of the base material 11. The base material 11 contains a metal. The first bonding layer 12 contains a metal and an organic compound. The entire first bonding layer 12 is located on the opposite side of the base material 11 in the first direction z, with reference to the first surface 11A. Therefore, this configuration makes it possible to reduce the manufacturing cost of the bonding material A20 without causing a decrease in the heat dissipation performance of the bonding material A20. Furthermore, by having a configuration common to bonding material A10, bonding material A20 achieves the same effects as bonding material A10.

[0055] Third Embodiment: A joint member A30 according to the third embodiment of the present disclosure will be described based on Figure 12. In this figure, elements that are the same as or similar to those of the joint member A10 described above are denoted by the same reference numerals, and redundant explanations are omitted. Here, the cross-sectional position in Figure 12 corresponds to Figure 2, which shows the joint member A10.

[0056] In the joining material A30, the structure of the base material 11 differs from that of the joining material A10.

[0057] As shown in Figure 12, the base material 11 has a fourth layer 114 and a seventh layer 117. The fourth layer 114 is located between the second layer 112 and the third layer 113 of the base material 11. The seventh layer 117 is located between the fifth layer 115 and the sixth layer 116 of the base material 11. The fourth layer 114 and the seventh layer 117 contain the same metal. Both the fourth layer 114 and the seventh layer 117 contain copper. The dimension of the fourth layer 114 and the seventh layer 117 in the first direction z is smaller than the dimension of the first layer 111 of the base material 11 in the first direction z.

[0058] Next, we will explain the effects and benefits of the bonding material A30.

[0059] The bonding material A30 comprises a base material 11 and a first bonding layer 12 laminated on the first surface 11A of the base material 11. The base material 11 contains a metal. The first bonding layer 12 contains a metal and an organic compound. The entire first bonding layer 12 is located on the opposite side of the base material 11 in the first direction z, with respect to the first surface 11A. Therefore, this configuration makes it possible to reduce the manufacturing cost of the bonding material A30 without causing a decrease in the heat dissipation performance of the bonding material A30. Furthermore, by having a configuration common to bonding material A10, bonding material A30 achieves the same effects as bonding material A10.

[0060] Fourth Embodiment: A joint member A40 according to the fourth embodiment of the present disclosure will be described based on Figure 13. In this figure, elements that are the same as or similar to those of the joint member A10 described above are denoted by the same reference numerals, and redundant explanations are omitted. Here, the cross-sectional position in Figure 13 corresponds to Figure 2, which shows the joint member A10.

[0061] In joining material A40, the structure of the base material 11 differs from that of joining material A10.

[0062] As shown in Figure 13, the basic structure of the base material 11 is similar to that of the base material 11 of the joining material A10. However, the metals contained in the third layer 113 and the sixth layer 116 of the base material 11 are different from those in the joining material A10. Both the third layer 113 and the sixth layer 116 contain copper.

[0063] Next, we will explain the effects and benefits of the bonding material A40.

[0064] The bonding material A40 comprises a base material 11 and a first bonding layer 12 laminated on the first surface 11A of the base material 11. The base material 11 contains a metal. The first bonding layer 12 contains a metal and an organic compound. The entire first bonding layer 12 is located on the opposite side of the base material 11 in the first direction z, with respect to the first surface 11A. Therefore, this configuration makes it possible to reduce the manufacturing cost of the bonding material A40 without causing a decrease in the heat dissipation performance of the bonding material A40. Furthermore, by having a configuration common to bonding material A10, bonding material A40 achieves the same effects and performance as bonding material A10.

[0065] Fifth Embodiment: A joint member A50 according to the fifth embodiment of the present disclosure will be described with reference to Figure 14. In this figure, elements that are the same as or similar to those of the joint member A10 described above are denoted by the same reference numerals, and redundant explanations are omitted. Here, the cross-sectional position in Figure 14 corresponds to Figure 2, which shows the joint member A10.

[0066] In the joining material A50, the structure of the base material 11 differs from that of the joining material A10.

[0067] As shown in Figure 14, the base material 11 has a first layer 111, a second layer 112, and a fifth layer 115, but does not have a third layer 113 and a sixth layer 116. Therefore, the first bonding layer 12 includes the first surface 11A of the base material 11. The fifth layer 115 includes the second surface 11B of the base material 11. Both the second layer 112 and the fifth layer 115 contain titanium.

[0068] Next, we will explain the effects and benefits of the bonding material A50.

[0069] The bonding material A50 comprises a base material 11 and a first bonding layer 12 laminated on the first surface 11A of the base material 11. The base material 11 contains a metal. The first bonding layer 12 contains a metal and an organic compound. The entire first bonding layer 12 is located on the opposite side of the base material 11 in the first direction z, with respect to the first surface 11A. Therefore, this configuration makes it possible to reduce the manufacturing cost of the bonding material A50 without causing a decrease in the heat dissipation performance of the bonding material A50. Furthermore, by having a configuration common to bonding material A10, bonding material A50 achieves the same effects as bonding material A10.

[0070] In bonding material A50, the base material 11 has a second layer 112 but no third layer 113. Even in this case, the first bonding layer 12 is laminated on the second layer 112. In addition, the first layer 111 and the second layer 112 contain different metals. Therefore, by adopting this configuration, peeling of the first bonding layer 12 from the base material 11 can be prevented, similar to the effects of bonding material A10.

[0071] This disclosure is not limited to the embodiments described above. The specific configuration of each part of this disclosure can be modified in various ways.

[0072] This disclosure includes embodiments described in the following appendices: Appendix 1. A bonding material comprising: a base material having a first surface facing one side in a first direction; and a first bonding layer laminated on the first surface, wherein the base material contains a metal; the first bonding layer contains a metal and an organic compound; and the entire first bonding layer is located on the opposite side from the base material with respect to the first surface in the first direction. Appendix 2. The bonding material according to Appendix 1, wherein the base material has a first layer and a second layer located between the first layer and the first bonding layer, each of the first layer and the second layer contains a different metal; and the dimension of the second layer in the first direction is smaller than the dimension of the first layer in the first direction. Appendix 3. The bonding material according to Appendix 2, wherein the Young's modulus of the metal contained in the first layer is lower than the Young's modulus of the metal contained in the first bonding layer. Appendix 4. The bonding material according to Appendix 3, wherein the second layer contains the first surface and contains titanium. Appendix 5. The bonding material according to Appendix 3, wherein the base material has a third layer located between the second layer and the first bonding layer, the third layer contains a metal different from the metal contained in the first layer, and the dimension of the third layer in the first direction is smaller than the dimension of the first layer in the first direction. Appendix 6. The bonding material according to Appendix 5, wherein the third layer includes the first surface. Appendix 7. The bonding material according to Appendix 6, wherein the second layer contains nickel and the third layer contains copper. Appendix 8. The bonding material according to Appendix 6, wherein the metal contained in the third layer is the same as the metal contained in the first bonding layer. Appendix 9. The bonding material according to Appendix 8, wherein the second layer contains titanium, and each of the first bonding layer and the third layer contains silver. Appendix 10. The bonding material according to Appendix 8, wherein the second layer contains nickel, and each of the first bonding layer and the third layer contains silver. Appendix 11. The bonding material according to Appendix 10, wherein the base material has a fourth layer located between the second layer and the third layer, the fourth layer contains metal, and the dimension of the fourth layer in the first direction is smaller than the dimension of the first layer in the first direction. Appendix 12. The bonding material according to Appendix 11, wherein the fourth layer contains copper.Note 13. The bonding material according to any one of Notes 1 to 12, wherein the dimension of the first bonding layer in the first direction is smaller than the dimension of the base material in the first direction. Note 14. The bonding material according to Note 13, further comprising a second bonding layer containing a metal and an organic compound, wherein the base material has a second surface facing the opposite side of the first surface in the first direction, the second bonding layer is laminated on the second surface, the entirety of the second bonding layer is located on the opposite side of the base material with respect to the second surface in the first direction, and the dimension of the second bonding layer in the first direction is smaller than the dimension of the base material in the first direction. Note 15. The bonding material according to Note 14, wherein the first bonding layer and the second bonding layer are made of the same material. Note 16. The bonding material according to Note 13, further comprising a protective layer covering the first bonding layer. Note 17. A semiconductor device comprising: a bonding material as described in Appendix 14; a substrate; a semiconductor element mounted on the substrate on one side of the substrate in the first direction; a sealing resin covering the semiconductor element; and a heat dissipation member located on the opposite side from the semiconductor element with respect to the substrate, wherein the substrate is exposed from the sealing resin, and the bonding material bonds the heat dissipation member and the substrate. Appendix 18. A method for manufacturing a bonding material, comprising the step of arranging a first bonding layer containing a metal and an organic compound on one side of a base material containing a metal in the first direction, wherein in the step of arranging the first bonding layer, the material of the first bonding layer containing an organic solvent and being in paste form is applied to the base material, and the material is dried so that the organic solvent remains. Appendix 19. A method for manufacturing a bonding material, comprising the step of arranging a first bonding layer containing a metal and an organic compound on one side of a base material containing a metal in the first direction, wherein in the step of arranging the first bonding layer, the first bonding layer, which is in a solid-liquid mixture state and maintains its shape, is pressed onto the base material. Appendix 20. A method for manufacturing a bonding material according to Appendix 18 or 19, comprising the step of arranging a second bonding layer containing a metal and an organic compound on the other side of the base material in the first direction, wherein the method for arranging the second bonding layer is the same as the method for arranging the first bonding layer. Appendix 21. A bonding material according to Appendix 3, wherein the first layer contains aluminum, and the first bonding layer contains silver.

[0073] A10-A50: bonding material, B: semiconductor device, 11: base material, 11A, 11B: first surface, second surface, 111-117: first to seventh layers, 12, 13: first bonding layer, second bonding layer, 19: protective layer, 21: substrate, 211: insulating layer, 212, 213: first conductive layer, second conductive layer, 214: heat dissipation layer, 22, 23, 24: first power terminal, second power terminal, third power terminal, 31, 32: first semiconductor element, second semiconductor element, 41, 42: first conductive member, second conductive member, 50: sealing resin, 70: heat dissipation member, 71: base, 72: heat dissipation part, z, x, y: first direction, second direction, third direction

Claims

1. A bonding material comprising: a base material having a first surface facing one side in a first direction; and a first bonding layer laminated on the first surface, wherein the base material contains a metal, the first bonding layer contains a metal and an organic compound, and the entirety of the first bonding layer is located on the opposite side from the base material with respect to the first surface in the first direction.

2. The bonding material according to claim 1, wherein the base material comprises a first layer and a second layer located between the first layer and the first bonding layer, each of the first layer and the second layer comprising different metals, and the dimension of the second layer in the first direction being smaller than the dimension of the first layer in the first direction.

3. The bonding material according to claim 2, wherein the Young's modulus of the metal contained in the first layer is lower than the Young's modulus of the metal contained in the first bonding layer.

4. The bonding material according to claim 3, wherein the second layer includes the first surface and contains titanium.

5. The bonding material according to claim 3, wherein the base material has a third layer located between the second layer and the first bonding layer, the third layer contains a metal different from the metal contained in the first layer, and the dimension of the third layer in the first direction is smaller than the dimension of the first layer in the first direction.

6. The bonding material according to claim 5, wherein the third layer includes the first surface.

7. The bonding material according to claim 6, wherein the second layer contains nickel and the third layer contains copper.

8. The bonding material according to claim 6, wherein the metal contained in the third layer is the same as the metal contained in the first bonding layer.

9. The bonding material according to claim 8, wherein the second layer contains titanium, and each of the first bonding layer and the third layer contains silver.

10. The bonding material according to claim 8, wherein the second layer contains nickel, and each of the first bonding layer and the third layer contains silver.

11. The bonding material according to claim 10, wherein the base material has a fourth layer located between the second layer and the third layer, the fourth layer contains metal, and the dimension of the fourth layer in the first direction is smaller than the dimension of the first layer in the first direction.

12. The bonding material according to claim 11, wherein the fourth layer comprises copper.

13. The bonding material according to any one of claims 1 to 12, wherein the dimension of the first bonding layer in the first direction is smaller than the dimension of the base material in the first direction.

14. The bonding material according to claim 13, further comprising a second bonding layer containing a metal and an organic compound, wherein the base material has a second surface facing opposite to the first surface in the first direction, the second bonding layer is laminated on the second surface, the entirety of the second bonding layer is located opposite to the base material with respect to the second surface in the first direction, and the dimensions of the second bonding layer in the first direction are smaller than the dimensions of the base material in the first direction.

15. The bonding material according to claim 14, wherein the first bonding layer and the second bonding layer are made of the same material.

16. The bonding material according to claim 13, further comprising a protective layer covering the first bonding layer.

17. A semiconductor device comprising: a bonding material according to claim 14; a substrate; a semiconductor element mounted on the substrate on one side of the substrate in the first direction; a sealing resin covering the semiconductor element; and a heat dissipation member located on the opposite side from the semiconductor element with respect to the substrate, wherein the substrate is exposed from the sealing resin, and the bonding material bonds the heat dissipation member and the substrate.

18. A method for manufacturing a bonding material, comprising the step of arranging a first bonding layer containing a metal and an organic compound on one side in a first direction of a base material containing a metal, wherein in the step of arranging the first bonding layer, the material of the first bonding layer, which contains an organic solvent and is in paste form, is applied to the base material, and the material is dried so that the organic solvent remains.

19. A method for manufacturing a bonding material, comprising the step of arranging a first bonding layer containing a metal and an organic compound on one side in a first direction of a base material containing a metal, wherein in the step of arranging the first bonding layer, the first bonding layer, which is in a solid-liquid mixture state and maintains its shape, is pressed against the base material.

20. A method for manufacturing a bonding material according to claim 18 or 19, comprising the step of arranging a second bonding layer containing a metal and an organic compound on the other side of the base material in the first direction, wherein the method for arranging the second bonding layer is the same as the method for arranging the first bonding layer.

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