Method for manufacturing power conversion device, and power conversion device

Abstract

Provided is a method for manufacturing a power conversion device in which a plurality of power modules and a heat dissipation member corresponding to the plurality of power modules are thermally connected via a plate-shaped insulating member, the method comprising: a first bonding step for forming a plurality of first assemblies by using a first bonding layer to bond the insulating member and the heat dissipation member, and for attaching the plurality of first assemblies to a cooling flow path member that forms a flow path wall of a flow path through which a refrigerant for dissipating heat from the power modules flows; and a second bonding step, which follows the first bonding step, for using a second bonding layer to bond the insulating member and the power modules.

Description

Method for manufacturing a power conversion device, and power conversion device

[0001] The present invention relates to a method for manufacturing a power converter and to a power converter.

[0002] Power conversion devices that perform power conversion by switching power semiconductor elements have high conversion efficiency and are therefore widely used in consumer applications, automotive applications, railway applications, substation facilities, etc. As an example of the configuration of such a power conversion device, Patent Document 1 listed below discloses a configuration in which adhesive layers are provided between a water channel, which is a heat dissipation member, and an insulating member, and between the insulating member and a power module.

[0003] Japanese Patent Application Laid-Open No. 2005-93593

[0004] In the technology described in Patent Document 1, if there is variation in the thickness of each power module, the plate-shaped insulating member provided between the power module and the heat dissipation member may tilt with respect to the surface of the heat dissipation member, causing the problem of peeling due to thermal stress. Furthermore, if the adhesive layer provided between the insulating member and the power module is made thicker to eliminate variation during the assembly process, this will result in reduced reliability due to thermal resistance and reduced heat dissipation.

[0005] A method for manufacturing a power conversion device in which a plurality of power modules and heat dissipation members corresponding to the plurality of power modules are thermally connected via a plate-shaped insulating member, the method comprising: forming a plurality of first assemblies by bonding the insulating member and the heat dissipation members with a first adhesive layer; performing a first bonding process to assemble the plurality of first assemblies to a cooling flow path member that forms a flow path wall of a flow path through which a refrigerant flows for dissipating heat from the power modules; and performing a second bonding process after the first bonding process to bond the insulating member and the power modules with a second adhesive layer.

[0006] According to the present invention, it is possible to provide a method for manufacturing a power converter and a power converter that achieves improved reliability, productivity, and heat dissipation.

[0007] FIG. 1 is an overall view of a power converter of the present invention. FIG. 2 is an AA' cross-sectional view of FIG. 1. FIG. 3 is a BB' cross-sectional view of FIG. 1. FIG. 4 is a cross-sectional view illustrating a first bonding step in the manufacturing method for a power converter of the present invention. FIG. 5 is a cross-sectional view illustrating a first bonding step in the manufacturing method for a power converter of the present invention. FIG. 6 is a cross-sectional view illustrating a second bonding step in the manufacturing method for a power converter of the present invention. FIG. 7 is a flowchart illustrating an inspection step in the manufacturing method for a power converter of the present invention.

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The following description and drawings are examples for explaining the present invention, and some omissions and simplifications have been made as appropriate for clarity of explanation. The present invention can be implemented in various other forms. Unless otherwise specified, each component may be singular or plural.

[0009] In order to facilitate understanding of the invention, the position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc. Therefore, the present invention is not necessarily limited to the position, size, shape, range, etc. disclosed in the drawings.

[0010] (Overall Configuration of Power Converter of the Present Invention) (FIGS. 1 to 3) The power converter 1 has a plurality of power modules 101 which are semiconductor devices including semiconductor elements (not shown), and cooling flow path members 107 which form flow path walls of cooling flow paths 107a through which a coolant flows for dissipating heat from the plurality of power modules 101 on both sides of the plurality of power modules 101. The configuration of the power converter 1 shown in the cross-sectional views of FIG. 2 and FIG. 3 is one example, but the power converter 1 has a total of 24 power modules 101 arranged in four rows in the short side direction and six rows in the long side direction.

[0011] The cooling flow path member 107 is configured so that only one cooling flow path member 107 on one surface can accommodate the multiple power modules 101. The cooling flow path member 107 has six rows of elastic biasing portions 301 in the longitudinal direction, corresponding to the multiple power modules 101 arranged in four rows in the lateral direction.

[0012] Heat dissipation members 105 corresponding to the plurality of power modules 101 are arranged between each power module 101 and each elastic biasing portion 301 of the cooling flow path member 107. The heat dissipation members 105 are formed in the cooling flow path member 107 so as to correspond to the plurality of power modules 101 arranged in four rows in the short side direction.

[0013] The power module 101 is molded by sealing each component, such as a semiconductor element and a conductor plate (not shown), with a sealing resin, and is cooled by bringing the surface of the heat dissipation member 105 into contact with the surface of the conductor plate exposed from the sealing resin.

[0014] The heat dissipation member 105 has pin-shaped heat dissipation fins 105a on the cooling flow path 107a side. The elastic biasing portion 301 is in contact with the heat dissipation fins 105a. The space formed by the elastic biasing portion 301 and the heat dissipation member 105 is the cooling flow path 107a, which is a flow path for circulating the refrigerant that flows in from a flow path inlet / outlet (not shown), and the heat dissipation fins 105a are arranged in the cooling flow path 107a.

[0015] Since the power conversion device 1 is double-sided cooled, the refrigerant flows from the cooling channel 107a formed on one side through piping components (not shown) to the cooling channel 107a formed on the opposite side. The refrigerant flowing through the cooling channel 107a is water or an antifreeze solution made by mixing ethylene glycol with water.

[0016] The cooling flow path member 107 is fastened by screws 111 to the four corners in the planar direction of the area where the multiple elastic biasing portions 301 are provided. This ensures a pressure force for applying pressure to each elastic biasing portion 301 corresponding to each power module 101, and also improves the adhesion reliability of the elastic biasing portions 301 to the heat dissipation member 105.

[0017] A plate-shaped insulating member 103 is disposed between the power module 101 and the heat dissipation member 105. The insulating member 103 thermally connects the power module 101 and the heat dissipation member 105. The insulating member 103 and the heat dissipation member 105 are bonded to each other by a first adhesive layer 104. The insulating member 103 and the power module 101 are bonded to each other by a second adhesive layer 102. Both ends of the insulating member 103 in the short direction of the power conversion device 1 are covered with the first adhesive layer 104 by pressure fixing in a manufacturing process described below.

[0018] In this way, the insulating member 103 is protected by the first adhesive layer 104, and crack damage and the like can be prevented from occurring in the insulating member 103 during the manufacturing process or during reliability tests due to thermal stress. The first adhesive layer 104 and the second adhesive layer 102 are thermally conductive adhesive layers, and are, for example, silicone or epoxy adhesive layers containing zinc oxide or alumina powder filler, or other adhesive layers whose main component is resin, or metal bonding materials such as solder or brazing filler. The insulating member 103 is, for example, an alumina plate, an alumina zirconia plate, or a silicon nitride plate, and has a thermal conductivity of 0.5 W / mK or higher.

[0019] (Manufacturing Method of Power Conversion Device) (FIGS. 4 and 5) A first bonding step in the manufacturing method of the power conversion device 1 of the present invention will be described. The first bonding step is a step of forming a first assembly 110 by bonding the insulating member 103 to the heat dissipation member 105 using the first adhesive layer 104, and assembling the assembly 110 to each elastic biasing portion 301 of the cooling channel member 107.

[0020] 4A, the heat dissipation member 105 has a positioning portion 109 for installing a positioning pin 201. The positioning portion 109 is a recess formed to fit the diameter of the positioning pin 201 that is temporarily connected to the heat dissipation member 105 in order to define an area on the heat dissipation member 105 where the insulating member 103 is to be installed. First, the positioning pin 201 is installed in this positioning portion 109. The positioning pin 201 may be made of metal or resin.

[0021] 4(b), the first adhesive layer 104 is applied to the protruding portions 105c on the heat dissipation member 105 where the insulating member 103 is to be installed. Then, the insulating member 103, which has a width that fits within the range of the positioning pins 201 installed on the heat dissipation member 105, is mounted on the protruding portions 105c between the positioning pins 201. Note that it is sufficient to have at least three positioning pins 201 on the heat dissipation member 105, but from the viewpoint of stability during installation, it is preferable to have four or more positioning pins 201.

[0022] 4(c), pressure is applied from above the insulating member 103 using a press machine 202 or the like so that the insulating member 103 is covered with the first adhesive layer 104 and so that the first adhesive layer 104 has a specified thickness. Note that to prevent cracks from occurring in the insulating member 103 due to excessive pressure, an upper limit is set on the amount of pressure, and the range of the amount of pressure is, for example, 0.1 MPa to 2 MPa. Furthermore, the amount of pressure may not be specified at just one level, but may be specified at two or more levels so that pressure is applied in two or more stages.

[0023] 4( d ), the press machine 202 is moved away from the insulating member 103, and the positioning pins 201 are removed from the positioning portions 109. Because the positioning pins 201 were provided on the heat dissipation member 105 while it was being pressed by the press machine 202, even when the positioning pins 201 were removed after pressing, the first adhesive layer 104, which has been deformed by pressure, does not flow into the positioning portions 109. In this way, a plurality of first assemblies 110 are formed in which the insulating member 103 and the heat dissipation member 105 are bonded to each other by the first adhesive layer 104.

[0024] The flow path plane 105b of the heat dissipation member 105 is formed with approximately the same area as the heat dissipation surface of the power module 101. This reduces the bending stress applied to the insulating member 103, and suppresses cracks in the insulating member 103, thereby improving reliability.

[0025] It is desirable that the angle formed by the least-squares plane on the flow path plane 105b of the heat dissipation member 105 and the least-squares plane on the surface of the insulating member 103 be 10 degrees or less. This makes it possible to prevent the plane of the insulating member 103 from being misaligned with the flow path plane 105b of the heat dissipation member 105. Furthermore, if the main component of the first adhesive layer 104 is a thermosetting resin, a necessary heat treatment may be performed in a constant temperature bath or the like to harden the resin.

[0026] 5A shows the cooling channel member 107 formed in FIG. 4D without the first assembly 110 mounted thereon. In the cooling channel member 107, a plurality of elastic biasing portions 301 are locations where the first assembly 110 is mounted.

[0027] 5B, when the first assembly 110 is mounted on the cooling channel member 107, a plurality of sealing members 106 are applied to connect the cooling channel 107 and the plurality of assemblies 110. The sealing members 106 are made of an adhesive, a rubber elastic material, a wax material, or the like, and are made of a material that can be deformed when the first assembly 110 is mounted on the cooling channel member 107 and pressurized.

[0028] 5(c), multiple first assemblies 110 are mounted in the openings 107b of the elastic biasing portions 301, and each first assembly 110 is brought into close contact with the sealing member 106, and the first assemblies 110 are pressed toward the cooling channel member 107. As a result, six rows of first assemblies 110 aligned in the longitudinal direction of the cooling channel member 107 are assembled to the cooling channel member 107, and fixed by curing the sealing member 106. This completes the first bonding step.

[0029] After the first bonding process is completed, an inspection process is carried out according to the procedure shown in FIG. 7, which will be described later, before the second bonding process is started. This inspects the adhesive state of the first adhesive layer 104, and determines whether the power module 101 to be mounted in the second bonding process can be properly mounted on the first assembly 110 assembled to the cooling channel member 107. This improves the reliability and heat dissipation of the power conversion device 1. After the inspection process is completed, the second bonding process is started.

[0030] (FIG. 6) The second bonding step will be described. First, FIG. 6(a) shows the state in FIG. 5(c) in which the first assembly 110 is pressurized and assembled to the cooling channel member 107. This state is referred to as the second assembly 110a. In FIG. 6(b), in the second assembly 110a, the second adhesive layer 102 is applied to the insulating members 103 of the first assembly 110 using an applicator (not shown).

[0031] In addition, when applying the second adhesive layer 102, the first adhesive layer 104 is thermally cured to sufficiently adhere to the insulating member 103 and the heat dissipation member 105, thereby preventing the insulating member 103 from shifting position during the application operation of the second adhesive layer 102, and contributing to the stable manufacture of the power conversion device 1.

[0032] 6(c), a plurality of power modules 101 mounted on a printed circuit board 108 are mounted and bonded to the positions on each insulating member 103 where the second adhesive layer 102 has been applied. By applying pressure to the power modules 101 from above with a press (not shown), the second adhesive layer 102 spreads in the planar direction, tightly adhering the power modules 101 and the insulating member 103 and thermally connecting the power modules 101 and the heat dissipation member 105 via the insulating member. This completes the second bonding process.

[0033] The power modules 101 are arranged on the printed circuit board 108 with the lower surfaces of the power modules 101 aligned with a predetermined reference plane in the stacking direction. This allows the lower surfaces of the power modules 101 to be set at a uniform height, allowing multiple power modules 101 to be arranged stably.

[0034] After the second bonding step is completed, in Fig. 6(d), a second adhesive layer 102 is applied onto the power module 101. In Fig. 6(e), a product identical to the second assembly 110a created in Fig. 6(a) is mounted so that the insulating member 103 of the second assembly 110a and the second adhesive layer 102 are bonded to each other.

[0035] The cooling channel members 107 on both sides in the stacking direction are then fastened with bolts and nuts (not shown). As a result, the adhesive surfaces of the first adhesive layer 104 and the second adhesive layer 102 are expanded by pressure, and can cover the insulating member 103, thereby contributing to the prevention of cracks in the insulating member 103. The power conversion device 1 is manufactured through the above steps.

[0036] In addition, since the second adhesive layer 102 absorbs tolerances due to variations in thickness of the multiple power modules 101, the second adhesive layer 102 needs to be thickened in areas where the thickness of one power module 101 is relatively smaller than the thickness of the other power modules 101. This makes it difficult to apply compressive stress, which may cause a decrease in reliability and a decrease in heat dissipation due to thermal stress.

[0037] To avoid this, when the first adhesive layer 104 and the second adhesive layer 102 are both made of resin, the second adhesive layer 102 is made to contain a higher amount of metal filler and a lower amount of resin than the first adhesive layer 104. By separating the materials in this manner, the thermal conductivity of the second adhesive layer 102 can be made higher than that of the first adhesive layer 104, thereby maintaining good thermal conduction between the power module 101, the insulating member 103, and the heat dissipation member 105. This also results in a higher shear force of the first adhesive layer 104 than that of the second adhesive layer 102, but it is desirable for the second adhesive layer 102 to have a high thermal conductivity even if the shear force is small, and this can also improve the fixation between the insulating member 103 and the heat dissipation member 105 in the first assembly 110.

[0038] (Inspection Process) (FIG. 7) The procedure for the inspection process carried out between the first bonding process and the second bonding process will be described. First, after the first bonding process is completed, in step S701, the void fraction of the first adhesive layer 104 is measured. Note that the void fraction of the first adhesive layer 104 may be measured using, for example, X-ray transmission measurement or ultrasonic flaw detection measurement.

[0039] In step S702, it is determined whether the measured void fraction of the first adhesive layer 104 is lower than a first specified value. If the void fraction of the first adhesive layer 104 is equal to or greater than the first specified value (NO), the product is determined to be defective with reduced reliability in step S709, and the inspection process flow ends. If the void fraction of the first adhesive layer 104 is lower than the first specified value (YES), the product is determined to be non-defective, and the process proceeds to step S703. The specified value in step 702 is, for example, a void fraction of 5%.

[0040] In step S703, a first thickness T1, which is the thickness of the first adhesive layer 104 in the first assembly 110, is obtained. Subsequently, in step S704, it is determined whether the first thickness T1 is lower than a second specified value. If the first thickness T1 is equal to or greater than the second specified value (NO), the product is determined to be a defective product with reduced reliability in step S703, and the inspection process flow ends. If the first thickness T1 is lower than the second specified value (YES), the process proceeds to step S705.

[0041] In step S705, a second thickness T2, which is the maximum thickness among the thicknesses of the multiple power modules 101 to be installed on the heat dissipation member 105, is obtained. In step S706, it is determined whether the sum T1 + T2 of the first thickness T1 and the second thickness T2 is lower than a third specified value. If the sum T1 + T2 is lower than the third specified value (YES), the process proceeds to step S707. If the sum T1 + T2 is equal to or greater than the third specified value (NO), the process proceeds to step S708.

[0042] The thickness of the first adhesive layer 104 and the power module 101 may be measured using, for example, a laser beam, a micrometer, an interference fringe measuring device, or the like.

[0043] In step S707, the mounting of the power module 101 onto the second assembly 110a is permitted, and the second bonding step of Fig. 6 is performed. On the other hand, in step S708, the mounting of the power module 101 onto the second assembly 110a is prohibited.

[0044] By carrying out the inspection process in this manner, it is possible to proceed to the second bonding process after confirming that the thickness of the first adhesive layer 104 is roughly uniform through the pressurizing process and that the plane of the insulating member 103 and the flow path plane 105b of the heat dissipation member 105 are roughly parallel. Furthermore, the first adhesive layer 104 is smaller than conventionally, improving heat dissipation, and further, since compressive stress is more easily applied to the first adhesive layer 104 and the second adhesive layer 102 for each power module 101, not only can the second adhesive layer 102 absorb thickness tolerances (variations), but reliability and productivity can also be improved.

[0045] According to the embodiment of the present invention described above, the following advantageous effects are achieved.

[0046] (1) A manufacturing method of a power conversion device 1 in which a plurality of power modules 101 and heat dissipation members 105 corresponding to the plurality of power modules 101 are thermally connected via a plate-shaped insulating member 103, the method comprising: forming a plurality of first assemblies 110 by bonding the insulating member 103 and the heat dissipation member 105 with a first adhesive layer 104; performing a first bonding process to assemble the plurality of first assemblies 110 to a cooling channel member 107 that forms a channel wall of a channel through which a coolant flows for dissipating heat from the power modules 101; and performing a second bonding process to bond the insulating member 103 and the power modules 101 with a second adhesive layer 102 after the first bonding process. In this way, by adopting a manufacturing method that separates the first bonding process from the second bonding process, it is possible to provide a power conversion device 1 that achieves improved reliability, improved productivity, and improved heat dissipation.

[0047] (2) After the first bonding step, and before the second bonding step is started, an inspection step is performed to inspect the bonding state of the first adhesive layer 104. In this way, it is possible to provide a power conversion device 1 that achieves improved reliability, improved productivity, and improved heat dissipation.

[0048] (3) In the inspection process, it is determined whether the void fraction of the first adhesive layer 104 is lower than a first specified value, and if the void fraction is lower than the first specified value, it is determined whether the first thickness T1, which is the thickness of the first adhesive layer 104, is lower than a second specified value, and if the first thickness T1 is lower than the second specified value, it is determined whether the sum of the first thickness T1 and the second thickness T2, which is the maximum thickness of the multiple power modules 101, is lower than a third specified value, and if the sum is lower than the third specified value, the second adhesive process is performed. In this way, it is possible to provide a power conversion device 1 that achieves improved reliability, improved productivity, and improved heat dissipation.

[0049] (4) The first adhesive layer 104 and the second adhesive layer 102 are mainly made of resin, which contributes to improving reliability and heat dissipation.

[0050] (5) In the first bonding step, pressure is applied so that the insulating member 103 is covered with the first adhesive layer 104. By doing so, the occurrence of cracks in the insulating member 103 can be suppressed.

[0051] (6) In the first bonding step, a positioning portion 109 is provided on the heat dissipation member 105 to define an arrangement area for the insulating member 103 on the heat dissipation member 105. In this way, the insulating member 103 can be appropriately arranged on the heat dissipation member 105.

[0052] (7) In the first bonding step, the angle formed by the least squares plane on the flow path side surface of the heat dissipation member 105 and the least squares plane on the surface of the insulating member 103 is set to 10 degrees or less. By doing so, it is possible to prevent the plane of the insulating member 103 from being misaligned with the flow path plane 105b of the heat dissipation member 105.

[0053] (8) The shear force of the first adhesive layer 104 is set to be higher than the shear force of the second adhesive layer 102. By doing so, the fixation between the insulating member 103 and the heat dissipation member 105 in the first assembly 110 can be improved.

[0054] (9) The thermal conductivity of the second adhesive layer 102 is set higher than the thermal conductivity of the first adhesive layer 104. By doing so, good thermal conduction can be maintained between the power module 101, the insulating member 103, and the heat dissipation member 105.

[0055] (10) The heat dissipation member 105 is provided with heat dissipation fins 105a on the flow path side, and the cooling flow path member 107 is provided with elastic biasing portions 301 on the surface that contacts the heat dissipation fins 105a, and in the first bonding step, the first assembly 110 is attached to the cooling flow path member 107 using the sealing member 106, and after the second bonding step, the heat dissipation member 105 is pressed against the power module 101. This allows the cooling flow path 107a to be formed, contributing to improved heat dissipation.

[0056] (11) A power conversion device 1 includes a plurality of power modules 101, a cooling channel member 107 forming a channel wall of a cooling channel 107a through which a refrigerant flows for dissipating heat from the plurality of power modules 101, heat dissipation members 105 arranged between the plurality of power modules 101 and the cooling channel member 107 and provided corresponding to each power module 101, and a plate-shaped insulating member 103 arranged between the power modules 101 and the heat dissipation member 105 and thermally connecting the power modules 101 and the heat dissipation member 105, wherein the insulating member 103 and the heat dissipation member 105 are bonded to each other by a first adhesive layer 104 to form a first assembly 110, and the insulating member 103 and the power modules 101 are bonded to each other by a second adhesive layer 102, and the first assembly 110 is assembled to the cooling channel member 107. By employing the manufacturing method for the power conversion device 1 of the present invention for such a power conversion device 1, a power conversion device 1 that achieves improved reliability, improved productivity, and improved heat dissipation can be provided.

[0057] The present invention is not limited to the above-described embodiments, and various modifications and combinations of other configurations are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to those having all of the configurations described in the above-described embodiments, and includes those in which some of the configurations are omitted.

[0058] REFERENCE SIGNS LIST 1 Power conversion device 101 Power module 102 Second adhesive layer 103 Insulating member 104 First adhesive layer 105 Heat dissipation member 105a Heat dissipation fin 105b Flow path plane 105c Projection 106 Sealing member 107 Cooling flow path member 107a Cooling flow path 107b Opening 108 Printed circuit board 109 Positioning portion 110 First assembly 110a Second assembly 111 Screw 201 Positioning pin 202 Press machine 301 Elastic biasing portion

Claims

1. A manufacturing method for a power conversion device in which a plurality of power modules and heat dissipation members corresponding to the plurality of power modules are thermally connected via a plate-shaped insulating member, the manufacturing method comprising: forming a plurality of first assemblies by bonding the insulating member and the heat dissipation member with a first adhesive layer; performing a first bonding process to assemble the plurality of first assemblies to a cooling flow path member that forms a flow path wall through which a coolant flows for dissipating heat from the power modules; and performing a second bonding process to bond the insulating member and the power modules with a second adhesive layer after the first bonding process.

2. The method for manufacturing a power conversion device according to claim 1, further comprising the step of: performing an inspection step of inspecting the adhesive condition of the first adhesive layer after the first adhesive step and before starting the second adhesive step.

3. A method for manufacturing a power conversion device as described in claim 2, wherein in the inspection process, it is determined whether a void rate of the first adhesive layer is lower than a first specified value, and if the void rate is lower than the first specified value, it is determined whether a first thickness which is the thickness of the first adhesive layer is lower than a second specified value, and if the first thickness is lower than the second specified value, it is determined whether a sum of the first thickness and a second thickness which is the maximum thickness of the plurality of power modules is lower than a third specified value, and if the sum is lower than the third specified value, the second adhesive process is performed.

4. The method for manufacturing a power conversion device according to claim 1, wherein the main component of the first adhesive layer and the second adhesive layer is resin.

5. The method for manufacturing a power conversion device according to claim 1, wherein in the first bonding step, pressure is applied so that the insulating member is covered with the first adhesive layer.

6. A method for manufacturing a power conversion device as described in claim 1, wherein in the first bonding step, a positioning portion is provided on the heat dissipation member to define a placement area on the heat dissipation member in which the insulating member is placed.

7. A method for manufacturing a power conversion device as described in claim 1, wherein in the first bonding process, the angle formed by a least-squares plane on the flow path side surface of the heat dissipation member and a least-squares plane on the surface of the insulating member is set to 10 degrees or less.

8. The method for manufacturing a power conversion device according to claim 1, wherein the shear strength of the first adhesive layer is made higher than the shear strength of the second adhesive layer.

9. The method for manufacturing a power conversion device according to claim 1, wherein the thermal conductivity of the second adhesive layer is made higher than the thermal conductivity of the first adhesive layer.

10. A method for manufacturing a power conversion device, comprising the steps of: providing a heat dissipation fin on the flow path side of the heat dissipation member; providing an elastic biasing portion on a surface of the cooling flow path member that contacts the heat dissipation fin; attaching the assembly to the cooling flow path member using a sealing member in the first bonding step; and pressurizing the heat dissipation member against the power module after the second bonding step.

11. A power conversion device comprising: a plurality of power modules; a cooling flow path member forming a flow path wall of a cooling flow path through which a refrigerant flows for dissipating heat from the plurality of power modules; heat dissipation members arranged between the plurality of power modules and the cooling flow path member and corresponding to each of the power modules; and a plate-shaped insulating member arranged between the power modules and the heat dissipation member and thermally connecting the power modules and the heat dissipation member, wherein the insulating member and the heat dissipation member are bonded to each other by a first adhesive layer to form a first assembly, and the insulating member and the power modules are bonded to each other by a second adhesive layer, and the first assembly is attached to the cooling flow path member.

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