Semiconductor device

Abstract

To improve reliability of a semiconductor device.SOLUTION: A power module 101 having a semiconductor element, a heat dissipation member 200 having one surface to which the power module 101 is fixed and the other surface on which a heat dissipation pin 203 is formed, a frame 109 having an opening portion and in which the heat dissipation member is disposed such that a heat dissipation portion protrudes from the opening portion, and a seal member 106 that seals a space between the heat dissipation member 200 and the frame 109 in a liquid-tight manner, the seal member being coupled to the frame 109 such that the heat dissipation pin 203 is disposed inside the seal member, A semiconductor device includes a cover 107 which forms a flow path 301 through which a refrigerant flows together with a heat dissipation member 200 and a frame 109, and a protrusion which is formed on at least one of the heat dissipation member 200 and the frame 109, protrudes toward the other, and is covered with a seal member 106.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a semiconductor device, and more particularly to a semiconductor device used in electric power equipment such as a power converter. [Background technology]

[0002] Power conversion devices that use power semiconductor elements as switching elements have high power conversion efficiency and are therefore widely used in consumer, automotive, railway, and substation equipment. For example, Patent Document 1 describes a semiconductor device including multiple power modules and used in the power conversion device. In the semiconductor device described in Patent Document 1, a heat dissipation fin material having heat dissipation fins formed on a heat dissipation base is disposed on the heat dissipation surface side of each of the multiple power modules. A frame having multiple openings is disposed so that the heat dissipation fins are inserted into the openings, and a sealing material is filled between the openings and the heat dissipation base to close the openings. Furthermore, a cover is provided that covers the heat dissipation base and frame to form a flow path through which a refrigerant flows. The power module is cooled by cooling fins disposed in the refrigerant flow path with the refrigerant. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-73861 Summary of the Invention [Problem to be solved by the invention]

[0004] To achieve both heat dissipation and reliability in a semiconductor device, it is desirable for the heat dissipation component to be made of a metal with high thermal conductivity, and for the cover and frame to be made of metal with high rigidity. However, if dissimilar metals come into contact with each other in the refrigerant, galvanic corrosion will occur.

[0005] In the semiconductor device described in Patent Document 1, depending on the processing accuracy and assembly accuracy of the heat dissipation member and the frame, there is a possibility that the heat dissipation member and the frame may come into contact with each other. Therefore, if different metals are used for the heat dissipation member and the frame, there is a concern that they may come into contact in the refrigerant, causing galvanic corrosion and reducing reliability.

[0006] The present invention has been made in view of the above-mentioned problems, and aims to suppress the occurrence of galvanic corrosion even when the frame and the heat dissipation member are made of different metals, thereby improving the reliability of the semiconductor device. [Means for solving the problem]

[0007] In one preferred embodiment, the semiconductor device according to the present invention comprises a power module having a semiconductor element, a heat dissipation member having the power module fixed to one surface and a heat dissipation portion formed on the other surface, a frame having an opening and in which the heat dissipation member is arranged so that the heat dissipation portion protrudes from the opening, a sealing member that liquid-tightly seals the space between the heat dissipation member and the frame, a cover that is joined to the frame so that the heat dissipation portion is arranged inside and that forms, together with the heat dissipation member and the frame, a flow path through which a refrigerant flows, and a protrusion formed on at least one of the heat dissipation member and the frame, protruding toward the other and covered by the sealing member. [Effects of the Invention]

[0008] According to the present invention, the heat dissipation component and frame of a semiconductor device are prevented from coming into contact in a refrigerant, and even when the frame and heat dissipation component are formed from different metal materials, the occurrence of galvanic corrosion is suppressed, thereby improving the reliability of the semiconductor device. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a perspective view illustrating a semiconductor device according to an embodiment. [Figure 2] FIG. 2 is a schematic cross-sectional view taken along dashed line AA' in FIG. [Figure 3]FIG. 2 is a schematic cross-sectional view taken along dashed line BB' in FIG. [Figure 4] FIG. 2 is a schematic diagram illustrating the appearance of a heat dissipation member according to an embodiment, as viewed from above. [Figure 5] FIG. 2 is a schematic diagram illustrating the appearance of a heat dissipation member according to an embodiment, as viewed from the side; [Figure 6] 10A and 10B are schematic external views showing modified examples of the heat dissipation member. [Figure 7] 10A and 10B are schematic external views showing other modified examples of the heat dissipation member. [Figure 8] FIG. 4 is an enlarged cross-sectional view of the area surrounded by the dashed line C in FIG. 3. [Figure 9] 1A to 1C are schematic diagrams illustrating a manufacturing process of a semiconductor device. [Figure 10] FIG. 10 is a schematic diagram showing a partial cross section of a semiconductor device according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the embodiments and drawings described below are examples for explaining the present invention, and some details have been omitted or simplified as appropriate for clarity of explanation. Please note that in order to facilitate understanding of the invention, the position, size, shape, range, etc. of each component shown in the drawings may not necessarily be accurately represented.

[0011] FIG. 1 is a perspective view showing a semiconductor device for a power converter according to one embodiment.

[0012] The semiconductor device 10 of this embodiment has a structure in which a plurality of power modules each including a semiconductor element are arranged on a printed circuit board 108 and are cooled from both sides. The semiconductor elements may be semiconductors such as silicon (Si) or silicon carbide (SiC), and may be semiconductor elements used as switching elements in a power converter for converting AC power to DC power. As will be described later, heat dissipation members are fixed to both sides of the power modules arranged on the printed circuit board 108, and the power modules are further covered from the outside by a cover 107. The heat dissipation members are arranged so as to fit into openings formed in a frame 109, and the cover 107 and the frame 109 are fastened together with screws at multiple locations.

[0013] The cover 107 has an elastic biasing member 110 formed at a location corresponding to the position where the power module is disposed, and the inner surface of the elastic biasing member 110 abuts against a pin-shaped heat dissipation member formed on the heat dissipation member. A flow path through which a refrigerant that cools the power module flows is formed between the elastic biasing member 110 and the heat dissipation member. The refrigerant flows in and out of a flow path inlet / outlet 300 (only one of two flow path inlets / outlets is visible in the figure) that leads to the flow path. The flow path on one side of the power module and the flow path on the other side are connected via piping components, and the refrigerant that flows in flows through both flow paths. For example, the refrigerant that flows in through the flow path inlet / outlet 300 enters the flow path covered by the upper cover 107 in the figure, flows from the upper left to the lower right in the figure, turns back via the piping component at the lower right end, flows through the flow path covered by the lower cover 107 toward the upper left in the figure, and flows out from another flow path inlet / outlet (not visible in the figure). The coolant can be, for example, water or an antifreeze solution made by mixing ethylene glycol into water. The power module is molded by sealing components such as semiconductor elements with resin, and cooling is achieved by transferring heat from the conductor plate exposed from the sealing resin to the heat dissipation member, and then releasing the heat from the heat dissipation member to the coolant flowing through the flow path.

[0014] Fig. 2 is a longitudinal cross-sectional view of the semiconductor device 10 taken along dashed line A-A' shown in Fig. 1. Fig. 3 is a width-wise cross-sectional view of the semiconductor device 10 taken along dashed line B-B' shown in Fig. 1. For simplification, Fig. 2 omits the illustration of the coolant inlet / outlet portion including the flow path inlet / outlet 300 located to the left of the dashed line.

[0015] The semiconductor device 10 has a configuration that is approximately symmetrical between the top and bottom of the figure, with the printed circuit board 108 sandwiched between them. The power module 101 is disposed in an opening formed in the printed circuit board 108, and is electrically connected to circuit wiring formed on the printed circuit board 108. The lower surface of the power module 101 is disposed so as to be aligned with a predetermined reference plane. By aligning the lower surfaces of the power modules 101 with a uniform reference plane, it becomes possible to arrange multiple power modules 101 for one heat dissipation member 200. In this embodiment, as shown in FIG. 3, four power modules 101 are disposed in the width direction of the semiconductor device 10, and one heat dissipation member 200 is disposed above and below them.

[0016] Plate-shaped insulating members 103 are bonded to the upper and lower surfaces of the power module 101 via adhesive layers 102. The insulating members 103 may be made of, for example, an alumina plate, an alumina-zirconia plate, or a silicon nitride plate. The insulating members 103 preferably have a thermal conductivity of 0.5 W / mK or higher. The insulating members 103 are further connected to the heat dissipation member 200 via adhesive layers 102. For example, a silicone adhesive or an epoxy adhesive containing a filler such as zinc oxide or alumina powder may be used for the adhesive layer 102. A metallic bonding material such as solder or brazing filler may also be used for the adhesive layer 102. By providing the adhesive layers 102 in this manner, good thermal conduction can be maintained between the power module 101 and the insulating members 103, and between the insulating members 103 and the heat dissipation member 200.

[0017] The heat dissipation member 200 is fixed to the power module 101 on one surface via two adhesive layers 102 and an insulating member 103. A plurality of heat dissipation pins 203 are formed as a heat dissipation portion on the side of the heat dissipation member 200 opposite to the surface fixed to the power module. In this embodiment, pin-shaped heat dissipation pins are used as the heat dissipation portion, but the heat dissipation portion can be any shape, such as a fin or plate, as long as it can increase the surface area of ​​the heat dissipation member 200 in contact with the refrigerant and enhance the heat dissipation effect. The heat dissipation member 200 can be formed using a metal material with high thermal conductivity, such as copper or aluminum. The thermal conductivity of the heat dissipation member 200 is preferably 200 W / mK or higher.

[0018] The heat dissipation member 200 is inserted into an opening formed in the frame 109, and the inner peripheral surface of the opening of the frame 109 faces the outer peripheral side surface of the base of the heat dissipation member 200. The periphery of the opening on one side of the frame 109 is arranged to face a flange formed on the outer periphery of the heat dissipation member 200 on the power module 101 side. The frame 109 is preferably made of a highly rigid metal material such as stainless steel or copper.

[0019] A sealing member 106 is filled between the heat dissipation member 200 and the frame 109. The sealing member 106 preferably has electrical insulation properties and elasticity. The sealing member 106 is made of, for example, a resin material.

[0020] The semiconductor device 10 is further covered on both the top and bottom sides in the figure with covers 107. As described above, the cover 107 is fixed to the frame 109 at multiple locations, for example, by screws. The portion of the cover 107 facing the heat dissipation member 200 is formed with an elastic biasing portion 110 that protrudes toward the heat dissipation member 200. The elastic biasing portion 110 is biased toward the heat dissipation member 200 so as to tightly contact the tip portions of the heat dissipation pins 203 via the elastic member 104. By providing the elastic member 104, even if the amount of deformation of the elastic biasing portion 110 is insufficient, the gap between the heat dissipation pins 203 and the elastic biasing portion 110 is filled, maintaining tight contact and improving cooling performance. The elastic member 104 is preferably formed of an insulating resin material.

[0021] It is desirable that cover 107 is formed of a highly rigid metallic material such as stainless steel or copper, similar to frame 109. By using a highly rigid material for cover 107 and frame 109, plastic deformation of cover 107 and frame 109 due to the biasing force on elastic biasing portion 110 can be suppressed, and adhesion between the tip of heat dissipation pin 203 and elastic biasing portion 110 can be maintained.

[0022] The space formed by the heat dissipation member 200, the cover 107, and the frame 109 becomes a flow path 301 through which the refrigerant flows. The heat dissipation fins 203 are arranged in the flow path 301, and the refrigerant flows between the heat dissipation fins 203. Heat generated in the power module 101 is transferred to the heat dissipation member 200 and dissipated from the heat dissipation fins 203 to the refrigerant in the flow path 301. In this way, the power module 101 is cooled from both sides by the refrigerant flowing through the flow path 301.

[0023] Here, if the heat dissipation member 200, the cover 107, and the frame 109 are made of different metals and have different natural potentials in the refrigerant, contact between the heat dissipation member 200 and the cover 107 or the frame 109 within the flow path 301 may cause galvanic corrosion, in which the metal with a lower potential corrodes due to battery action. In this embodiment, by interposing the elastic member 104 between the heat dissipation pin 203 and the elastic biasing member 110, direct contact between the heat dissipation pin 203 and the elastic biasing member 110 can be prevented, thereby suppressing the occurrence of galvanic corrosion. Furthermore, as will be described later, a protrusion provided between the heat dissipation member 200 and the frame 109 ensures a clearance between them, and the seal member 106 is filled therein. This prevents contact between the heat dissipation member 200 and the frame 109 within the flow path 301, thereby suppressing the occurrence of galvanic corrosion.

[0024] Fig. 4 is a schematic diagram showing the appearance of heat dissipation member 200 as seen from above. For convenience, in the following description, the front side of heat dissipation member 200 on the paper surface is referred to as the top and the back side of heat dissipation member 200 on the paper surface is referred to as the bottom. Fig. 5 is a schematic diagram showing the appearance of heat dissipation member 200 as seen from the side.

[0025] The heat dissipation member 200 has a plurality of heat dissipation pins 203 formed on the upper surface of a base portion 201. A flange portion 204 that extends outward from the base portion 201 is formed on the lower bottom surface of the base portion 201. When mounted on the semiconductor device 10, the flange portion 204 is positioned so that its outer peripheral portion faces one surface around the opening of the frame 109. A protrusion portion 202 is formed on each of the outer peripheral side surfaces of the base portion 201.

[0026] In this embodiment, the protrusion 202 has a partially spherical or ellipsoidal shape, and includes a curved portion that gradually moves away from the side surface of the base portion 201 as it goes from top to bottom. By providing the protrusion 202 with this shape, when the heat dissipation member 200 is placed on the frame 109, the frame 109 does not make uneven contact with the side surface of the base portion 201, and a clearance is secured between the side surface of the base portion 201 and the frame 109, allowing the heat dissipation member 200 to be placed on the frame 109 with precision.

[0027] The protrusion 202 can be formed by, for example, casting or grinding. The shape of the protrusion 202 is not limited to a partial sphere or ellipsoid as described above, and may be, for example, a protrusion 202a shaped like a lying cylinder as shown in Fig. 6, or a protrusion 202b having an inclined surface in which the distance from the side surface of the base portion 201 increases from top to bottom as shown in Fig. 7. The shape of the inclined surface is also not limited to a square as shown in the figure, and may be other shapes such as a trapezoid.

[0028] FIG. 8 is an enlarged cross-sectional view of the area surrounded by the dashed line C in FIG. 3, and in the figure, H1 to H4 indicate the dimensions of each part.

[0029] The height H1 of the protrusion 202, i.e., the distance from the surface of the flange 204 on the heat dissipation pin 203 side to the end of the protrusion 202 on the flow path 301 side, is smaller than the height H2 of the base 201, i.e., the distance from the same surface of the flange 204 to the surface of the base 201 on which the heat dissipation pin 203 is formed. The height H1 of the protrusion 202 is also larger than the distance H4 between the flange 204 and the frame 109 at the portion where the flange 204 and the frame 109 face each other, and is smaller than the sum of the thickness H3 of the frame 109 and the distance H4 between the flange 204 and the frame 109. In other words, the height H1 of the protrusion 202 from the flange 204 at the end on the flow path 301 side is H4

[0030] ​A seal member 106 is filled between the frame 109 and the base portion 201 and flange portion 204 of the heat dissipation member 200. The seal member 106 is filled so that the thickness in the vertical direction in the figure near the protrusion 202 is greater than H4. If possible, it is desirable that the thickness of the seal member 106 near the protrusion 202 is greater than the height H1 of the protrusion 202. By filling the seal member 106 in this manner, even if the frame 109 and the protrusion 202 come into contact, the contact area is covered with the seal member 106, and the refrigerant flowing through the flow path 301 can be prevented from reaching the contact area between the frame 109 and the protrusion 202.

[0031] 9A to 9C are schematic diagrams showing partial cross sections of the mounting portion of the power module 101 in a number of steps during the manufacturing process of the semiconductor device 10. FIG.

[0032] In step (A), the heat dissipation members 200 are arranged with the surface facing the power module 101 facing upward. In step (B), an adhesive is applied to the surface of the heat dissipation member 200 facing the power module to form an adhesive layer 102, and a plate-shaped insulating member 103 is mounted thereon. The insulating member 103 is pressed using a press or the like so that the adhesive layer 102 has a predetermined thickness. An upper limit is set for the amount of pressure applied, since excessive pressure may cause cracking and damage to the insulating member 103. The pressure is preferably applied at a pressure of 0.1 MPa to 2 MPa. The pressure makes the thickness of the adhesive layer 102 approximately uniform, and the insulating member 103 and the flow path plane are approximately parallel. The pressure does not need to be applied all at once; it may be applied multiple times so that the adhesive layer 102 finally has the predetermined thickness.

[0033] In step (C), sealing member 106 is applied to the portion of heat dissipation member 200 that spans base portion 201 and flange portion 204. At this time, a sufficient amount of sealing member 106 is applied so that protrusion 202 is covered with sealing member 106. For sealing member 106, an elastic insulating adhesive or rubber material is used, which is a material that can be deformed by stress due to pressure applied in the subsequent manufacturing process or pressure applied by elastic biasing portion 110.

[0034] In step (D), elastic member 104 is placed on the portion of cover 107 that faces the tip of heat dissipation pin 203, which is integrated with frame 109, and the assembly assembled up to step (C) is mounted on cover 107 through the opening of frame 109. At this time, pressure is applied to frame 109 and sealing member 106 so that they come into close contact, and if sealing member 106 is a thermosetting adhesive material, heat treatment is performed in a constant temperature bath.

[0035] In step (E), the power module 101 mounted on the printed circuit board 108 is bonded to the insulating member 103 via the adhesive layer 102.

[0036] In step (F), an adhesive layer 102 is formed on the surface of the power module 101 opposite to the surface bonded to the insulating member 103 in step (E), and another assembly assembled in steps (A) to (D) is mounted. Then, the covers 107 on both sides of the power module 101 are fastened together with bolts and nuts, and the semiconductor device 10 is assembled.

[0037] In step (D), when the assembled body is passed through the opening of the frame 109, the base portion 201 of the heat dissipation member 200 may come into contact with the frame 109. However, in this embodiment, the protrusions 202 formed on the base portion 201 allow for accurate positioning between the frame 109 and the base portion 201. This ensures a clearance between the frame 109 and the base portion 201, preventing the frame 109 and the base portion 201 from coming into contact with each other. Although the protrusions 202 may come into contact with the frame 109, the areas where the protrusions 202 and the frame 109 may come into contact are located in areas covered by the seal member 106 filled between the heat dissipation member 200 and the frame 109, preventing the contact area from being exposed to the refrigerant in the flow path 301. This prevents galvanic corrosion from occurring even when the protrusions 202 and the frame 109 come into contact with each other.

[0038] According to the first embodiment described above, the protrusions 202 formed on the heat dissipation member 200 ensure a clearance between the heat dissipation member 200 and the frame 109, thereby preventing the two from coming into contact with each other in the flow path 301. Furthermore, the areas where the protrusions 202 and the frame 109 may come into contact are covered by the seal member 106 and are not exposed in the flow path 301, preventing the contact areas from coming into contact with the refrigerant flowing in the flow path 301. This makes it possible to prevent the occurrence of galvanic corrosion and improve the reliability of the semiconductor device, and further makes it possible to improve the reliability of electric power equipment such as a power conversion device in which the semiconductor device is used.

[0039] 10 is a schematic diagram showing a partial cross section of a semiconductor device according to another embodiment. The semiconductor device of this embodiment differs from the above-described embodiment in the arrangement of protrusions formed between heat dissipation member 200 and frame 109. The other configuration of the semiconductor device is similar to that of semiconductor device 10 described with reference to FIGS. 1 to 3, and therefore, in the following, the same components will be referred to by the reference numerals used in the above-described embodiment, and duplicated explanations will be omitted.

[0040] The cross section shown in FIG. 10 , like FIG. 8 , is a cross section of a portion corresponding to the portion indicated by dashed line C in FIG. 3 . In this embodiment, instead of the protrusions 202 formed on the side surface of the base portion 201 of the heat dissipation member 200 in the previous embodiment, protrusions 150 are formed on the frame 109. Multiple protrusions 150 are formed on the inner circumferential surface of the opening of the frame 109 so as to surround the base portion 201. For example, if the opening is rectangular, each protrusion 150 is formed on each side of the opening so as to protrude from the frame 109 toward the base portion 201. It is desirable that the shape of the protrusions 150 be a partial sphere or ellipsoid protruding from the inner circumferential surface of the frame, such that the portion facing the base portion 201 has a curved surface. This shape allows the frame 109 and the heat dissipation member 200 to be easily aligned with high precision.

[0041] Furthermore, it is preferable that the position where the protrusion 150 is formed is closer to the flange 204 of the inner circumferential surface of the opening. The gap between the frame 109 and the heat dissipation member 200 is filled with the seal member 106 at a position higher than the tip of the protrusion 150, preferably enough to cover the protrusion. By forming the protrusion 150 on the side closer to the flange 204, the contact portion between the protrusion 150 and the heat dissipation member 200 is more reliably covered with the seal member 106, reducing the possibility that the contact portion will be exposed to the refrigerant in the flow path 301, and suppressing the occurrence of galvanic corrosion.

[0042] In this embodiment, as in the previously described embodiment, the possibility of the heat dissipation member coming into contact with the frame or cover within the refrigerant flow path is reduced, thereby suppressing the occurrence of galvanic corrosion and realizing a highly reliable semiconductor device.

[0043] In the above-described embodiment, one protrusion is formed on each side of the cooling member, but multiple protrusions may be provided on one side. Furthermore, the position where the protrusions are formed is not limited to the middle of the side of the cooling member, and they may be formed at a corner that spans two side faces. Furthermore, the flow path through which the coolant flows does not necessarily have to be provided on both sides of the module to be cooled, and may be provided on only one side.

[0044] While the present invention has been described above using representative embodiments as examples, the present invention is not limited to these and can be embodied in various forms without departing from the spirit of the invention as set forth in the claims. Furthermore, the above-described embodiments have been described in detail to make the present invention easier to understand, and the present invention is not necessarily limited to those having all of the described configurations. [Explanation of symbols]

[0045] 10: Semiconductor device 101: Power module 102: Adhesive layer 103: Insulating material 104: Elastic member 106: Sealing material 107: Cover 108: Printed circuit board 109: Frame 110: Elastic biasing portion 200: Heat dissipation material 201: Base section 202:Protrusion 203: Heat dissipation pin 204: Tsuba 300: Flow path entrance / exit 301: Flow path

Claims

1. a power module having a semiconductor element; a heat dissipation member having the power module fixed to one surface and a heat dissipation portion formed on the other surface; a frame having an opening, the heat dissipation member being disposed so that the heat dissipation portion protrudes from the opening; a sealing member that liquid-tightly seals the gap between the heat dissipation member and the frame; a cover coupled to the frame so that the heat dissipation unit is disposed inside the cover, the cover forming a flow path through which a refrigerant flows together with the heat dissipation unit and the frame; a plurality of protrusions formed on at least one of the heat dissipation member and the frame, protruding toward the other, and covered with the sealing member; A semiconductor device having:

2. 2. The semiconductor device according to claim 1, wherein the heat dissipation member and the frame are made of different metallic materials.

3. 3. The semiconductor device according to claim 2, wherein the heat dissipation member has a plurality of side surfaces facing the frame at the opening, and the plurality of protrusions are provided at least one at each of a plurality of positions corresponding to each of the plurality of side surfaces.

4. 3. The semiconductor device according to claim 2, wherein the protrusion is disposed closer to the power module than the surface of the seal member that comes into contact with the coolant flowing through the flow path.

5. 3. The semiconductor device according to claim 2, wherein the protrusion has a curved surface at a portion facing the other of the heat dissipation member and the frame.

6. 3. The semiconductor device according to claim 2, wherein the frame and the cover are made of a material having a higher rigidity than the heat dissipation member.

7. 3. The semiconductor device according to claim 2, wherein the heat dissipation member is made of a material having a higher thermal conductivity than the frame and the cover.

8. 3. The semiconductor device according to claim 2, wherein the heat sink and the cover are in contact with each other via an elastic member therebetween.

9. 9. The semiconductor device according to claim 8, wherein the sealing member and the elastic member are made of an electrically insulating material.

10. the heat dissipation member has a base portion fixed to the power module on one side and having the heat dissipation portion formed on the other side opposite to the side fixed to the power module, and a flange portion formed on an outer edge of the one side of the base portion and having a surface on the other side facing the frame, 3. The semiconductor device according to claim 2, wherein when the height from the other side surface of the flange to the end of the protrusion on the flow path side is H1, the height from the other side surface of the flange to the surface of the base on the heat dissipation side is H2, the height of the frame is H3, and the distance between the flange and the frame is H4, the relationships H4<H1<H2 and H4<H1<H4+H3 are satisfied.

Images