JP2020061399A - Cooler, base plate thereof, and semiconductor device - Google Patents

Abstract

To provide a cooler which has sufficient cooling performance and in which a base plate can be precisely fixed to a container body.SOLUTION: The present invention is directed to a cooler that comprises: a box-shaped container body 1 which has an opening in an upper surface; and a base plate 5 which has many heat radiation fins 61 formed on a lower surface side of an inner peripheral part 6, and also have a heat generation body which can be arranged on an upper surface side of the inner peripheral part 6. The base plate 5 is so assembled to the container body 1 as to close the upper surface opening 11 by fixing an outer peripheral part of the base plate 5 to an upper surface opening peripheral edge part of the container body 1 through a seal member 3 with the heat radiation fins 61 accommodated in the container body 1 through the upper surface opening 11. The base plate 5 is formed by forming the inner peripheral part 6 and an outer peripheral part 7 as different bodies and coupling the inner peripheral part 6 and the outer peripheral part 7 as the different bodies together into one body.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a cooler used for cooling a heating element such as a power semiconductor element and its base plate, and further to a semiconductor device including the cooler.

  BACKGROUND ART Power semiconductor elements used to control main power of electric motors such as hybrid vehicles (HVs) and electric vehicles (EVs), industrial machinery, home appliances, power driving equipment such as information terminals are large in size because they handle large amounts of electric power. It is accompanied by fever. For this reason, in order to avoid the adverse effects of high heat and maintain high performance, a cooler is bonded or adhered to the board (element mounting board) on which the power semiconductor elements are mounted, and the heat generated by the cooler is attached. Is to be released.

  If a large space for heat dissipation can be secured around the element mounting board, such as in stationary equipment, an air-cooled cooler can be used. When a large number of devices are densely arranged, it is customary to employ a liquid-cooled (water-cooled) cooler.

  The following Patent Documents 1 and 2 disclose liquid cooling type coolers for cooling the element mounting substrate. This cooler includes a box-shaped container body such as a water cooling jacket having an opening on the upper surface, and a base plate attached so as to close the upper surface opening of the container body. The base plate has a large number of heat radiation fins integrally formed on the lower surface side of the inner peripheral portion thereof, and the element mounting board mounted on the upper surface side of the inner peripheral portion. With the large number of heat radiation fins of the base plate accommodated in the container body through the upper opening, the outer peripheral portion of the base plate is fixed to the peripheral edge portion of the upper opening of the container body by a bolt or the like via a sealing member such as an O-ring. To be done. Thus, the container body and the base plate form a refrigerant flow path through which the refrigerant flows, and the refrigerant supplied from the outside of the cooler to one end of the refrigerant flow path flows out through the refrigerant flow path to the other end. Is configured. In this way, the refrigerant circulated in the refrigerant passage of the cooler and the semiconductor element exchange heat with each other through the base plate and the heat radiation fins, and the heat generated from the semiconductor element is released to the outside through the refrigerant. The semiconductor element is designed to be cooled by this.

JP, 2016-92209, A JP, 2008-66991, A

  In the cooler in which the container body and the base plate are separately attached afterwards, like the conventional coolers shown in Patent Documents 1 and 2, the inner peripheral portion of the base plate on which the heat radiation fins are formed has a cooling performance. While high thermal conductivity is required to improve the heat resistance, the outer peripheral part of the base plate must be sufficiently compressed to secure the sealing property when it is fixed to the container body. It is required to have high strength so as not to be deformed by the elastic repulsion of the member.

  However, in the conventional cooler, the entire base plate is integrally formed, and the inner peripheral portion of the base plate and the outer peripheral portion of the base plate are made of the same material. Therefore, if the base plate is made of a material having a high thermal conductivity in order to prioritize the cooling performance, it is not possible to obtain sufficient strength for the base plate, and the outer peripheral portion of the base plate is deformed by the repulsive force of the seal member, This causes a problem that it becomes difficult to attach the base plate to the container body with high accuracy. On the contrary, if the base plate is made of high-strength material, giving priority to the mounting accuracy of the base plate, the heat transfer coefficient of the inner peripheral part of the base plate will decrease and it will be difficult to obtain sufficient cooling performance. To do.

  The present invention has been made in view of the above problems, and in addition to being able to obtain sufficient cooling performance, a cooler that can attach a base plate to a container body in a stable state with high accuracy, and a base plate thereof. Another object is to provide a semiconductor device.

  In order to solve the above problems, the present invention includes the following means.

[1] A box-shaped container main body having an opening on the upper surface, and a base plate on which a large number of heat radiation fins are formed on the lower surface side of the inner peripheral portion, and a heating element can be arranged on the upper surface side of the inner peripheral portion By fixing the outer peripheral portion of the base plate to a peripheral edge portion of the upper surface opening of the container body via a seal member in a state where the heat radiation fin is accommodated in the container main body through the upper surface opening, A cooler in which a base plate is assembled to the container body so as to close an upper surface opening thereof,
The inner peripheral portion and the outer peripheral portion of the base plate are formed as separate bodies, and the inner peripheral portion and the outer peripheral portion of the separate body are connected and integrated. Cooler.

  [2] The cooler according to the above 1, wherein the outer peripheral portion of the base plate is formed of a material having high strength with respect to the inner peripheral portion.

  [3] The cooler according to the above 1 or 2, wherein the inner peripheral portion of the base plate is made of a material having a higher thermal conductivity than the outer peripheral portion.

  [4] The cooler according to any one of the aforementioned Items 1 to 3, wherein the outer peripheral portion of the base plate is formed thicker than the inner peripheral portion thereof.

  [5] The cooler according to any one of items 1 to 4, wherein the lower surface of the outer peripheral portion of the base plate and the lower surface of the inner peripheral portion are arranged in substantially the same plane.

[6] A concave step portion is provided below the inner peripheral edge of the outer peripheral portion of the base plate,
The cooler according to any one of the above items 1 to 5, wherein the cooler is arranged such that the outer peripheral edge of the inner peripheral portion is accommodated in the concave step portion.

[7] An inward protruding portion that protrudes inward is provided below the inner peripheral edge of the outer peripheral portion of the base plate, and
The cooler according to any one of the preceding items 1 to 5, wherein the outer peripheral edge of the inner peripheral portion is arranged in a state of being placed on the content protruding portion.

  [8] The cooler according to any one of the preceding items 1 to 7, wherein the outer peripheral portion and the inner peripheral portion of the base plate are made of aluminum.

[9] A base plate of a cooler, which is assembled to a box-shaped container body having an opening on the upper surface so as to close the upper opening,
On the lower surface side, a large number of fins that can be accommodated in the container body through the upper surface opening are formed, and on the upper surface side, an inner peripheral portion in which a heating element can be arranged,
An outer peripheral portion, which is provided outside the inner peripheral portion and can be fixed to a top opening edge portion of the container body via a seal member,
The inner peripheral portion and the outer peripheral portion are formed as separate bodies, and the inner peripheral portion and the outer peripheral portion of the separate body are connected and integrated to form a base for a cooler. Board.

[10] A box-shaped container body having an opening on the upper surface, a base plate having a large number of heat dissipation fins formed on the lower surface side of the inner peripheral portion, and a semiconductor element arranged on the upper surface side of the inner peripheral portion of the base plate. And the outer peripheral portion of the base plate is fixed to a peripheral edge of an upper opening of the container main body via a seal member in a state where the heat dissipation fin is accommodated in the container main body through an upper opening thereof. A semiconductor device in which the base plate is assembled to the container body so as to close an upper surface opening thereof,
The inner peripheral portion and the outer peripheral portion of the base plate are formed as separate bodies, and the inner peripheral portion and the outer peripheral portion of the separate body are connected and integrated. Semiconductor device.

  According to the cooler of the invention [1], since the inner peripheral portion in which the heat radiation fins are formed in the base plate and the outer peripheral portion fixed to the container body are separately formed, the inner peripheral portion and the outer peripheral portion are formed. And can be made of different materials. That is, the inner peripheral portion can be made of a material having high thermal conductivity, and the outer peripheral portion can be made of a material having high strength. As a result, the heat generated from the heating element is smoothly absorbed by the refrigerant in the container body through the inner peripheral portion, heat can be efficiently exchanged, and sufficient cooling performance can be obtained. Furthermore, the outer peripheral portion is not deformed by the elastic repulsive force of the seal member, and the outer peripheral portion can be securely attached to the container body in a state where the seal member is compressed. It can be installed in a stable state with good positional accuracy.

  According to the coolers of the inventions [2] to [4], the above effects can be obtained more reliably.

  According to the cooler of the inventions [5] and [6], it is possible to prevent a step from being formed between the inner peripheral portion and the outer peripheral portion on the lower surface side of the base plate, so that the refrigerant is cooled along the inner peripheral surface of the base plate. As a result, the cooling fluid can be smoothly flowed between the outer peripheral portion and the outer peripheral portion, and the cooling performance can be further improved.

  According to the cooler of the invention [7], since the inward protruding portion is formed on the inner peripheral edge of the outer peripheral portion and the outer peripheral edge of the inner peripheral portion is arranged on the inward protruding portion, By arranging the seal member at the position of the lower surface of the inward protruding portion, the seal member can be arranged at a position close to the upper opening of the container body. Therefore, the seal member can be arranged at a position closer to the inner side in the outer peripheral portion, and the outer diameter dimension of the outer peripheral portion can be reduced by that amount, which in turn can reduce the overall size and weight of the cooler.

  According to the cooler of the invention [8], the above effects can be obtained more reliably.

  According to the base plate of the cooler of the invention [9], since it has the same main part as described above, the same effect as described above can be obtained.

  According to the semiconductor device of the invention [10], since it has the same main part as described above, the same effect as described above can be obtained.

FIG. 1 is a sectional view showing a power semiconductor device to which a cooler according to a first embodiment of the present invention is applied. FIG. 2 is an enlarged sectional view showing the periphery of the joint between the inner peripheral portion and the outer peripheral portion of the base plate of the semiconductor device of the first embodiment. FIG. 3 is a sectional view showing a power semiconductor device to which a cooler according to a second embodiment of the present invention is applied. FIG. 4 is an enlarged cross-sectional view showing the periphery of the joint between the inner peripheral portion and the outer peripheral portion of the base plate of the semiconductor device of the second embodiment.

<First Embodiment>
FIG. 1 is a sectional view showing a power semiconductor device to which a cooler according to a first embodiment of the present invention is applied. 2 is an enlarged cross-sectional view of a main part of the semiconductor device, and corresponds to an enlarged cross-sectional view of a portion surrounded by a dashed line in FIG.

  As shown in FIG. 1, this semiconductor device includes a container body 1 such as a cooling jacket, a base plate 5, and a mounting substrate 2 as basic components.

  In the present specification and claims, the term aluminum is used to include not only pure aluminum but also aluminum alloys, unless otherwise specified. Further, in the present specification and claims, terms such as “upper (upper)” and “lower (lower)” indicating directions are not based on the direction of gravity, but are shown in FIG. 1 for convenience. It is based on the state. That is, the cooler and the semiconductor device of the present invention are in actual use, in addition to the state shown in FIG. 1, for example, a state in which the top and bottom are inverted with respect to the state in FIG. Alternatively, it may be used in a state where the upper and lower parts are arranged obliquely.

  The container body 1 is formed in a rectangular shape in a plan view, and is formed in a box shape (box shape) as a whole. The container body 1 has an opening 11 on the upper surface, and the inside of the container body 1 is opened upward by the upper surface opening 11.

  The outer peripheral shape of the base plate 5 is formed in a rectangular shape corresponding to the outer peripheral shape of the container body 1 in a plan view. The base plate 5 includes an inner peripheral portion 6 that constitutes an inner region of the base plate 5, and an outer peripheral portion 7 that constitutes an outer region of the base plate 5 and is arranged outside the inner peripheral portion 6. ing. In the present embodiment, the base plate 5 is formed separately from the inner peripheral portion 6 and the outer peripheral portion 7, and is made of different materials as described later.

  A large number of heat radiation fins 61 are integrally formed on the lower surface of the inner peripheral portion 6 so as to project downward. In the present embodiment, the structure of the heat radiation fin 61 is not particularly limited, and may be a plate fin or a pin fin. Further, when the pin fin is adopted, the cross-sectional shape is not limited, and it may be formed in any cross-sectional shape such as a circular shape, an elliptical shape, an oval shape, a polygonal shape, and an irregular shape.

  The outer peripheral portion 7 is formed to have a larger plate thickness than the inner peripheral portion 6. Further, as shown in FIGS. 1 and 2, an inward protruding portion 75 is integrally formed below the inner peripheral edge of the outer peripheral portion 7 so as to protrude inward.

  The outer peripheral edge of the inner peripheral portion 6 is placed on the inward protruding portion 75 of the outer peripheral portion 7, and the heat radiation fins 61 of the inner peripheral portion 6 pass through the central hole of the outer peripheral portion 7. In a state of being arranged so as to project downward, the periphery of the contact area between the outer peripheral edge of the inner peripheral portion 6 and the inner peripheral edge of the outer peripheral portion 7 is brazed, welded, adhesive coated, etc. Be combined. As a result, the inner peripheral portion 6 and the outer peripheral portion 7 are joined and integrated (connected and integrated) to form the base plate 5.

  Here, in the present embodiment, the inner peripheral portion 6 of the base plate 5 is made of a material having a higher thermal conductivity than the outer peripheral portion 7. Further, the outer peripheral portion 7 is made of a material having higher strength than the inner peripheral portion 6.

  Specifically, as the material of the inner peripheral portion 6, it is preferable to use pure aluminum having an alloy number of A1050 (thermal conductivity 230 W / mK, proof stress 30 MPa), A1100 (thermal conductivity 220 W / mK, proof stress 35 MPa). it can. As the material of the outer peripheral portion 7, an Al-Mg-Si alloy such as alloy No. A6063 (thermal conductivity 210 W / mK, proof stress 145 MPa), Al-Mg-Si alloy such as A3003 (thermal conductivity 170 W / mK, proof stress 125 MPa). A Mn-based alloy can be preferably used.

  The base plate 5 having the above configuration is assembled to the container body 1 to form a cooler. That is, the heat radiation fins 61 of the base plate 5 are accommodated in the container body 1 through the upper surface opening 11 of the container body 1, and the lower surface of the outer peripheral portion 7 of the base plate 5 is attached to the peripheral edge of the upper surface opening of the container body 1 by an O-ring. It is placed via a seal member 3 such as a metal gasket or a metal gasket. In this state, the bolt 4 penetrating the outer peripheral portion 7 from the upper side is fastened and fixed to the peripheral edge portion of the upper opening of the container body 1. As a result, the base plate 5 is assembled to the container body 1. In this assembled state, a refrigerant flow path sealed by the container body 1 and the base plate 5 is formed, and the heat radiation fins 6 are arranged in the refrigerant flow path.

  In this assembled state, the lower end of the heat dissipation fin 61 is preferably in contact with the inner bottom surface of the container body 1.

  The mounting substrate 2 provided on the upper side of the base plate 5 is provided with an insulating plate 21, and wiring layers 22 and 22 made of aluminum are laminated on the upper and lower surfaces of the insulating plate 21, and the upper surface of the upper wiring layer 22. A power semiconductor element 24 is fixed to the semiconductor device via a solder layer 23.

  The wiring layer 22 on the lower side of the mounting substrate 2 is joined to the upper surface of the inner peripheral portion 6 of the base plate 5 by brazing, welding, adhesive coating, or the like. As a result, the semiconductor device of this embodiment is formed.

  In the semiconductor device of the present embodiment having the above-described configuration, the container body 1 is provided with a refrigerant inlet and a refrigerant outlet (not shown), and the refrigerant flows into the container body 1 (refrigerant flow path) via the refrigerant inlet. After flowing through each of the plurality of heat radiation fins 61 in the refrigerant flow path, the refrigerant flows out from the refrigerant outlet. In this way, heat exchange between the refrigerant flowing through the container body 1 (refrigerant flow path) and the semiconductor element 24 causes heat generated from the semiconductor element 24 to be released to the outside via the refrigerant, and The element 24 is adapted to be cooled.

  According to the semiconductor device of this embodiment having the above-described configuration, the inner peripheral portion 6 of the base plate 5 on which the heat radiation fins 61 are formed and the outer peripheral portion 7 fixed to the container body 1 are formed separately. The peripheral portion 6 is made of a material having high thermal conductivity, and the outer peripheral portion 7 is made of a material having high strength. Therefore, the heat generated from the semiconductor element 24 is smoothly absorbed by the refrigerant in the container body 1 via the inner peripheral portion 6, heat can be efficiently exchanged, and sufficient cooling performance can be obtained. Further, the outer peripheral portion 7 is not deformed by the elastic repulsive force of the seal member 3, and the outer peripheral portion 7 can be securely attached to the container body 1 in a state where the seal member 3 is compressed. Therefore, the outer peripheral portion 7 serving as the base plate 5 can be attached to the container body 1 in a stable state with high positional accuracy while sufficiently ensuring the hermeticity, and the product value can be remarkably improved.

  Further, in the present embodiment, since the plate thickness of the inner peripheral portion 6 of the base plate 5 is made smaller than the plate thickness of the outer peripheral portion 7, the heat transfer coefficient of the inner peripheral portion 6 can be further improved and cooling can be performed. The performance can be further improved, the strength of the outer peripheral portion 7 can be further improved, and the base plate 5 can be attached to the container body 1 in a more stable state.

  Further, in the present embodiment, the inward protruding portion 75 is formed on the inner peripheral edge of the outer peripheral portion 7, and the outer peripheral edge of the inner peripheral portion 6 is arranged on the inward protruding portion 75. The seal member 3 can be arranged at the position of the lower surface of the inward protruding portion 75. Therefore, in the first embodiment, the seal member 3 can be arranged closer to the upper surface opening 11 of the container body 1 than in the semiconductor device of the second embodiment described later shown in FIGS. 3 and 4. . That is, in the first embodiment, the seal member 3 can be arranged at a position closer to the inner side, and the outer diameter dimension of the outer peripheral portion 7 serving as the base plate 5 can be reduced by that amount, which in turn reduces the size and weight of the entire semiconductor device. Can be achieved.

<Second Embodiment>
3 is a cross-sectional view showing a power semiconductor device to which a cooler according to a second embodiment of the present invention is applied, and FIG. 4 is a cross-sectional view showing enlarged main parts of the semiconductor device. This corresponds to an enlarged cross-sectional view of a portion surrounded by a chain line.

  As shown in both figures, in this semiconductor device, a concave step portion 76 that opens inward and downward is formed below the inner peripheral edge of the outer peripheral portion 7 of the base plate 5. Then, in a state where the outer peripheral edge of the inner peripheral portion 6 is fitted in the concave stepped portion 76 of the outer peripheral portion 7, the periphery of the contact area between the inner peripheral portion 6 and the outer peripheral portion 7 is brazed and welded. The base plate 5 is formed by being bonded by a treatment, an adhesive coating treatment, or the like. Further, the base plate 5 is attached to the container body 1 in the same manner as in the first embodiment, and the mounting substrate 2 is mounted on the base plate 5 to form the semiconductor device of the second embodiment.

  Since the other configurations of the semiconductor device of the second embodiment are substantially the same as those of the first embodiment, the same or corresponding parts will be denoted by the same reference symbols and redundant description will be omitted.

  Also in the semiconductor device of the second embodiment, similar to the above, sufficient cooling performance can be obtained, and the outer peripheral portion 7 as the base plate 5 can be attached to the container body 1 in a stable state with high positional accuracy.

  Moreover, in the semiconductor device of the second embodiment, a concave step portion 76 is formed below the inner peripheral edge of the outer peripheral portion 7 of the base plate 5, and the inner peripheral portion 6 is formed in the concave step portion 76. Since the outer peripheral edge is accommodated, it is easy to arrange the lower surface of the inner peripheral portion 6 and the lower surface of the outer peripheral portion 7 in the same plane (flush). Therefore, there is no step between the lower surface of the inner peripheral portion 6 and the lower surface of the outer peripheral portion 7, and the refrigerant R along the lower surface of the base plate 5 flows from the outer peripheral portion 7 to the inner peripheral portion 6 as shown by the arrow mark in FIG. And smoothly flows from the inner peripheral portion 6 to the outer peripheral portion 7. In this way, the flow of the refrigerant R in the refrigerant channel becomes smoother, and the cooling performance can be further improved.

<Modification>
In the above-described embodiment, the inward protruding portion 75 and the concave stepped portion 76 are formed on the inner peripheral edge of the outer peripheral portion 7 of the base plate 5, and the outer peripheral edge of the inner peripheral portion 6 is formed on the inner peripheral edge of the outer peripheral portion 7. Are arranged so that they can be engaged in the axial direction, but the invention is not limited thereto, and in the present invention, the shape of the joint between the outer peripheral portion and the inner peripheral portion may be any shape. For example, the outer peripheral edge (outer peripheral end surface) of the inner peripheral portion 6 and the inner peripheral end edge (inner peripheral end surface) of the outer peripheral portion 7 may be formed as vertical surfaces, respectively. Alternatively, the outward protruding portion or the concave step portion may be formed.

  Further, in the above-described embodiment, the cooler for cooling the semiconductor element 24 has been described as an example, but the present invention is not limited thereto, and the present invention can be applied to a cooler for cooling a heating element other than the semiconductor element. it can.

  Further, in the above embodiment, the case where the base plate is fixed to the container body by the bolts has been described as an example, but the present invention is not limited thereto, and in the present invention, the fixing means for the base plate to the container body is not limited. Absent. For example, instead of bolts, fixing means such as screws or clamps may be used for fixing.

  The cooler of the present invention can be suitably used as a cooling device for cooling a heating element such as a power semiconductor element.

1: container body 11: upper surface opening 24: semiconductor element 3: seal member 5: base plate 6: inner peripheral portion 61: heat dissipation fin 7: outer peripheral portion 75: inward projecting portion 76: concave step portion

Claims (10)

The heat dissipation device includes a box-shaped container body having an opening on the upper surface, a base plate on which a large number of heat radiation fins are formed on the lower surface side of the inner peripheral portion, and a heating element can be arranged on the upper surface side of the inner peripheral portion. With the fins accommodated in the container body through the upper surface opening thereof, the outer peripheral portion of the base plate is fixed to the upper surface opening peripheral portion of the container body through a seal member, whereby the base plate is formed. A cooler which is assembled to the container body so as to close its upper opening,
The inner peripheral portion and the outer peripheral portion of the base plate are formed as separate bodies, and the inner peripheral portion and the outer peripheral portion of the separate body are connected and integrated. Cooler.   The cooler according to claim 1, wherein the outer peripheral portion of the base plate is formed of a material having higher strength than the inner peripheral portion.   The cooler according to claim 1 or 2, wherein the inner peripheral portion of the base plate is formed of a material having a higher thermal conductivity than the outer peripheral portion.   The cooler according to claim 1, wherein a plate thickness of an outer peripheral portion of the base plate is formed to be thicker than a plate thickness of the inner peripheral portion.   The cooler according to any one of claims 1 to 4, wherein a lower surface of the outer peripheral portion of the base plate and a lower surface of the inner peripheral portion are arranged in substantially the same plane. A recessed step portion is provided on the lower side of the inner peripheral edge of the outer peripheral portion of the base plate,
The cooler according to claim 1, wherein the cooler is arranged such that the outer peripheral edge of the inner peripheral portion is accommodated in the recessed step portion. An inward protruding portion that protrudes inward is provided below the inner peripheral edge of the outer peripheral portion of the base plate,
The cooler according to claim 1, wherein the outer peripheral edge of the inner peripheral portion is arranged in a state of being placed on the content protruding portion.   The cooler according to claim 1, wherein the outer peripheral portion and the inner peripheral portion of the base plate are made of aluminum. A box-shaped container body having an opening on the upper surface, a base plate of a cooler assembled so as to close the upper opening,
On the lower surface side, a large number of fins that can be accommodated in the container body through the upper surface opening are formed, and on the upper surface side, an inner peripheral portion in which a heating element can be arranged,
An outer peripheral portion, which is provided outside the inner peripheral portion and can be fixed to a top opening edge portion of the container body via a seal member,
The inner peripheral portion and the outer peripheral portion are formed as separate bodies, and the inner peripheral portion and the outer peripheral portion of the separate body are connected and integrated to form a base for a cooler. Board. A box-shaped container body having an opening on the upper surface; a base plate having a large number of heat radiation fins formed on the lower surface side of the inner peripheral portion; and a semiconductor element arranged on the upper surface of the inner peripheral portion of the base plate, By fixing the outer peripheral portion of the base plate to the peripheral edge portion of the upper surface opening of the container main body via a seal member in a state where the heat radiation fin is accommodated in the container main body through the upper surface opening, A semiconductor device in which a base plate is assembled to the container body so as to close an upper surface opening thereof,
The inner peripheral portion and the outer peripheral portion of the base plate are formed as separate bodies, and the inner peripheral portion and the outer peripheral portion of the separate body are connected and integrated. Semiconductor device.

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