JP2015035501A - Heat radiation module and semiconductor module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress occurrence of cracking on a ceramics substrate and occurrence of peeling at a junction portion between the ceramics substrate and metal plate, in a heat radiation module.SOLUTION: A heat radiation module includes a ceramics substrate containing a first surface positioned at one end in thickness direction and a second surface positioned at the other end, a first metal layer containing a first contact surface contacting to the first surface, and a second metal layer which contacts to the second surface, with a heat radiation fin being formed. A first outer peripheral end which is an outer peripheral end of the first contact surface is disposed, with a second outer peripheral end that is an outer peripheral end of the second contact surface as a reference, at a position 1.5 mm or less inside and 1.5 mm or less outside. The second outer peripheral end is positioned inside a third outer peripheral end which is an outer peripheral end of the ceramics substrate.

Description

  The present invention relates to a heat dissipation module and a semiconductor module using the heat dissipation module.

  In a semiconductor module having an electronic component such as a semiconductor element or a capacitor, a heat dissipation module may be used to release heat of the electronic component. As such a heat dissipation module, a heat dissipation module in which a metal plate on which a large number of fine fins (fins) are formed and a ceramic substrate is integrated has been proposed (Patent Document 1). In the heat dissipation module described in Patent Document 1, a large heat dissipation area can be secured by a large number of fins, and the heat dissipation module can be downsized.

JP 2011-230954 A

  In recent years, the usage environment of semiconductor modules has become very high. For example, so-called semiconductor modules (so-called power modules) used for power control in electric vehicles are used in a very high temperature environment of 200 degrees Celsius or higher. However, in the heat dissipation module described in Patent Document 1, each fin is deformed in a high temperature environment, and the entire metal plate on which the fin is formed may be deformed due to the deformation. When the entire metal plate is deformed in this way, stress is applied to the ceramic substrate due to the difference in the coefficient of thermal expansion between the metal plate and the ceramic substrate, and the occurrence of cracks (cracks) in the ceramic substrate, There was a problem that peeling of the joint portion occurred between the two.

  The present invention has been made to solve the above-described problems, and can be realized as the following forms or application examples.

  (1) According to one aspect of the present invention, a ceramic substrate having a first surface located at one end in the thickness direction and a second surface located at the other end in the thickness direction, and the first surface There is provided a heat dissipation module comprising: a first metal layer having a first contact surface that is in contact; and a second metal layer in contact with the second surface and having a heat dissipation fin formed thereon. In this heat dissipation module, the first outer peripheral end, which is the outer peripheral end of the first contact surface, is 1.5 mm or less on the inner side and the outer side with respect to the second outer peripheral end, which is the outer peripheral end of the second contact surface. The second outer peripheral end is disposed at a position of 1.5 mm or less, and the second outer peripheral end is positioned inside a third outer peripheral end which is an outer peripheral end of the ceramic substrate. According to the heat dissipation module of this embodiment, the first outer peripheral end is arranged at a position of 1.5 mm or less on the inner side and 1.5 mm or less on the outer side with respect to the second outer peripheral end. Occurrence of occurrence, peeling of the bonded portion between the first metal layer and the ceramic substrate, and peeling of the bonded portion of the second metal layer and the ceramic substrate can be suppressed. Due to the difference in thermal expansion coefficient between the ceramic substrate and the first metal layer and the difference in thermal expansion coefficient between the ceramic substrate and the second metal layer, if the use environment temperature of the heat dissipation module changes, the ceramics Stress is applied to the substrate from the first metal layer side and the second metal layer side. However, since the first outer peripheral end is arranged at a position of 1.5 mm or less on the inner side and 1.5 mm or less on the outer side with respect to the second outer peripheral end, the stress applied from the two metal layer sides is not affected. By canceling, deformation (warping) of the ceramic substrate can be suppressed. For this reason, generation | occurrence | production of the crack in a ceramic substrate, the generation | occurrence | production of the joining part of a 1st metal layer and a ceramic substrate, and the generation | occurrence | production of the peeling of the joining part of a 2nd metal layer and a ceramic substrate can be suppressed. In addition, since the second outer peripheral edge is located on the inner side of the third outer peripheral edge, which is the outer peripheral edge of the ceramic substrate, the occurrence of cracks and the occurrence of peeling of the joint portion between the second metal layer and the ceramic substrate are suppressed. it can. Due to the difference in thermal expansion coefficient between the ceramic substrate and the second metal layer, when the use environment temperature of the heat dissipation module changes, stress is applied to the ceramic substrate from the second metal layer side. In particular, since the fin is greatly deformed with temperature change, the stress applied to the ceramic substrate is large. Here, if the position of the second outer peripheral edge of the second metal layer is outside or coincides with the position of the third outer peripheral edge of the ceramic substrate, a crack is generated in the vicinity of the outer peripheral edge of the ceramic substrate having relatively low rigidity. Or peeling of the bonded portion between the ceramic substrate and the second metal layer may occur. However, according to the heat dissipation module of this embodiment, the second outer peripheral edge is located inside the third outer peripheral edge, which is the outer peripheral edge of the ceramic substrate, so that the second metal layer does not exist in the vicinity of the outer peripheral edge of the ceramic substrate. You can For this reason, generation | occurrence | production of the crack in the outer periphery end vicinity of a ceramic substrate and peeling of the joining part of a ceramic substrate and a 2nd metal layer can be suppressed.

  (2) In the heat dissipation module of the above aspect, the first metal layer includes a first outer peripheral end surface including the first outer peripheral end and parallel to the thickness direction, and the second metal layer includes the second outer peripheral surface. A second outer peripheral end surface including the outer peripheral end and parallel to the thickness direction, wherein the third outer peripheral end of the ceramic substrate is a third outer peripheral end surface parallel to the thickness direction; In a predetermined direction perpendicular to any of the first outer peripheral end surface, the second outer peripheral end surface, and the third outer peripheral end surface, the position of the first outer peripheral end surface is determined based on the position of the second outer peripheral end surface. Along the direction of 1.5 mm or less on the inside and 1.5 mm or less on the outside along the predetermined direction. In the predetermined direction, the position of the second outer peripheral end surface is the third position. It may be inside the position of the outer peripheral end face. According to the heat dissipation module of this aspect, the first metal layer has the first outer peripheral end surface, the second metal layer has the second outer peripheral end surface, and the ceramic substrate has the third outer peripheral end surface. Generation | occurrence | production of the generation | occurrence | production of a crack, the peeling of the junction part of a 1st metal layer and a ceramic substrate, and the generation | occurrence | production of peeling of the junction part of a 2nd metal layer and a ceramic substrate can be suppressed.

  (3) In the heat dissipation module of the above aspect, the fin may be formed by cutting and raising the base material of the second metal layer. According to the heat dissipation module of this embodiment, fins having a small thickness and a small pitch can be formed, and the heat dissipation performance of the heat dissipation module can be improved.

  (4) In the heat dissipation module of the above aspect, the plurality of fins are formed in the second metal layer, and the length in the thickness direction of each fin is 3 mm or more and 7 mm or less, The pitch between adjacent fins may be 0.2 mm or more and 1.0 mm or less, and the thickness of each fin may be 0.1 mm or more and 0.5 mm or less. According to this form of the heat dissipation module, the heat dissipation performance of the heat dissipation module can be improved.

  (5) In the heat dissipation module of the above aspect, the second metal layer includes the fin and a joint portion joined to the fin and the second surface, and the thickness direction of the joint portion is in the thickness direction. The length may be not less than 0.5 millimeters and not more than 1.5 millimeters. According to the heat dissipation module of this embodiment, since the length in the thickness direction of the joint is 0.5 mm or more, it is easy to manufacture the joint. In addition, since the length of the joining portion in the thickness direction is 1.5 millimeters or less, it is possible to prevent the second metal layer from becoming very thick. For this reason, a thermal radiation module can be reduced in size.

  (6) According to the other form of this invention, a semiconductor module provided with the thermal radiation module of the said form is provided. In this semiconductor module, a semiconductor element is bonded to the first metal layer, and the semiconductor element, the first metal layer, and the ceramic substrate are covered with a resin. According to the semiconductor module of this aspect, since the semiconductor element, the first metal layer, the ceramic substrate, and the resin can be sealed, the semiconductor element and the heat dissipation module (the first metal layer and the ceramic substrate) are damaged by external stress. This can be suppressed.

  (7) According to the other form of this invention, a semiconductor module provided with the thermal radiation module of the said form is provided. In the semiconductor module, a semiconductor element is bonded to the first metal layer, and a case is provided that covers the semiconductor element and the heat dissipation module. According to the semiconductor module of this embodiment, the semiconductor element and the heat dissipation module can be prevented from being damaged by external stress.

  The present invention can also be realized in various forms other than the heat dissipation module and the semiconductor module. For example, it can be realized in the form of an electric vehicle, a train, and a machine tool on which a semiconductor module is mounted, a method for manufacturing a heat dissipation module, a method for manufacturing a semiconductor module, and the like.

It is sectional drawing which shows the structure of the semiconductor module as one Embodiment of this invention. It is explanatory drawing which shows the detailed structure of the thermal radiation module 10 shown in FIG. 4 is a flowchart showing a procedure of a method for manufacturing the heat dissipation module 10. It is explanatory drawing which shows the evaluation result of the temperature change tolerance of each sample s1-s10. It is explanatory drawing which shows the detailed structure of sample s1 of 1st Example. It is explanatory drawing which shows the detailed structure of sample s4 of 4th Example. It is explanatory drawing which shows the detailed structure of sample s9 of a 3rd comparative example. It is sectional drawing which shows the detailed structure of the thermal radiation module of the 1st aspect in a modification. It is sectional drawing which shows the detailed structure of the thermal radiation module of the 2nd aspect in a modification. It is sectional drawing which shows the structure of the semiconductor module 100a in a modification. It is a top view which shows the structure of the thermal radiation module of the 3rd thru | or 5th aspect in a modification.

A. First embodiment:
A1. Device configuration:
FIG. 1 is a cross-sectional view showing a configuration of a semiconductor module as an embodiment of the present invention. The semiconductor module 100 includes a heat dissipation module 10 as an embodiment of the present invention, a semiconductor element 50, a first case 110, a second case 112, a lid 113, an external terminal 111, and a wiring 114. Yes. In the present embodiment, the semiconductor module 100 is a so-called power module, and is used for power control in an electric vehicle, a train, a machine tool, and the like.

  The heat dissipation module 10 releases the heat of the semiconductor element 50 to the outside. The detailed configuration of the heat dissipation module 10 will be described later. The semiconductor element 50 is a power semiconductor element (power device). As the semiconductor element 50, for example, a power MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), a diode (such as a Schottky barrier diode), or the like may be employed. The semiconductor element 50 is joined to the heat dissipation module 10. In FIG. 1, the semiconductor module 100 includes one semiconductor element 50, but may include a plurality of semiconductor elements 50. Further, in addition to the semiconductor element 50, an arbitrary electronic component such as a capacitor or a resistor may be provided.

  The first case 110 accommodates a part of the heat radiation module 10 (a part excluding fins described later), the semiconductor element 50, and the wiring 114. The second case 112 accommodates a part of the heat dissipation module 10 (fins described later). The first case 110 and the second case 112 are joined to each other. The lid 113 seals the first case 110. A space surrounded by the lid 113 and the first case 110 (a space excluding the heat dissipation module 10, the semiconductor element 50, and the wiring 114) is filled with a resin (mold resin) 115.

  A part of the external terminal 111 is exposed from the first case 110 and the lid 113, and the other part (except for a tip part of a protruding part 109 described later) is disposed inside the first case 110. A portion of the external terminal 111 exposed from the first case 110 and the lid 113 is connected to a wiring (not shown). The external terminal 111 includes a protruding portion 109. The protruding portion 109 protrudes from the inside of the first case 110 toward a region surrounded by the first case 110 and the lid 113 (a space filled with the resin 115). The protruding portion 109 is formed of a conductive material like the other portions of the external terminal 111. The protruding portion 109 is connected to the semiconductor element 50 and the heat dissipation module 10 by wire bonding, respectively. Specifically, the protruding portion 109 is electrically connected to the semiconductor element 50 and the heat dissipation module 10 (first metal layer 11 to be described later) via a wiring 114 that is a thin metal wire.

  FIG. 2 is an explanatory diagram showing a detailed configuration of the heat dissipation module 10 shown in FIG. In FIG. 2, the uppermost stage shows a plan view of the heat dissipation module 10. In FIG. 2, the middle part shows a cross-sectional view of the heat dissipation module 10, and the bottom part shows a bottom view of the heat dissipation module 10.

  As shown in the middle part of FIG. 2, the heat dissipation module 10 includes a ceramic substrate 12, a first metal layer 11, and a second metal layer 13, and the ceramic substrate 12, the first metal layer 11, and the second metal. The layer 13 has a stacked structure.

The ceramic substrate 12 is configured by a thin plate member formed of a ceramic material. As the ceramic material, for example, insulating ceramics such as silicon nitride (Si ₃ N ₄ ), aluminum nitride (AlN), alumina oxide (Al ₂ O ₃ ), aluminum nitride (AlN) may be employed. . As shown in the middle part of FIG. 2, the thickness direction of the ceramic substrate 12 coincides with the Z-axis direction. In the present embodiment, the Z-axis direction is a general term for the + Z direction and the −Z direction. Similarly, the X-axis direction is a generic term for the + X direction and the -X direction, and the Y-axis direction is a generic term for the + Y direction and the -Y direction. The ceramic substrate 12 includes a first surface S1 located at one end in the thickness direction and a second surface S2 located at the other end in the thickness direction.

  The 1st metal layer 11 is comprised by the thin plate-shaped member formed with the metal. The first metal layer 11 functions as a circuit layer for mounting the semiconductor element 50. Examples of the metal constituting the first metal layer 11 include a metal having high thermal conductivity such as aluminum (Al) and copper (Cu), and a metal having low thermal expansion such as tungsten (W) and molybdenum (Mo). Alternatively, a composite material such as copper-tungsten (Cu-W) or copper-molybdenum (Cu-Mo) may be used. The first metal layer 11 is bonded to the first surface S1 of the ceramic substrate 12. Note that the surface of the first metal layer 11 opposite to the surface bonded to the first surface S1 is bonded to the semiconductor element 50 as shown in FIG. The joining of the first metal layer 11 and the semiconductor element 50 may be realized by soldering, for example. As shown in the middle of FIG. 2, the thickness direction of the first metal layer 11 coincides with the Z-axis direction. As shown in the uppermost stage of FIG. 2, the planar view shape of the first metal layer 11 is a rectangle. The longitudinal direction in the plan view shape of the first metal layer 11 is parallel to the X-axis direction. Moreover, the short side direction in the planar view shape of the first metal layer 11 is parallel to the Y-axis direction.

  The second metal layer 13 is made of metal and includes a joint portion 14 and a large number of fins 15. As the metal, the same metal as the first metal layer 11 may be adopted. In addition, the 1st metal layer 11 and the 2nd metal layer 13 may be formed with the same kind of metal, and may be formed with a mutually different kind of metal. In FIG. 1 and FIG. 2, the second metal layer 13 includes seven fins 15, but may include any number of fins 15. As shown in the lowermost stage of FIG. 2, the bottom metal shape of the second metal layer 13 is rectangular. The longitudinal direction in the bottom view shape of the second metal layer 13 is parallel to the X-axis direction. The short direction in the bottom view shape of the second metal layer 13 is parallel to the Y-axis direction.

  One end of the joining portion 14 in the thickness direction is formed in a planar shape and joined to the second surface S2 of the ceramic substrate 12. A large number of fins 15 are formed on the opposite side of the bonding portion 14 from the surface bonded to the second surface S2. As will be described later, the fin 15 is formed by cutting and raising with a blade. For this reason, in FIG. 2, the appearance shape of the joint portion 14 is shown in a thin plate shape, but actually, it has a complicated shape due to processing marks when the fins 15 are formed.

  The fin 15 has a curved thin plate-like appearance having a constant cross-sectional shape (cross-sectional shape parallel to the XZ plane) at an arbitrary position in the Y-axis direction. As shown in the middle part of FIG. 2, the cross-sectional shape of the fin 15 is a curved shape in an arc shape. In the present embodiment, the length of the fin 15 in the Z-axis direction (in other words, the length of the ceramic substrate 12 in the thickness direction) h1 is not less than 3 millimeters and not more than 7 millimeters. Moreover, the pitch p1 between the fins 15 adjacent along the X-axis direction is not less than 0.2 millimeters and not more than 1.0 millimeters. The thickness t1 of the fin 15 is not less than 0.1 millimeter and not more than 0.5 millimeter.

  As shown in the middle and lowermost stages of FIG. 2, the outer peripheral edge of the second metal layer 13 is located inside the outer peripheral edge of the ceramic substrate 12. For example, the outer peripheral end surface 13 a that is one of the outer peripheral ends of the second metal layer 13 is positioned inside the outer peripheral end surface 12 a that is one of the outer peripheral ends of the ceramic substrate 12. Here, “inner side” in the present embodiment means a side closer to the center of the second metal layer 13 and the center of the ceramic substrate 12 in the direction along the XY plane (direction perpendicular to the Z axis). In addition, the “outside” in the present embodiment means a side closer to the outer peripheral end of the second metal layer 13 and the outer peripheral end of the ceramic substrate 12 in the direction along the XY plane (direction perpendicular to the Z axis). Therefore, when the outer peripheral end face 12a of the ceramic substrate 12 is used as a reference (origin), and the −X direction and the + X direction are respectively defined as plus and minus, the position of the outer circumference end face 13a of the second metal layer 13 is minus. Yes (less than 0).

  In the present embodiment, as described above, the outer peripheral end (outer peripheral end surface 13a) of the second metal layer 13 is positioned on the inner side of the outer peripheral end (outer peripheral end surface 12a) of the ceramic substrate 12, thereby causing cracks in the ceramic substrate 12 to occur. Generation | occurrence | production and peeling of the junction part of the 2nd metal layer 13 and the ceramic substrate 12 are suppressed. In other words, when the outer peripheral end surface 12a of the ceramic substrate 12 is used as a reference (origin) and the −X direction and the + X direction are respectively defined as plus and minus, the position of the outer circumference end surface 13a of the second metal layer 13 is plus. By making it larger (greater than 0), the generation of cracks in the ceramic substrate 12 and the separation of the joint portion between the second metal layer 13 and the ceramic substrate 12 are suppressed. Generation | occurrence | production of this crack and suppression of peeling are demonstrated in detail. Due to the difference in thermal expansion coefficient between the ceramic substrate 12 and the second metal layer 13 when the use environment temperature of the heat dissipation module 10 (semiconductor module 100) is changed, the second metal is compared with the ceramic substrate 12. Layer 13 shrinks or extends more. For this reason, stress is applied to the ceramic substrate 12. In particular, since the fin 15 has a small thickness, deformation due to a temperature change is large. Therefore, in the configuration including a large number of fins 15 as in the present embodiment, the stress applied to the ceramic substrate 12 is large. Here, the position along the X-axis direction of the outer peripheral end (outer peripheral end surface 13a) of the second metal layer 13 coincides with the position along the X-axis direction of the outer peripheral end (outer peripheral end surface 12a) of the ceramic substrate 12. Or, the position along the X-axis direction of the outer peripheral end (outer peripheral end surface 13a) of the second metal layer 13 is outside the position along the X-axis direction of the outer peripheral end (outer peripheral end surface 12a) of the ceramic substrate 12. If it is positioned, cracks may occur near the outer peripheral edge of the ceramic substrate 12 with relatively low rigidity, or separation of the bonded portion between the ceramic substrate 12 and the second metal layer 13 may occur. Therefore, in this embodiment, the second metal layer 13 is thermally deformed by positioning the outer peripheral end (outer peripheral end surface 13a) of the second metal layer 13 on the inner side of the outer peripheral end (outer peripheral end surface 12a) of the ceramic substrate 12. Accompanying cracks in the ceramic substrate 12 and peeling of the bonded portion between the ceramic substrate 12 and the second metal layer 13 are suppressed.

  In the present embodiment, when the outer peripheral end face 13a of the second metal layer 13 is used as a reference (origin) and the −X direction and the + X direction are defined as plus and minus, respectively, the outer peripheral end face 11a of the first metal layer 11 The position d2 along the X-axis direction is set to −1.5 millimeters or more and +1.5 millimeters or less. In other words, the position d2 of the outer peripheral end surface 11a of the first metal layer 11 is set to a position of 1.5 mm or less on the inner side and 1.5 mm or less on the outer side with respect to the outer peripheral end surface 13a of the second metal layer 13. .

  Thus, in this embodiment, the position d2 of the outer peripheral end surface 11a of the first metal layer 11 is set to 1.5 mm or less on the inner side and 1.5 mm on the outer side with respect to the outer peripheral end surface 13a of the second metal layer 13. By setting it to millimeters or less, generation of cracks in the ceramic substrate 12, occurrence of separation at the joint portion between the first metal layer 11 and the ceramic substrate 12, and separation of the joint portion between the second metal layer 13 and the ceramic substrate 12 are caused. The generation is suppressed. Generation | occurrence | production of this crack and suppression of peeling are demonstrated in detail. As described above, when the use environment temperature of the heat dissipation module 10 (semiconductor module 100) changes due to the difference in thermal expansion coefficient between the ceramic substrate 12 and the second metal layer 13, the ceramic substrate 12 In comparison, the second metal layer 13 tends to shrink or extend more, so that stress is applied to the ceramic substrate 12. Similarly, stress is applied to the ceramic substrate 12 due to the difference in coefficient of thermal expansion between the ceramic substrate 12 and the first metal layer 11. Thus, stress is applied to the ceramic substrate 12 on the first surface S1 and the second surface S2, respectively. Since the directions of these stresses are symmetrical in the Z-axis direction with the ceramic substrate 12 interposed therebetween, when these stresses are approximately equal, they are canceled from each other, and deformation (warping) of the ceramic substrate 12 is suppressed. Therefore, in this embodiment, the position d2 of the outer peripheral end surface 11a of the first metal layer 11 is set to 1.5 mm or less on the inner side and 1.5 mm or less on the outer side with respect to the outer peripheral end surface 13a of the second metal layer 13. By doing so, the stress applied to each of the first surface S1 and the second surface S2 is made substantially equal to suppress deformation (warpage) of the ceramic substrate 12. Thereby, generation | occurrence | production of the crack in the ceramic substrate 12, generation | occurrence | production of peeling of the junction part of the 1st metal layer 11 and the ceramic substrate 12, and generation | occurrence | production of peeling of the junction part of the 2nd metal layer 13 and the ceramic substrate 12 are suppressed. I am doing so.

  The outer peripheral end face 11a described above corresponds to the first outer peripheral end face in the claims. The outer peripheral end face 12a is the second outer peripheral end face in the claims, the outer peripheral end face 13a is the third outer peripheral end face in the claims, the X-axis direction is the predetermined direction in the claims, and the ceramic substrate 12 in the first metal layer 11 is The contact surface (the end surface in the −Z direction) is the first contact surface in the claims, and the surface in the second metal layer 13 that contacts the ceramic substrate 12 (the end surface in the + Z direction) is the second contact surface in the claims. The outer peripheral edge of the surface of the first metal layer 11 that contacts the ceramic substrate 12 (the end surface in the −Z direction) is the first outer peripheral end of the claims, and the second metal layer 13 is the surface that contacts the ceramic substrate 12 (the end surface in the + Z direction). ) Corresponds to the second outer peripheral end of the claims, and the outer peripheral end surface 12a of the ceramic substrate 12 corresponds to the third outer peripheral end of the claims.

A2. Manufacturing heat dissipation module:
FIG. 3 is a flowchart showing the procedure of the method for manufacturing the heat dissipation module 10. In addition, in FIG. 3, the process result of each process is typically shown on the right side of each process. First, the ceramic substrate 22 and the two metal plates 21 and 23 which are the base materials of the two metal layers 11 and 13 are prepared (step S105). The ceramic substrate 22 can be manufactured by a known method. That is, a slurry containing a ceramic material and an organic binder is formed into a sheet shape by casting using a doctor blade method or the like, and the sheet is punched out with a fixed die, thereby forming a green ceramic sheet (green sheet). And the ceramic substrate 22 can be manufactured by baking after baking this ceramic raw sheet, degreasing | defatting. The method for manufacturing the ceramic substrate 22 is not limited to the method using the doctor blade method described above. For example, a method in which a press fired body is cut into a predetermined shape and polished may be employed. As shown in FIG. 3, the length of the metal plate 23 that is the base material of the second metal layer 13 is previously shorter than the length of the ceramic substrate 22 in the X-axis direction. Is formed. On the other hand, the length in the X-axis direction of the metal plate 21 that is the base material of the first metal layer 11 is the same as the length in the X-axis direction of the ceramic substrate 22.

  The metal plate 21 and the ceramic substrate 22 are joined, and the metal plate 23 and the ceramic substrate 22 are joined (step S110). In the present embodiment, the joining in step S110 is realized by brazing. Specifically, first, a brazing material is disposed between the metal plate 21 and the ceramic substrate 22 and between the metal plate 23 and the ceramic substrate 22, and these base materials (metal plate 21, ceramic substrate) are arranged. 22, metal plate 23 and brazing material) are laminated. As the brazing material, a foil-like brazing material or a paste-like brazing material can be employed. Next, the obtained laminate is sandwiched in the laminating direction using a jig and heated for a predetermined time while being pressed, and between the metal plate 21 and the ceramic substrate 22 and between the metal plate 23 and the ceramic substrate 22. Join between. Instead of brazing, any joining method such as molten metal joining may be used for joining between the metal plate 21 and the ceramic substrate 22 and between the metal plate 23 and the ceramic substrate 22. In addition, the ceramic substrate 12 (ceramic layer) is formed by this process (step S110).

  Next, in the metal plate 21 serving as the base material of the first metal layer 11, the peripheral portion is etched and a circuit pattern is formed (step S115). In this embodiment, chemical etching is employed as a method for etching the peripheral portion. Instead of chemical etching, any method such as milling or laser etching may be employed. As a method for forming a circuit pattern, this embodiment employs a method in which chemical etching is performed after a resist film is attached to the metal plate 21 so as to have a predetermined circuit shape. Instead of the above-described chemical etching method, a method of brazing a plurality of metal plates formed in a circuit shape by milling or press punching may be employed.

  Next, the fin 15 is formed in the metal plate 23 (step S120). In the present embodiment, the fins 15 are formed by cutting and raising. Specifically, as shown in FIG. 3, a blade 60 (cutting blade of a cutting tool (not shown)) is obliquely cut into the metal plate 23 to form a large number of arc-shaped fins 15. On the surface of the fin 15 formed by the cutting and raising process, a processing trace at the time of the cutting and raising extending in the Z-axis direction may be generated. In addition, the outer peripheral surface of the fin 15 that contacts the blade 60 during processing tends to have higher gloss than the inner peripheral surface that does not contact the blade 60. Note that the fins 15 may be formed by an arbitrary method such as groove cutting using a cutting blade instead of the cutting and raising process. The heat dissipation module 10 is completed through the above steps.

B. Example:
Based on the embodiment described above, six heat dissipation modules 10 (sample s1 of the first example, sample s2 of the second example, sample s3 of the third example, sample s4 of the fourth example, and fifth example) S5 and the sample s6) of the sixth embodiment were manufactured. Further, based on a form different from the above-described embodiment, four heat radiation modules (first comparative example sample s7, second comparative example sample s8, third comparative example sample s9, and fourth comparative example sample s10). ) Was manufactured. And about a total of ten heat dissipation modules, the heat cycle test was done and temperature change tolerance was evaluated.

  FIG. 4 is an explanatory diagram showing the evaluation results of the temperature change resistance of the samples s1 to s10. In FIG. 4, the planar view shape of the second metal layer 13, the planar view shape of the first metal layer 11, the position d1, the position d2, and the evaluation results are shown for each of the samples s1 to s10. In addition, as a planar view shape of the 2nd metal layer 13, the length L1 (millimeter) of a longitudinal direction and the length L2 (millimeter) of a transversal direction are represented. Moreover, as the planar view shape of the 1st metal layer 11, the length L3 (millimeter) of a longitudinal direction and the length L4 (millimeter) of a transversal direction are represented. In addition, as described above, the position d1 refers to the second metal layer 13 when the outer peripheral end surface 12a of the ceramic substrate 12 is used as a reference (origin) and the −X direction and the + X direction are defined as plus and minus, respectively. It means the position of the outer peripheral end face 13a. The position d2 is the first metal layer when the outer peripheral end face 13a of the second metal layer 13 is defined as the reference (origin) and the −X direction and the + X direction are defined as plus and minus, respectively, as described above. 11 indicates the position of the outer peripheral end face 11a.

  In the manufacture of the samples s1 to s10, the first metal layer 11 and the second metal layer 13 were both made of aluminum (Al). In the manufacture of the samples s1 to s10, the ceramic substrate 12 was formed of aluminum nitride (AlN). The size of the ceramic substrate 12 in each of the samples s1 to s10 was as follows. That is, the length in the longitudinal direction of the ceramic substrate 12 in plan view is 34 mm, the length in the short direction of the ceramic substrate 12 in plan view is 20 mm, and the thickness of the ceramic substrate 12 is 0.635 mm. Met. Further, in each of the samples s1 to s10, the thickness of the joint portion 14 was 0.9 millimeter. In each sample s1 to s10, the length h1 of the fin 15 in the Z-axis direction was 5 millimeters, the pitch p1 of the fins 15 was 0.6 millimeters, and the thickness of the fins 15 was 0.25 millimeters.

  In the manufacture of the samples s1 to s10, brazing was performed using an Al—Si based brazing foil in step S110 (bonding between the layers) shown in FIG. In step S115, a circuit pattern was formed by chemical etching. In step S120, the fins 15 are formed by cutting and raising.

Samples s1 to s6 of each example satisfy the following two conditions (first condition and second condition).
First condition: When the outer peripheral end surface 12a of the ceramic substrate 12 is used as a reference (origin), and the −X direction and the + X direction are defined as plus and minus, respectively, the position of the outer peripheral end surface 13a of the second metal layer 13 is It is a plus. (In other words, the outer peripheral end surface 13a of the second metal layer 13 is located inside the outer peripheral end surface 12a of the ceramic substrate 12).
Second condition: When the outer peripheral end face 13a of the second metal layer 13 is used as a reference (origin), and the −X direction and the + X direction are respectively defined as plus and minus, the outer end face 11a of the first metal layer 11 The position d2 is not less than −1.5 millimeters and not more than +1.5 millimeters.

  On the other hand, the samples s7 to s10 of each comparative example did not satisfy either of the two conditions. Note that the samples s7 to s10 of each comparative example differ from the samples s1 to s6 of each example in that the samples s7 to s10 do not satisfy either of the above two conditions. It was the same as sample s1-s6 of an example.

  As a thermal cycle test, for each sample s1 to s10, a total of 3,000 times was repeated for 30 minutes in an environment of -40 degrees Celsius and for 30 minutes in an environment of +200 degrees Celsius. did.

  In each of the samples s1 to s10 after the thermal cycle test described above, generation of cracks in the ceramic substrate 12, peeling of the joint portion between the first metal layer 11 and the ceramic substrate 12, and the first metal layer 11 and the second metal layer 13 are performed. The presence or absence of peeling of the joint portion with (joint portion 14) was visually confirmed. And when cracks or peeling at any joint part occurs, the temperature change resistance is evaluated low ("X" in FIG. 4), and when cracks and peeling at both joint parts do not occur The temperature change resistance was highly evaluated (“◯” in FIG. 4).

  FIG. 5 is an explanatory diagram showing a detailed configuration of the sample s1 of the first embodiment. The uppermost, middle and lowermost stages in FIG. 5 correspond to the uppermost, middle and lowermost stages in FIG. 2, respectively.

  As shown in the middle part of FIG. 5, in the sample s1, the position d2 was 0 (zero). That is, in the sample s1 of the first example, the position along the X-axis direction of the outer peripheral end surface 11a of the first metal layer 11 coincides with the position along the X-axis direction of the outer peripheral end surface 13a of the second metal layer 13. It was. The sample s1 satisfied the first condition and the second condition described above.

  FIG. 6 is an explanatory diagram showing a detailed configuration of the sample s4 of the fourth embodiment. The top, middle, and bottom stages in FIG. 6 correspond to the top, middle, and bottom stages in FIG. 2, respectively.

  As shown in the middle part of FIG. 6, in the sample s4, the position d2 was minus (−1.5 millimeters). That is, in the sample s4 of the fourth example, the position along the X-axis direction of the outer peripheral end surface 11a of the first metal layer 11 is outside the position along the X-axis direction of the outer peripheral end surface 13a of the second metal layer 13. Met. Note that the sample s4 satisfied the first condition and the second condition described above.

  The detailed configuration of the sample s2 of the second example, the sample s3 of the third example, the sample s5 of the fifth example, and the sample s6 of the sixth example is the same as the detailed configuration of the heat dissipation module 10 of the embodiment shown in FIG. It was the same. Further, as shown in FIG. 4, these samples s2, s3, s5, and s6 all satisfied the first condition and the second condition described above.

  The detailed configuration of the sample s7 of the first comparative example was the same as the detailed configuration of the heat dissipation module 10 of the embodiment shown in FIG. The detailed configuration of the sample s8 of the second comparative example was the same as that of the sample s4 of the fourth example shown in FIG. However, as shown in FIG. 4, these samples s7 and s8 did not satisfy the second condition. Specifically, in the sample s7, the position d2 is +2.0 millimeters and does not satisfy the condition of +1.5 millimeters or less. Further, in the sample s8, the position d2 was −2.0 millimeters and did not satisfy the condition of −1.5 millimeters or more.

  FIG. 7 is an explanatory diagram showing a detailed configuration of the sample s9 of the third comparative example. The uppermost, middle and lowermost stages in FIG. 7 correspond to the uppermost, middle and lowermost stages in FIG. 2, respectively.

  7, in the sample s9, the position along the X-axis direction of the outer peripheral end surface 13a of the second metal layer 13 coincides with the position along the X-axis direction of the outer peripheral end surface 12a of the ceramic substrate 12. It was. Therefore, the sample s9 of the third comparative example did not satisfy the first condition described above. Note that the sample s9 satisfied the second condition described above.

  The detailed configuration of the sample s10 of the fourth comparative example is the same as the detailed configuration of the sample s9 of the third comparative example shown in FIG. However, as shown in FIG. 4, since the position d2 of the sample s9 is +2.5 millimeters, the sample s9 of the third comparative example did not satisfy the second condition in addition to the first condition described above.

  As shown in FIG. 4, the evaluation results of the samples s1 to s6 of each example were high evaluation “◯”. On the other hand, the evaluation result of s7-s10 of each comparative example was low evaluation "x". Since the samples s7 to s10 of each comparative example did not satisfy at least one of the first condition and the second condition described above, the occurrence of cracks in the ceramic substrate 12, the first metal layer 11 and the ceramic substrate 12 It is presumed that at least one of the peeling of the joining portion and the peeling of the joining portion between the first metal layer 11 and the second metal layer 13 (joining portion 14) occurred.

  On the other hand, since the samples s1 to s6 of each example satisfied both the first condition and the second condition described above, generation of cracks in the ceramic substrate 12, the first metal layer 11 and the ceramic substrate 12 It is presumed that neither the peeling of the bonding portion nor the peeling of the bonding portion between the first metal layer 11 and the second metal layer 13 (bonding portion 14) occurred. That is, in the samples s1 to s6 of each example, the outer peripheral end (outer peripheral end surface 13a) of the second metal layer 13 was positioned inside the outer peripheral end (outer peripheral end surface 12a) of the ceramic substrate 12. For this reason, when the second metal layer 13 is about to shrink or extend as the temperature changes, the second metal layer 13 does not exist in the vicinity of the outer peripheral edge of the ceramic substrate 12. It is presumed that generation of cracks in the vicinity of the outer peripheral edge and peeling of the joint portion were suppressed. In addition, in the samples s1 to s6 of each example, the position d2 of the outer peripheral end surface 11a of the first metal layer 11 is 1.5 mm or less on the inner side with respect to the outer peripheral end surface 13a of the second metal layer 13, and the outer side Therefore, when the first metal layer 11 and the second metal layer 13 try to shrink or extend as the temperature changes, the first surface S1 and the first surface S1 of the ceramic substrate 12 It is presumed that the stress applied to the two surfaces S2 could be canceled. For this reason, generation | occurrence | production of the crack in the ceramic substrate 12, peeling of the junction part of the 1st metal layer 11 and the ceramic substrate 12, and peeling of the junction part of the 1st metal layer 11 and the 2nd metal layer 13 (joining part 14) are carried out. It is estimated that none of these occurred.

  In the samples s1 to s6 of each example, the fin 15 has a small thickness and the cross-sectional shape of the fin 15 is an arcuate shape. Therefore, the fin 15 is deformed due to a temperature change. easy. For this reason, since the second metal layer 13 as a whole is easily deformed with a temperature change, the stress applied to the ceramic substrate 12 is large. However, it is presumed that, by satisfying the first condition and the second condition, the generation of cracks and the separation of the joint portion could be suppressed.

C. Variation:
C1. Modification 1:
In the above embodiment and each example, the outer peripheral end surface 11a of the first metal layer 11 and the outer peripheral end surface 13a of the second metal layer 13 are both parallel to the thickness direction (Z-axis direction). It is not limited to this. FIG. 8 is a cross-sectional view showing a detailed configuration of the first aspect of the heat dissipation module in the modification.

  The heat dissipation module 10 a of the first aspect in the modification shown in FIG. 8 includes a first metal layer 11 b instead of the first metal layer 11, and a second metal layer 13 b instead of the second metal layer 13. Unlike the heat dissipation module 10 of the above embodiment, the other configurations are the same as those of the heat dissipation module 10 of the embodiment.

  The outer peripheral end surface of the first metal layer 11b is not parallel to the thickness direction (Z-axis direction). Specifically, the outer peripheral end surface of the first metal layer 11b has a shape that spreads outward as it goes in the + Z direction. Therefore, the cross-sectional shape of the first metal layer 11b is a tapered shape in which the length in the X-axis direction becomes shorter toward the −Z direction.

  The second metal layer 13b is different from the second metal layer 13 of the above-described embodiment in that the second metal layer 13b includes a joint 14b instead of the joint 14, and other configurations are the same as those of the second metal layer 13 of the embodiment. It is.

  The outer peripheral end surface of the second metal layer 13b (the outer peripheral end surface of the bonding portion 14b) is not parallel to the thickness direction (Z-axis direction). Specifically, the outer peripheral end surface of the second metal layer 13b (the outer peripheral end surface of the joint portion 14b) has a shape that shrinks inward as it goes in the + Z direction. Therefore, the cross-sectional shape of the joint portion 14b is a taper shape such that the length in the X-axis direction becomes shorter toward the + Z direction.

The heat dissipation module 10a of the first aspect in the modified example having such a configuration satisfies the following two conditions (third condition and fourth condition).
Third condition: When the outer peripheral end surface 12a of the ceramic substrate 12 is used as a reference (origin) and the −X direction and the + X direction are defined as plus and minus, respectively, the second metal layer 13b comes into contact with the ceramic substrate 12. The position d1a of the outer peripheral end c2 of the contact surface S12 is positive. (In other words, the outer peripheral end c2 of the contact surface S12 of the second metal layer 13b is located inside the outer peripheral end surface 12a of the ceramic substrate 12).
Fourth condition: When the outer peripheral edge c2 of the contact surface S12 of the second metal layer 13b is set as a reference (origin) and the −X direction and the + X direction are defined as plus and minus, respectively, in the first metal layer 11b The position d2a of the outer peripheral end c1 of the contact surface S11 in contact with the ceramic substrate 12 is −1.5 millimeters or more and +1.5 millimeters or less.

  By satisfying the third condition and the fourth condition described above, the heat dissipation module 10a of the first aspect in the modified example can achieve the same effects as the heat dissipation module 10 of the above embodiment.

  FIG. 9 is a cross-sectional view showing a detailed configuration of the heat dissipation module of the second aspect in the modification. The heat dissipation module 10 b of the second aspect in the modification shown in FIG. 9 includes a first metal layer 11 c instead of the first metal layer 11, and a second metal layer 13 c instead of the second metal layer 13. Unlike the heat dissipation module 10 of the above embodiment, the other configurations are the same as those of the heat dissipation module 10 of the embodiment.

  The outer peripheral end face of the first metal layer 11c is not parallel to the thickness direction (Z-axis direction), like the first metal layer 11b of the first aspect in the modification. Specifically, the outer peripheral end surface of the first metal layer 11c has a shape that spreads outward as it goes in the -Z direction. Therefore, the cross-sectional shape of the first metal layer 11c is a taper shape such that the length in the X-axis direction becomes shorter toward the + Z direction.

  The second metal layer 13c is different from the second metal layer 13 of the above-described embodiment in that the second metal layer 13c includes a joint 14c instead of the joint 14, and the other configuration is the same as the second metal layer 13 of the embodiment. It is.

  The outer peripheral end surface of the second metal layer 13c (the outer peripheral end surface of the joint portion 14c) is not parallel to the thickness direction (Z-axis direction), like the second metal layer 13b of the first aspect in the modification. Specifically, the outer peripheral end surface of the second metal layer 13c (the outer peripheral end surface of the joint portion 14c) has a shape that shrinks inward as it goes in the −Z direction. Therefore, the cross-sectional shape of the joint portion 14c is a taper shape in which the length in the X-axis direction becomes shorter toward the −Z direction.

The heat dissipation module 10b of the second aspect in the modified example having such a configuration satisfies the following two conditions (fifth condition and sixth condition).
Fifth condition: When the outer peripheral end surface 12a of the ceramic substrate 12 is used as a reference (origin) and the −X direction and the + X direction are defined as plus and minus, respectively, the second metal layer 13c comes into contact with the ceramic substrate 12. The position d1b of the outer peripheral end c4 of the contact surface S22 is positive. (In other words, the outer peripheral end c4 of the contact surface S22 of the second metal layer 13c is positioned inside the outer peripheral end surface 12a of the ceramic substrate 12).
Sixth condition: When the outer peripheral edge c4 of the contact surface S22 of the second metal layer 13c is set as a reference (origin) and the −X direction and the + X direction are defined as plus and minus, respectively, in the first metal layer 11c The position d2b of the outer peripheral end c3 of the contact surface S21 in contact with the ceramic substrate 12 is −1.5 millimeters or more and +1.5 millimeters or less.

  By satisfying the fifth condition and the sixth condition described above, the heat dissipation module 10b of the second aspect in the modified example can achieve the same effects as the heat dissipation module 10 of the above embodiment.

The third condition and the fifth condition described above are substantially equal and can be expressed as the following seventh condition. The fourth condition and the sixth condition described above are substantially equal and can be expressed as the following eighth condition.
Seventh condition: contact that contacts the ceramic substrate 12 in the second metal layer when the outer peripheral end surface 12a of the ceramic substrate 12 is used as a reference (origin) and the −X direction and the + X direction are defined as plus and minus, respectively. The position of the outer peripheral edge of the surface is positive. (In other words, the outer peripheral end of the contact surface of the second metal layer is located inside the outer peripheral end surface of the ceramic substrate 12).
Eighth condition: When the outer peripheral edge of the contact surface of the second metal layer is used as a reference (origin) and the −X direction and the + X direction are defined as plus and minus, respectively, the first metal layer contacts the ceramic substrate. The position of the outer peripheral edge of the contact surface is −1.5 mm or more and +1.5 mm or less.

  Here, when the first condition is satisfied, the seventh condition is satisfied. Similarly, when the second condition described above is satisfied, the eighth condition is satisfied. Therefore, the heat dissipation module satisfying at least the seventh condition and the eighth condition described above can be applied to the heat dissipation module of the present invention.

C2. Modification 2:
In the embodiment and each example described above, the metal plate 23 that is the base material of the second metal layer 13 is a metal whose length in the X-axis direction is previously shorter than the length of the ceramic substrate 22 in the X-axis direction. Although the board was used, this invention is not limited to this. For example, as the base material of the second metal layer 13, a metal plate whose length in the X-axis direction is equal to or longer than the length of the ceramic substrate 22 in the X-axis direction may be used. In such a configuration, after step S110 (before step S115 or after step S115), the peripheral portion of the metal plate that is the base material of the second metal layer 13 is processed, and the length of the metal plate in the X-axis direction is thus increased. Is preferably shorter than the length of the ceramic substrate 22 in the X-axis direction.

  Further, for example, as a base material of the second metal layer 13, a metal plate whose length in the X-axis direction is equal to or longer than the length of the ceramic substrate 22 in the X-axis direction (hereinafter referred to as “first metal plate”); A metal plate (hereinafter referred to as “second metal plate”) having a length in the X-axis direction shorter than the length in the X-axis direction of the ceramic substrate 22 is prepared, and the second metal is formed on the second surface S2 of the ceramic substrate 12. A plate may be joined and a 1st metal plate may be joined to the surface opposite to the surface where the ceramic substrate 12 was joined in a 2nd metal plate. In this configuration, it is preferable to form the fins 15 on the first metal plate in step S120. Even in such a configuration, the outer peripheral end (outer peripheral end face) of the second metal plate joined to the ceramic substrate 12 can be located inside the outer peripheral end (outer peripheral end face 12a) of the ceramic substrate 12. In this configuration, the first metal plate and the second metal plate after the fins 15 are formed correspond to the second metal layer in the claims.

C3. Modification 3:
In the said embodiment and each Example, although the cross-sectional shape of the fin 15 was the shape curved in circular arc shape, this invention is not limited to this. For example, a shape bent at an acute angle may be used. Moreover, it is good also as a shape extended linearly, without curving or bending.

C4. Modification 4:
In the embodiment and each example, the semiconductor module 100 includes the first case 110 and the lid 113, but the first case 110 and the lid 113 may be omitted. In the semiconductor module 100, the second case 112 may be omitted.

  FIG. 10 is a cross-sectional view showing a configuration of a semiconductor module 100a in a modified example. The semiconductor module 100 a includes a first case 110, a lid 113, and a second case 112, a resin mold 215 instead of the resin 115, and an external terminal 211 instead of the external terminal 111. The semiconductor module 100 is different from the semiconductor module 100 of the embodiment shown in FIG. 1 in that the wiring 214 is provided instead of the wiring 114.

  The resin mold 215 covers the heat dissipation module 10 excluding the fins 15, a part of the external terminal 211, and the wiring 214. The resin mold 215 is formed of resin (for example, epoxy resin). The external terminal 211 has a bent external shape, a part thereof is disposed in the resin mold 215, and the remaining part is exposed from the resin mold 215. The external terminal 211 is made of a conductive material. The wiring 214 is a thin metal wire like the wiring 114, and electrically connects the external terminal 211 and the semiconductor element 50, and electrically connects the external terminal 211 and the heat dissipation module 10 (first metal layer 11). Connect to.

  The semiconductor module 100a having such a configuration has the same effect as the semiconductor module 100 of the embodiment.

  In the embodiment and each example described above, a space surrounded by the lid 113 and the first case 110 in the semiconductor module 100 (a space excluding the heat dissipation module 10, the semiconductor element 50, and the wiring 114) is made of resin. 115 is filled, but the resin 115 may be omitted. Moreover, in the said embodiment and each Example, although the external terminal 111 was arrange | positioned inside the 1st case 110, it replaced with the inside of the 1st case 110, and was surrounded by the 1st case 110 and the lid | cover 113. You may arrange | position in the space (space filled with resin 115). In this configuration, for example, the external terminals can be arranged so as to extend from the first metal layer 11 of the heat dissipation module 10 in the Z-axis direction (+ Z direction) and to be partially exposed from the lid 113.

C5. Modification 5:
FIG. 11 is a plan view showing the configuration of the heat dissipation module of the third to fifth aspects in the modification. Fig.11 (a) is a top view which shows the 3rd aspect of the thermal radiation module in a modification. Moreover, FIG.11 (b) is a top view which shows the 4th aspect of the thermal radiation module in a modification, and FIG.11 (c) is respectively a 5th aspect of the thermal radiation module in a modification.

  In the said embodiment and each Example, as shown, for example in FIG. 2, the planar view shape of the 1st metal layer 11 was a rectangle, However, This invention is not limited to this. In the heat dissipation module 10c shown in FIG. 11A, the first metal layer 11d includes two regions (region 81a and region 81b). Each of the regions 81a and 81b has a rectangular external appearance shape (planar shape), and is disposed at a predetermined distance from each other in the X-axis direction. The planar view shape of the first metal layer 11d having such a configuration as a whole is a rectangle.

  In the heat dissipation module 10d shown in FIG. 11B, the first metal layer 11e is composed of two regions (region 81c and region 81d). The region 81c has an external shape (planar shape) in which one of the four corners of the rectangle is cut out into a rectangle. The region 81d has a smaller area than the region 81c and has a rectangular external shape (planar shape). The region 81d is arranged at a notched portion in the region 81c, and the planar view shape of the first metal layer 11e as a whole is a rectangle.

  In the heat dissipation module 10e shown in FIG. 11C, the first metal layer 11f includes four regions (region 81e, region 81f, region 81g, and region 81h). The other three regions 81e, 81g, 81h excluding the region 81f all have a rectangular external shape (planar shape). The region 81f has the same shape as the region 81c shown in FIG. The planar view shape of the first metal layer 11f having such a configuration as a whole is a rectangle.

  In the heat dissipation modules of the third to fifth aspects described above, the shape of the first metal layers 11d, 11e, and 11f in plan view is not exactly rectangular. However, when the plurality of regions constituting the first metal layers 11d, 11e, and 11f are viewed as a whole, the planar view shape of the first metal layers 11d, 11e, and 11f is a rectangle. In other words, the planar shape of the first metal layers 11d, 11e, and 11f is a divided rectangle. The heat dissipation modules 10c, 10d, and 10e of the third to fifth aspects having such a configuration have the same effects as the heat dissipation module 10 of the above embodiment.

  The present invention is not limited to the above-described embodiments and modifications, and can be realized with various configurations without departing from the spirit thereof. For example, the technical features in the embodiments and the modifications corresponding to the technical features in each embodiment described in the summary section of the invention are to solve some or all of the above-described problems, or In order to achieve part or all of the effects, replacement or combination can be performed as appropriate. Further, if the technical feature is not described as essential in the present specification, it can be deleted as appropriate.

DESCRIPTION OF SYMBOLS 10, 10a, 10b, 10c, 10d, 10e ... Radiation module 11 ... 1st metal layer 11a ... Outer peripheral end surface 11b, 11c, 11d, 11e, 11f ... First metal layer 12 ... Ceramic substrate 12a ... Outer peripheral end surface 13, 13c ... 2nd metal layer 13a ... Outer peripheral end surface 13b ... 2nd metal layer 14, 14b, 14c ... Joining part 15 ... Fin 21 ... Metal plate 22 ... Ceramic substrate 23 ... Metal plate 50 ... Semiconductor element 60 ... Cutlery 81a, 81b, 81c, 81d, 81e, 81f, 81g, 81h ... area 100, 100a ... semiconductor module 109 ... protruding portion 110 ... first case 111 ... external terminal 112 ... second case 113 ... lid 114 ... wiring 115 ... resin 211 ... external terminal 214 ... Wiring S1 ... first surface S2 ... second surface S11, S12, S21, S22 ... contact Surface c1, c2, c3, c4 ... outer peripheral edge d1, d2, d1a, d2a, d1b, d2b ... position

Claims (7)

A ceramic substrate having a first surface located at one end in the thickness direction and a second surface located at the other end in the thickness direction;
A first metal layer having a first contact surface in contact with the first surface;
A second metal layer in contact with the second surface and having fins for heat dissipation formed thereon;
A heat dissipation module comprising:
The first outer peripheral end that is the outer peripheral end of the first contact surface is 1.5 mm or less on the inner side and 1.5 mm or less on the outer side with reference to the second outer peripheral end that is the outer peripheral end of the second contact surface. Placed in position,
The second outer peripheral end is located on the inner side of the third outer peripheral end which is the outer peripheral end of the ceramic substrate;
A heat dissipation module. In the heat dissipation module according to claim 1,
The first metal layer includes a first outer peripheral end surface including the first outer peripheral end and parallel to the thickness direction,
The second metal layer has a second outer peripheral end surface including the second outer peripheral end and parallel to the thickness direction,
The third outer peripheral end of the ceramic substrate is a third outer peripheral end surface parallel to the thickness direction;
In a predetermined direction perpendicular to any of the thickness direction, the first outer peripheral end surface, the second outer peripheral end surface, and the third outer peripheral end surface, the position of the first outer peripheral end surface is the same as the position of the second outer peripheral end surface. As a reference, the position is 1.5 mm or less on the inside along the predetermined direction and 1.5 mm or less on the outside along the predetermined direction,
In the predetermined direction, the position of the second outer peripheral end surface is inside the position of the third outer peripheral end surface;
A heat dissipation module. In the heat dissipation module according to claim 1 or 2,
The fin is formed by cutting and raising the base material of the second metal layer;
A heat dissipation module. In the heat dissipation module according to any one of claims 1 to 3,
A plurality of the fins are formed in the second metal layer,
The length in the thickness direction of each fin is 3 mm or more and 7 mm or less,
The pitch of the adjacent fins is 0.2 mm or more and 1.0 mm or less,
The thickness of each fin is 0.1 mm or more and 0.5 mm or less,
A heat dissipation module. In the heat dissipation module according to any one of claims 1 to 4,
The second metal layer has the fin, and a joint portion joined to the fin and the second surface,
The length in the thickness direction of the joint is 0.5 mm or more and 1.5 mm or less;
A heat dissipation module. A semiconductor module comprising the heat dissipation module according to any one of claims 1 to 5,
A semiconductor element is bonded to the first metal layer,
The semiconductor element, the first metal layer, and the ceramic substrate are covered with a resin;
A semiconductor module characterized by the following. A semiconductor module comprising the heat dissipation module according to any one of claims 1 to 5,
A semiconductor element is bonded to the first metal layer,
Comprising a case covering the semiconductor element and the heat dissipation module;
A semiconductor module characterized by the following.

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