Method of manufacturing semiconductor device and semiconductor device

Abstract

To prevent misalignment of bonding members when bonding an insulating substrate on which semiconductor devices are mounted and a heat-dissipating member with a bonding member.SOLUTION: A method for manufacturing a semiconductor device having a semiconductor package with a heat dissipation layer formed on one or both sides, a heat dissipation member joined to the heat dissipation layer, and a bonding member joining the heat dissipation layer and the heat dissipation member, includes a temporary bonding process in which the bonding member is locally joined to the heat dissipation layer or the bonding member.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing a semiconductor device and a semiconductor device.

Background Art

[0002] Semiconductor products using power semiconductor devices typified by IGBTs (Insulated Gate Bipolar Transistors) have been used in recent years. In recent semiconductor products, higher power, higher integration, and higher reliability are required. With the higher power and higher integration of products, high heat dissipation is required to dissipate the heat generated in semiconductor devices.

[0003] For example, Patent Document 1 discloses a cooler-integrated semiconductor module including a semiconductor module having an insulating wiring board and a semiconductor device, and a cooler thermally connected to the semiconductor module. Patent Document 1 discloses that the cooler is directly bonded to a metal layer on the lower surface side of the insulating wiring board via a solder layer.

[0004] Patent Document 2 discloses that by bonding a semiconductor device to each metal wiring board via a bonding material composed of a sintered material, the thermal conductivity is improved and the exhaust heat performance is enhanced.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] Heat dissipation of a semiconductor element is performed using a heat dissipation member connected to an insulating substrate on which the semiconductor element is mounted. In particular, in order to enhance the cooling performance, a joining member such as a plate solder is used as a connection method with high thermal conductivity.

[0007] In order to efficiently cool a semiconductor element, it is necessary to join the insulating substrate on which the semiconductor element is mounted and the heat dissipation member so that heat is sufficiently transferred therebetween. In order to sufficiently perform heat transfer between the insulating substrate on which the semiconductor element is mounted and the heat dissipation member, it is required to attach the joining member with high positional accuracy.

[0008] An object of the present disclosure is to prevent displacement of a joining member when joining an insulating substrate on which a semiconductor element is mounted and a heat dissipation member with the joining member.

Means for Solving the Problems

[0009] According to one aspect of the present disclosure, there is provided a method for manufacturing a semiconductor device including a semiconductor package having a heat dissipation layer formed on one or both surfaces, a heat dissipation member joined to the heat dissipation layer, and a joining member joining the heat dissipation layer and the heat dissipation member, the method including a temporary joining step of locally joining the joining member to the heat dissipation layer or the joining member.

Effects of the Invention

[0010] According to each embodiment of the present disclosure, displacement of a joining member can be prevented when joining an insulating substrate on which a semiconductor element is mounted and a heat dissipation member with the joining member.

Brief Description of the Drawings

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Embodiments for Carrying Out the Invention

[0012] Hereinafter, each embodiment of the present invention will be described with reference to the accompanying drawings. Note that, regarding the description in the specification and drawings according to each embodiment, for components having substantially the same or corresponding functional configurations, the same reference numerals may be given, and overlapping descriptions may be omitted. Also, for ease of understanding, the scales of each part in the drawings may be different from the actual ones.

[0013] In directions such as parallel, right angle, orthogonal, horizontal, vertical, up and down, left and right, etc., a deviation that does not impair the effects of the embodiment is allowed. The shape of the corners is not limited to a right angle and may be rounded in an arc shape. Parallel, right angle, orthogonal, horizontal, and vertical may include substantially parallel, substantially right angle, substantially orthogonal, substantially horizontal, and substantially vertical.

[0014] <<First Embodiment>> <Semiconductor device 1> To explain the manufacturing method of the semiconductor device according to the first embodiment, a semiconductor device 1 which is an example of a semiconductor device manufactured by the manufacturing method of the semiconductor device according to the first embodiment will be described.

[0015] FIG. 1 is a perspective view of a semiconductor device 1 which is an example of a semiconductor device manufactured by the manufacturing method of the semiconductor device according to the first embodiment. FIG. 2 is an exploded perspective view of the semiconductor device 1. FIG. 3 is a bottom view of the insulating substrate 10 of the semiconductor device 1.

[0016] Note that, for convenience of explanation, an XYZ orthogonal coordinate system may be set in the drawings. For the coordinate axes perpendicular to the plane of the drawing, a cross mark in the circle of the coordinate axis indicates that the direction into the paper is positive, and a black dot in the circle indicates that the direction toward the front side of the paper is positive. However, the coordinate system is defined for the purpose of explanation and does not limit the posture of the semiconductor device or the like.

[0017] In the present disclosure, unless otherwise specified, the X axis is a direction parallel to the mounting surface of the heat dissipation member 20, the Y axis is a direction parallel to the mounting surface of the heat dissipation member 20 and perpendicular to the X axis, and the Z axis is a direction perpendicular to the X axis and the Y axis. Note that the Z-axis direction may be referred to as the vertical direction. For example, the +Z side may be the upper side and the -Z side may be the lower side. A plan view seen from the +Z side may be referred to as a top view, and a plan view seen from the -Z side may be referred to as a bottom view.

[0018] The semiconductor device 1 includes an insulating substrate 10, a heat dissipation member 20, and a bonding member 30. Each component will be described.

[0019] [Insulating substrate 10] The insulating substrate 10 is a substrate on which a semiconductor element is mounted. The insulating substrate 10 includes an insulator layer 12, a wiring layer 14 formed on one surface (+Z side surface) of the insulator layer 12, and a heat dissipation layer 16 formed on the other surface (-Z side surface) of the insulator layer 12.

[0020] A semiconductor element is mounted on the wiring layer 14 of the insulating substrate 10. The semiconductor element to be mounted is, for example, an IGBT, a power MOSFET (Metal Oxide Semiconductor Field Effect Transistor), a FWD (Free Wheeling Diode), or the like.

[0021] Also, the semiconductor element to be mounted may be an RB-IGBT (Reverse Blocking-Insulated Gate Bipolar Transistor) in which the aforementioned IGBT and FWD are integrated on one chip. Furthermore, the semiconductor element to be mounted may be an RC-IGBT (Reverse Conducting-Insulated Gate Bipolar Transistor) in which the aforementioned IGBT and FWD are integrated on one chip.

[0022] (Insulator layer 12) The insulator layer 12 is a layer formed of an insulator. The insulator layer 12 is formed of, for example, ceramic or silicon carbide. The thickness of the insulator layer 12 is, for example, from 0.3 mm to 0.6 mm.

[0023] (Wiring layer 14) The wiring layer 14 is a layer that forms wiring electrically connected to the mounted semiconductor element. The wiring layer 14 is formed on one main surface of the insulator layer 12. The semiconductor element is mounted on the +Z side surface of the wiring layer 14. Wiring for connecting to the semiconductor element is formed in the wiring layer 14. In the drawings of the present case, such as FIG. 1, the wiring pattern of the wiring layer 14 is omitted. The wiring layer 14 is formed of a conductive material, for example, copper. The thickness of the wiring layer 14 is, for example, from 0.3 mm to 1 mm.

[0024] (Heat dissipation layer 16) The heat dissipation layer 16 is a layer for dissipating the heat from the semiconductor element laminated on the wiring layer 14 to the outside of the insulating substrate 10. The heat dissipation layer 16 is formed on one main surface of the insulator layer 12. The heat dissipation layer 16 is formed of the same conductive material as the wiring layer 14, for example, copper. The heat dissipation layer 16 has a surface 16S on the -Z side. The thickness of the heat dissipation layer 16 is, for example, from 0.3 mm to 1 mm. Since the heat dissipation layer 16 is formed of a conductive material, it also acts as an electrostatic shield.

[0025] Note that the heat dissipation layer 16 is preferably formed thick in order to dissipate heat and prevent warping of the substrate. Also, the heat dissipation layer 16 and the wiring layer 14 are preferably made to have the same thickness in order to prevent warping of the substrate.

[0026] [Heat dissipation member 20] The heat dissipation member 20 is a member for discharging the heat from the insulating substrate 10 to the outside. The heat dissipation member 20 is, for example, a heat dissipation plate formed of metal or a liquid-cooled cooler (see, for example, the heat dissipation members 120 and 121 in FIG. 22) through which a coolant flows inside. The heat dissipation layer 16 of the insulating substrate 10 is joined to the mounting surface 20S of the heat dissipation member 20 via the joining member 30. The heat dissipation member 20 dissipates the heat of the insulating substrate 10 by connecting to the heat dissipation layer 16 of the insulating substrate 10 via the joining member 30.

[0027] By using, for example, a heat dissipation plate formed of metal as the heat dissipation member 20, the heat dissipation member 20 transfers the heat from the mounting surface to the surface opposite to the mounting surface and dissipates the heat. By making the size of the heat dissipation member 20 larger than that of the insulating substrate 10, the heat dissipation area can be increased, and the heat dissipation efficiency can be improved to increase the efficiency of cooling the insulating substrate 10. Also, by using, for example, a liquid-cooled cooler as the heat dissipation member 20, the efficiency of cooling the insulating substrate 10 can be increased by a liquid (for example, water, antifreeze, or coolant liquid, etc.) that conducts inside the liquid-cooled cooler.

[0028] [Joining member 30] The joining member 30 is a member that joins the heat dissipation layer 16 of the insulating substrate 10 and the heat dissipation member 20. The joining member 30 is, for example, a solder paste. The joining member 30 is substantially rectangular in a bottom view. Also, the thickness of the joining member 30 is uniform.

[0029] <Method for manufacturing a semiconductor device according to the first embodiment> A method for manufacturing a semiconductor device according to the first embodiment will be described. FIGS. 4 to 9 are diagrams for explaining the method for manufacturing a semiconductor device according to the first embodiment.

[0030] First, the insulating substrate 10 is arranged such that the heat dissipation layer 16 faces upward. Then, the joining member 30 is moved along the arrow A1 (FIG. 4). As the joining member 30 is moved along the arrow A1, the joining member 30 is placed on the surface 16S of the heat dissipation layer 16 of the insulating substrate 10 (FIGS. 5 and 6).

[0031] With respect to the insulating substrate 10 on which the joining member 30 is placed, from the surface 30S1 side of the joining member 30 opposite to the insulating substrate 10 side, the heat dissipation layer 16 and the joining member 30 are locally joined by the local joining portion 50 (FIGS. 7 and 8). The local joining portion 50 is, for example, a laser bonder or an ultrasonic bonder.

[0032] The laser bonder locally irradiates a laser to the portion to be joined to melt the joining target. Then, as the melted joining target solidifies, the joining targets are joined together.

[0033] The ultrasonic bonder locally joins at the tip portion of the joining tool by causing the interfacial surface between the joining members to rub against each other by vibrating the tip of the joining tool ultrasonically.

[0034] First, the local joining portion 50 is moved to the spot SP1. Then, by the local joining portion 50, the heat dissipation layer 16 and the joining member 30 are locally joined at the portion (spot SP1) where the local joining portion 50 is located.

[0035] Next, the local joint 50 is moved to the spot SP2 along the arrow B1. During the movement of the local joint 50 along the arrow B1, the local joint 50 does not join the heat dissipation layer 16 and the joining member 30.

[0036] Then, at the spot SP2, the local joint 50 locally joins the heat dissipation layer 16 and the joining member 30.

[0037] Similarly, the local joint 50 is moved to the spot SP3 along the arrow B2, and at the spot SP3, the heat dissipation layer 16 and the joining member 30 are locally joined. Also, the local joint 50 is moved to the spot SP4 along the arrow B3, and at the spot SP4, the heat dissipation layer 16 and the joining member 30 are locally joined.

[0038] By locally joining the heat dissipation layer 16 and the joining member 30 at the spots SP1, SP2, SP3, and SP4 by the local joint 50, the joining member 30 is temporarily joined to the heat dissipation layer 16.

[0039] In the above description, the temporary joining is performed at a total of 4 locations, but if it is one or more locations, the number of locations for temporary joining is not limited.

[0040] Then, the insulating substrate 10 with the joining member 30 temporarily joined is placed on the placement surface 20S of the heat dissipation member 20 so that the joining member 30 contacts the heat dissipation member 20 (Fig. 9). Then, by heating the heat dissipation member 20 on which the insulating substrate 10 is placed, the insulating substrate 10 and the heat dissipation member 20 are joined by the joining member 30.

[0041] As a joining method using solder as the joining member 30, heating is performed in a reducing gas atmosphere such as hydrogen or formic acid for the purpose of non-cleaning to perform joining. By joining the insulating substrate 10 and the heat dissipation member 20 with the joining member 30, the insulating substrate 10 and the heat dissipation member 20 can be connected with high thermal conductivity.

[0042] <Function and Effect> In the method for manufacturing a semiconductor device according to the first embodiment, the bonding member 30 is temporarily bonded to the insulating substrate 10, and then the insulating substrate 10 and the heat dissipation member 20 are bonded together with the bonding member 30. By temporarily bonding the bonding member 30 to the insulating substrate 10, and then bonding the insulating substrate 10 and the heat dissipation member 20 together with the bonding member 30, the insulating substrate 10 and the bonding member 30 can be easily aligned. Furthermore, after the alignment of the insulating substrate 10 and the bonding member 30 has been completed, the bonding member 30 can be prevented from moving relative to the insulating substrate 10 and becoming misaligned.

[0043] Here, a reference example for comparison will be described. Figure 30 is a diagram for explaining the assembly of a semiconductor device 1z of the reference example.

[0044] The semiconductor device 1z of the reference example includes an insulating substrate 10z, a heat dissipation member 20z, and a bonding member 30z. Here, as an example, a semiconductor element 70z is bonded to the insulating substrate 10z via a bonding layer 40z.

[0045] In the semiconductor device 1z, when the insulating substrate 10z is joined to the heat dissipation member 20z using the joining member 30z, it is necessary to prevent the joining member 30z, which is a plate solder, from shifting in position. In the semiconductor device 1z of the reference example, a mold 81z and a mold 82z are used to prevent the joining member 30z from shifting in position. The mold 81z and the mold 82z are made of, for example, aluminum or carbon.

[0046] However, warping of the components or mold of the semiconductor device 1z may cause misalignment of the bonding member 30z. Furthermore, the molds 81z and 82z must be manufactured with high precision, which increases manufacturing costs. Furthermore, the use and management of the molds 81z and 82z requires man-hours. Furthermore, it takes time to align the molds.

[0047] In the manufacturing method of the semiconductor device according to the first embodiment, the bonding member 30 is temporarily bonded to the insulating substrate 10, and then the insulating substrate 10 and the heat dissipation member 20 are bonded with the bonding member 30, thereby preventing misalignment of the bonding member 30.

[0048] Note that the insulating substrate 10 having the wiring layer 14 on which the semiconductor element is mounted and the heat dissipation layer 16 is an example of a semiconductor package in which the heat dissipation layer is formed on one side.

[0049] <Modification Example> When temporarily joining the joining member 30 to the heat dissipation layer 16, it is not limited to joining at points such as the spots SP1, SP2, SP3, and SP4. For example, when temporarily joining, it may be temporarily joined linearly.

[0050] FIG. 10 is a diagram for explaining a modification of the method for manufacturing a semiconductor device according to the first embodiment. The local joint portion 50 may be continuously joined along the arrow C1 from the upper left corner of FIG. 10. That is, it may be continuously joined along the arrow C1. By continuously joining, it may be joined in the linear region SL1.

[0051] Note that, as shown in FIG. 10, it is desirable to continuously join so as to border the outer periphery of the joining member 30.

[0052] <<Second Embodiment>> <Method for Manufacturing a Semiconductor Device According to the Second Embodiment> The method for manufacturing a semiconductor device according to the second embodiment will be described. FIGS. 11 to 15 are diagrams for explaining the method for manufacturing a semiconductor device according to the second embodiment. In the method for manufacturing a semiconductor device according to the second embodiment, the joining member 30 is temporarily joined to the heat dissipation member 20.

[0053] First, the joining member 30 is moved along the arrow A11 toward the heat dissipation member 20 (FIG. 11). By moving the joining member 30 along the arrow A11, the joining member 30 is placed on the placement surface 20S of the heat dissipation member 20 (FIG. 12).

[0054] With respect to the heat dissipation member 20 on which the joining member 30 is placed, from the surface 30S2 side of the joining member 30 opposite to the heat dissipation member 20 side, the heat dissipation layer 16 and the joining member 30 are locally joined by the local joint portion 50 (FIGS. 13 and 14).

[0055] First, the local joint 50 is moved to the spot SP11. Then, the heat dissipation member 20 and the joint member 30 are locally joined at the portion (spot SP11) where the local joint 50 is located by the local joint 50.

[0056] Next, the local joint 50 is moved to the spot SP12 along the arrow B11. Note that while the local joint 50 is being moved along the arrow B11, the local joint 50 does not join the heat dissipation member 20 and the joint member 30.

[0057] Then, at the spot SP12, the local joint 50 locally joins the heat dissipation member 20 and the joint member 30.

[0058] Similarly, the local joint 50 is moved to the spot SP13 along the arrow B12, and at the spot SP13, the heat dissipation member 20 and the joint member 30 are locally joined. Also, the local joint 50 is moved to the spot SP14 along the arrow B13, and at the spot SP14, the heat dissipation member 20 and the joint member 30 are locally joined.

[0059] By locally joining the heat dissipation member 20 and the joint member 30 at the spots SP|1, SP12, SP13, and SP14 by the local joint 50, the joint member 30 is temporarily joined to the heat dissipation member 20.

[0060] Then, the heat dissipation member 20 with the joint member 30 temporarily joined is placed on the joint member 30 on the mounting surface 20S of the heat dissipation member 20 so that the joint member 30 contacts the heat dissipation layer 16 of the insulating substrate 10 (FIG. 15). Then, by heating the heat dissipation member 20 on which the insulating substrate 10 is placed, the insulating substrate 10 and the heat dissipation member 20 are joined by the joint member 30.

[0061] In the method for manufacturing a semiconductor device according to the second embodiment, by temporarily joining the joint member 30 to the heat dissipation member 20 and then joining the insulating substrate 10 and the heat dissipation member 20 by the joint member 30, displacement of the joint member 30 can be prevented.

[0062] <Modification Example> When temporarily joining the joining member 30 to the heat dissipation member 20, it is not limited to joining at points such as spots SP11, SP12, SP13, and SP14. For example, when temporarily joining, it may be temporarily joined linearly.

[0063] FIG. 16 is a diagram for explaining a modification example of a method for manufacturing a semiconductor device according to the second embodiment. The local joint portion 50 may be continuously joined along the arrow C11 from the upper left corner of FIG. 16. By continuously joining, it may be joined in the linear region SL11.

[0064] <<Third Embodiment>> <Semiconductor Device 101> To explain the method for manufacturing a semiconductor device according to the third embodiment, a semiconductor device 101, which is an example of a semiconductor device manufactured by the method for manufacturing a semiconductor device according to the third embodiment, will be described.

[0065] FIG. 17 is a cross-sectional view of a semiconductor device 101, which is an example of a semiconductor device manufactured by the method for manufacturing a semiconductor device according to the third embodiment.

[0066] The semiconductor device 101 includes a semiconductor package 110, heat dissipation members 120 and 121, and joining members 130 and 131. Each component will be described.

[0067] [Semiconductor Package 110] The semiconductor package 110 includes heat dissipation layers 112 and 114, a semiconductor layer 115, and a sealing resin 116.

[0068] The semiconductor layer 115 includes, for example, an IGBT, a power MOSFET, or an FWD. Note that in FIGS. 17 to 20 and FIGS. 22 to 24, the detailed structure inside the semiconductor layer 115 is omitted and shown as one layer.

[0069] Each of the heat dissipation layers 112 and 114 dissipates heat from the semiconductor layer 115 to the outside of the semiconductor package 110. Each of the heat dissipation layers 112 and 114 is thermally connected to a semiconductor element inside the semiconductor layer 115. Heat generated by the semiconductor element inside the semiconductor layer 115 is transferred to each of the heat dissipation layers 112 and 114. Each of the heat dissipation layers 112 and 114 is formed of a conductive material. Each of the heat dissipation layers 112 and 114 is exposed to the outside from the encapsulating resin 116.

[0070] The encapsulating resin 116 encapsulates the semiconductor layer 115 to protect the semiconductor layer 115. The encapsulating resin 116 constitutes a part of the outer shape of the semiconductor package 110.

[0071] [Heat dissipation members 120 and 121] Each of the heat dissipation members 120 and 121 is a liquid-cooled cooler in which a coolant flows through a flow path formed inside.

[0072] [Bonding members 130 and 131] The bonding members 130 and 131 are, for example, plate solders. The bonding member 130 bonds the heat dissipation layer 112 and the heat dissipation member 120. The bonding member 131 bonds the heat dissipation layer 114 and the heat dissipation member 121.

[0073] <Method for manufacturing a semiconductor device according to the third embodiment> A method for manufacturing a semiconductor device according to the third embodiment will be described. FIGS. 18 to 24 are diagrams for explaining a method for manufacturing a semiconductor device according to the third embodiment.

[0074] First, the bonding member 130 is moved along the arrow D21 and placed on the surface 112S of the heat dissipation layer 112 of the semiconductor package 110 (FIGS. 18 and 19).

[0075] Regarding the semiconductor package 110 on which the joint member 130 is placed, from the surface 130S side of the joint member 130 opposite to the semiconductor package 110 side, the heat dissipation layer 112 and the joint member 130 are locally joined by the local joint portion 50 (FIGS. 20 and 21). The local joint portion 50 is, for example, a laser bonding machine or an ultrasonic bonding machine.

[0076] First, move the local joint portion 50 to the spot SP21. Then, the local joint portion 50 locally joins the heat dissipation layer 112 and the joint member 130 at the portion (spot SP21) where the local joint portion 50 is located.

[0077] Next, the local joint portion 50 is moved to the spot SP22 along the arrow B21. Note that while the local joint portion 50 is being moved along the arrow B21, the local joint portion 50 does not join the heat dissipation layer 112 and the joint member 130.

[0078] Then, at the spot SP22, the local joint portion 50 locally joins the heat dissipation layer 112 and the joint member 130.

[0079] Similarly, the local joint portion 50 is moved to the spot SP23 along the arrow B22, and at the spot SP23, the local joint portion 50 locally joins the heat dissipation layer 112 and the joint member 130. Also, the local joint portion 50 is moved to the spot SP24 along the arrow B23, and at the spot SP24, the local joint portion 50 locally joins the heat dissipation layer 112 and the joint member 130.

[0080] By locally joining the heat dissipation layer 112 and the joint member 130 at the spots SP21, SP22, SP23, and SP24, the joint member 130 is temporarily joined to the heat dissipation layer 112.

[0081] Similarly, the joint member 131 is temporarily joined to the surface 114S of the heat dissipation layer 114.

[0082] Then, the semiconductor package 110 with the joining members 130 and 131 temporarily joined is assembled such that the joining member 130 contacts the heat dissipation member 120. Also, the semiconductor package 110 with the joining members 130 and 131 temporarily joined is assembled such that the joining member 131 contacts the heat dissipation member 121.

[0083] For example, as shown in FIG. 22, the semiconductor package 110 is inserted between the heat dissipation member 120 and the heat dissipation member 121 provided at a distance where the semiconductor package 110 can be inserted therebetween by moving the semiconductor package 110 along the arrow E1.

[0084] Also, for example, as shown in FIG. 23, with respect to the semiconductor package 110, the heat dissipation member 120 is moved along the arrow F1 and the heat dissipation member 121 is moved along the arrow F2.

[0085] When the semiconductor package 110, the heat dissipation member 120, and the heat dissipation member 121 are assembled and heated, the semiconductor package 110 is joined to the heat dissipation member 120 and the heat dissipation member 121 by the joining members 130 and 131 (FIG. 24).

[0086] In the method of manufacturing a semiconductor device according to the third embodiment, the joining members 130 and 131 are temporarily joined to the semiconductor package 110. Then, the semiconductor package 110, the heat dissipation member 120, and the heat dissipation member 121 are joined by the joining members 130 and 131. By temporarily joining the joining members 130 and 131 to the semiconductor package 110 and then joining the heat dissipation member 120 and the heat dissipation member 121, displacement of the joining members 130 and 131 can be prevented.

[0087] Note that when manufacturing the semiconductor device 101 according to the third embodiment, the molds 81z and 82z as shown in the reference example of FIG. 30 cannot be used. Therefore, when manufacturing the semiconductor device 101 according to the third embodiment, the method of manufacturing a semiconductor device according to the third embodiment is particularly useful.

[0088] Note that the semiconductor package 110 is an example of a semiconductor package having heat dissipation layers formed on both sides.

[0089] <Modification Example> When temporarily joining the joining members 130 and 131 to the heat dissipation layer 112 and the heat dissipation layer 114 respectively, it is not limited to joining at points such as the spots SP21, SP22, SP23, and SP24. For example, when temporarily joining, it may be temporarily joined linearly.

[0090] FIG. 25 is a diagram for explaining a modification of the manufacturing method of the semiconductor device according to the third embodiment. The local joining portion 50 may be continuously joined along the arrow C21 from the upper left corner of FIG. 25. By continuously joining, it may be joined in the linear region SL21.

[0091] <Influence of Joining by the Local Joining Portion 50> In the step of temporarily joining the joining member to the heat dissipation layer or the heat dissipation member, the influence when temporarily joining by the local joining portion 50 will be described. FIGS. 26 to 29 are diagrams for explaining the influence in the manufacturing method of the semiconductor device according to the present embodiment. Here, the case of joining the joining member 30 and the heat dissipation layer 16 will be described.

[0092] FIG. 26 is a cross-sectional view of the portion to be joined when a laser joining machine 51 is used as the local joining portion 50. When joining with the laser joining machine 51, a part of the joining member 30 and the heat dissipation layer 16 melts at the condensing spot of the laser. The melted joining member 30 and heat dissipation layer 16 form an alloy layer 60 which is a layer of an alloy of the materials constituting the joining member 30 and the heat dissipation layer 16 respectively. For example, when a tin-based solder is used as the joining member 30 and copper is used as the heat dissipation layer 16, an alloy of tin and copper is formed as the alloy layer 60.

[0093] FIG. 27 is a cross-sectional view of a portion to be joined when an ultrasonic bonding machine 52 is used as the local joint 50. When joining with the ultrasonic bonding machine 52, indentations 35 are formed in the joining member 30. Further, the vicinity of the joined portion of the heat dissipation layer 16 sinks, and a refined crystal layer 16a with refined crystal grains is formed. For example, when copper is used as the heat dissipation layer 16, a refined crystal layer 16a with refined copper crystal grains is formed at the joined portion of the heat dissipation layer 16.

[0094] When joining using the laser bonding machine 51, an alloy layer 60 is formed. Also, when using the ultrasonic bonding machine 52, a refined crystal layer 16a is formed. When the joining member 30 is removed from the semiconductor device 1 and the heat dissipation member 20 is removed, an alloy layer 60 or a refined crystal layer 16a remains on the heat dissipation layer 16.

[0095] For example, as shown in FIG. 8, when temporarily joining in a dot pattern, as shown in FIG. 28, dot-shaped temporary joining marks TR1, TR2, TR3, and TR4 are formed on the surface 16S of the heat dissipation layer 16. Also, as shown in FIG. 10, when temporarily joining in a linear pattern, as shown in FIG. 29, a linear temporary joining mark TR5 is formed on the surface 16S of the heat dissipation layer 16.

[0096] It should be considered that all the embodiments disclosed this time are illustrative in all respects and not restrictive. The above embodiments may be omitted, substituted, or changed in various forms without departing from the scope and gist of the appended claims.

Explanation of Reference Numerals

[0097] 1, 101 Semiconductor device 10 Insulating substrate 12 Insulator layer 14 Wiring layer 16 Heat dissipation layer 16a Refined crystal layer 16S Surface 20 Heat dissipation member 30 Joining member 35 Indentation 50 Local joint 51 Laser bonding machine 52 Ultrasonic bonding machine 60 Alloy layer 110 Semiconductor package 112, 114 Heat dissipation layer 115 Semiconductor layer 116 Encapsulating resin 120, 121 Heat dissipation member 130, 131 Bonding member TR1, TR2, TR3, TR4, TR5 Temporary bonding marks

Claims

1. A method for manufacturing a semiconductor device, comprising: a semiconductor package having a heat dissipation layer formed on one or both sides; a heat dissipation member joined to the heat dissipation layer; and a joining member for joining the heat dissipation layer and the heat dissipation member, the method including a step of locally joining the joining member to only one of the heat dissipation layer or the heat dissipation member. A method for manufacturing a semiconductor device.

2. In the step of locally joining, a portion where the heat dissipation layer or the heat dissipation member and the joining member are joined is joined by a laser. The method for manufacturing a semiconductor device according to Claim 1.

3. In the step of locally joining, a portion where the heat dissipation layer or the heat dissipation member and the joining member are joined is joined by ultrasonic vibration. The method for manufacturing a semiconductor device according to Claim 1.

4. In the step of locally joining, the joining member is locally joined to the heat dissipation layer or the heat dissipation member at one or more locations. The method for manufacturing a semiconductor device according to any one of Claims 1 to 3.

5. In the step of locally joining, the joining member is continuously joined to the heat dissipation layer or the heat dissipation member so as to border the outer periphery of the joining member. The method for manufacturing a semiconductor device according to any one of Claims 1 to 3.

6. A semiconductor device, comprising: a semiconductor package having a heat dissipation layer formed on one or both sides; a heat dissipation member joined to the heat dissipation layer; a joining member for joining the heat dissipation layer and the heat dissipation member, wherein only one of the heat dissipation layer or the heat dissipation member has, on the side where the joining member is joined, one or more local alloy layers of the heat dissipation layer and the joining member or fine crystal layers of the heat dissipation layer. A semiconductor device.

7. A semiconductor package having a heat dissipation layer formed on one or both sides; a heat dissipation member joined to the heat dissipation layer; a joining member for joining the heat dissipation layer and the heat dissipation member, wherein only one of the heat dissipation layer or the heat dissipation member has, on the side where the joining member is joined, an alloy layer of the heat dissipation layer and the joining member or a fine crystal layer of the heat dissipation layer continuously bordering the outer periphery of the joining member. A semiconductor device.

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