Semiconductor Devices

Abstract

To obtain a semiconductor device capable of dealing with a large current and being miniaturized.SOLUTION: A semiconductor device 10 comprises: an insulation substrate 12; a first conductor part 14 and a second conductor part 16 which are formed on the insulation substrate 12; a semiconductor element 20 arranged on the first conductor part 14; a flat first terminal 30 connected with a source electrode of the semiconductor element 20; a flat second terminal 40 connected with the first conductor part 14; a connection member 50 electrically connecting a gate electrode of the semiconductor element 20 and the second conductor part 16; a flat support member 52 arranged at a predetermined interval from the second conductor part 16; a bar-like pin terminal 56 supported while being inserted in the support member 52, and connected with the second conductor part 16; and an encapsulation resin that encapsulates the insulation substrate 12, the first conductor part 14, the second conductor part 16, the semiconductor element 20, the connection member 50, and the support member 52.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a semiconductor device. [Background technology]

[0002] The semiconductor device disclosed in Patent Document 1 below includes a substrate on which a semiconductor chip is mounted, pin terminals connected to wiring patterns on the substrate, and a lead frame that supports the pin terminals and electrically connects electrodes of the semiconductor chip to the pin terminals. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6850938 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned prior art, in order to allow a large current to flow, it is necessary to increase the thickness of the lead frame that supports the pin terminals and electrically connects the electrodes of the semiconductor chip to the pin terminals. However, increasing the thickness of the lead frame makes it difficult to finely process the lead frame, which makes it difficult to stably press-fit (support) the pin terminals, and also leads to an increase in the size of the semiconductor device as the lead frame increases in size.

[0005] SUMMARY OF THE INVENTION In consideration of the above problems, an object of the present invention is to provide a semiconductor device that can handle a large current and can be miniaturized. [Means for solving the problem]

[0006] The semiconductor device of the present invention comprises an insulating substrate, a first conductor portion and a second conductor portion formed on the insulating substrate, a semiconductor element arranged on the first conductor portion, a flat first terminal connected to a first electrode of the semiconductor element, a flat second terminal connected to the first conductor portion, a connecting member electrically connecting a control electrode of the semiconductor element and the second conductor portion, a flat support member arranged at a predetermined distance from the second conductor portion, a rod-shaped pin terminal supported in a state inserted into the support member and connected to the second conductor portion, and a sealing resin that seals the insulating substrate, the first conductor portion, the second conductor portion, the semiconductor element, the connecting member, and the support member. [Effects of the Invention]

[0007] According to the present invention, a first conductor portion and a second conductor portion are formed on an insulating substrate, and a semiconductor element is disposed on the first conductor portion. A flat-plate-shaped first terminal is connected to a first electrode of the semiconductor element, and a flat-plate-shaped second terminal is connected to the first conductor portion. The control electrode of the semiconductor element and the second conductor portion are electrically connected by a connecting member. A flat-plate-shaped support member is disposed at a predetermined distance from the second conductor portion, and a rod-shaped pin terminal connected to the second conductor portion is inserted and supported by the support member. The insulating substrate, the first conductor portion, the second conductor portion, the semiconductor element, the connecting member, and the support member are encapsulated with a sealing resin. In this invention, the first terminal and the second terminal and the support member supporting the pin terminal are separate members. This allows the first terminal and the second terminal and the support member to be manufactured using flat plate materials with different thicknesses. Therefore, even if the thicknesses of the first terminal and the second terminal are increased to accommodate a large current, the thickness of the support member can be reduced, thereby preventing the semiconductor device from becoming larger and enabling it to be miniaturized. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view showing a semiconductor device according to an embodiment; [Figure 2] 1 is a perspective view showing a semiconductor device according to an embodiment in which the sealing resin is not shown; [Figure 3] 1 is a plan view showing a state in which the sealing resin is omitted in the semiconductor device according to the embodiment; [Figure 4] FIG. 2 is a plan view showing the configuration of an insulating substrate and its peripheral members. [Figure 5] FIG. 2 is a plan view showing an insulating substrate. [Figure 6] FIG. 2 is a perspective view showing a first terminal. [Figure 7] FIG. 4 is a perspective view showing a second terminal. [Figure 8] FIG. [Figure 9] FIG. 3 is a cross-sectional view showing a female thread member. [Figure 10] 3 is a perspective view showing the configuration of a bent portion and a tip connection portion of a first terminal and their peripheral members. FIG. [Figure 11] 11 is a perspective view corresponding to FIG. 10, showing a state in which the tip connection portion and the third conductor portion of the insulating substrate are joined with a conductive joining material. FIG. [Figure 12] 3 is a perspective view showing a bent portion and a tip connection portion of the first terminal. FIG. [Figure 13] FIG. [Figure 14] FIG. 2 is a perspective view showing the configuration of a connection member and its peripheral members. [Figure 15] 10 is a plan view showing a state in which a pin terminal is press-fitted into a through hole of a support member. FIG. [Figure 16] FIG. [Figure 17] FIG. 2 is a side view showing a pin terminal, a support member, and a part of an insulating substrate. [Figure 18] 1 is a first plan view showing a state during the manufacturing of a semiconductor device according to an embodiment. [Figure 19] FIG. 2 is a second plan view showing a state during the manufacturing of the semiconductor device according to the embodiment. [Figure 20] FIG. 10 is a third plan view showing a state during the manufacturing of the semiconductor device according to the embodiment. [Figure 21] FIG. 10 is a perspective view showing a first modified example of the second terminal. [Figure 22]FIG. 10 is a perspective view showing a second modified example of the second terminal. [Figure 23] FIG. 10 is a perspective view showing a first modified example of the connecting member. [Figure 24] FIG. 10 is a perspective view showing a second modified example of the connecting member. [Figure 25] FIG. 10 is a perspective view showing a first modified example of a pin terminal. [Figure 26] FIG. 10 is a plan view showing a state in which the pin terminal in the first modified example is inserted into the support member. [Figure 27] FIG. 10 is a perspective view showing a second modified example of the pin terminal. [Figure 28] FIG. 10 is a plan view showing a state in which the pin terminal in the second modified example is inserted into the support member. [Figure 29] FIG. 10 is a perspective view showing a third modified example of the pin terminal. [Figure 30] FIG. 11 is a side view showing a state in which the pin terminal in the third modified example is inserted into the support member. DETAILED DESCRIPTION OF THE INVENTION

[0009] A semiconductor device 10 according to one embodiment of the present invention will be described below with reference to Figures 1 to 30. In this embodiment, for convenience of explanation, the directions indicated by front-to-back, left-to-right, and up-to-down arrows appropriately shown in each figure are defined as the front-to-back direction, left-to-right direction, and up-to-down direction, and the positions and orientations of the components will be described. Also, in each figure, some reference numerals may be omitted to make the drawings easier to understand.

[0010] 1, the semiconductor device 10 according to this embodiment has a generally rectangular parallelepiped shape that is long in the front-rear direction and flat in the up-down direction. As shown in FIGS. 1 to 5, the semiconductor device 10 includes an insulating substrate 12, a first conductor 14, a second conductor 16, and a third conductor 18 formed on the insulating substrate 12, a semiconductor element 20 disposed on the first conductor 14, a flat first terminal 30 connected to a source electrode (first electrode) 22 of the semiconductor element 20, a flat second terminal 40 connected to the first conductor 14, and a gate electrode (control electrode) 24 of the semiconductor element 20 electrically connected to the second conductor 16. The semiconductor device comprises a connecting member 50, two flat support members 52 arranged at a predetermined distance from the second conductor portion 16 and the third conductor portion 18, two rod-shaped pin terminals 56 supported by being inserted into the two support members 52 and connected to the second conductor portion 16 and the third conductor portion 18, respectively, and a sealing resin 60 that seals the insulating substrate 12, the first conductor portion 14, the second conductor portion 16, the third conductor portion 18, the semiconductor element 20, the connecting member 50, and the two support members 52.

[0011] The insulating substrate 12 is a DCB (Direct Copper Bonding) ceramic substrate with a heat dissipation metal plate formed on its lower surface (rear surface). The insulating substrate 12 may be a printed circuit board or the like. The insulating substrate 12 is formed in the shape of a rectangular flat plate and is disposed in the center of the semiconductor device 10 in the front-rear direction, with the up-down direction of the semiconductor device 10 being the plate thickness direction. A first conductor 14, a second conductor 16, and a third conductor 18 are formed as conductor patterns (copper patterns in this case) on the upper surface (front surface) of the insulating substrate 12. The first conductor 14 is formed in the center of the insulating substrate 12, and the second conductor 16 and the third conductor 18 are formed on the left and right edges of the insulating substrate 12. The first conductor 14, the second conductor 16, and the third conductor 18 are insulated from each other.

[0012] 4 and 5, a semiconductor element 20 is disposed on the first conductor portion 14. The semiconductor element 20 is a power MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor). The semiconductor element 20 has a drain electrode (not shown) which is a second electrode formed on one surface (the surface (lower surface) on the insulating substrate 12 side), a source electrode 22 which is a first electrode formed on the other surface (the surface (upper surface) opposite to the insulating substrate 12), and a gate electrode 24 which is a control electrode.

[0013] The drain electrode of the semiconductor element 20 is joined to the first conductor portion 14 via a conductive adhesive. A conductive plate 26 (see FIG. 4) made of a conductive flat plate material (here, a copper plate) is disposed above the source electrode 22 of the semiconductor element 20. The conductive plate 26 is joined to the source electrode 22 via a conductive adhesive. In this embodiment, solder is used as the conductive adhesive. The solder may be lead-free solder. The conductive adhesive is not limited to solder, and may be an alloy or metal having conductivity and adhesiveness, or a conductive adhesive containing silver paste or silver nanoparticles.

[0014] As shown in FIGS. 1 to 3 and 6, the first terminal 30 is configured in a flat plate shape and is disposed at the front of the semiconductor device 10. The first terminal 30 corresponds to a "terminal member." The first terminal 30 is manufactured by press-forming a conductive flat plate material (here, a copper plate). The first terminal 30 integrally includes an inner terminal portion 30A disposed inside the sealing resin 60 (see FIG. 1) and an outer terminal portion 30B disposed in an exposed state outside the sealing resin 60.

[0015] The outer terminal portion 30B has a generally rectangular flat plate shape with its thickness direction aligned with the vertical direction of the semiconductor device 10. The inner terminal portion 30A has a hanging portion 30A1 extending downward from the rear end of the outer terminal portion 30B and a joint portion 30A2 extending rearward from the rear end of the hanging portion 30A1. The joint portion 30A2 is disposed above the conductive plate 26 and is joined to the conductive plate 26 via solder, which is a conductive joining material. This electrically connects the first terminal 30 to the source electrode 22 via the conductive plate 26 and the solder.

[0016] 1 to 3 and 7, the second terminal 40 is configured in a flat plate shape and is disposed at the rear of the semiconductor device 10. The second terminal 40 is manufactured by press-forming a conductive flat plate material (here, a copper plate). The second terminal 40 integrally includes an inner terminal portion 40A disposed inside the sealing resin 60 (see FIG. 1) and an outer terminal portion 40B disposed outside the sealing resin 60 in an exposed state.

[0017] The outer terminal portion 40B has a generally rectangular flat plate shape with its thickness direction aligned with the vertical direction of the semiconductor device 10. The inner terminal portion 40A extends downward from the front end of the outer terminal portion 40B. A joint portion 40A1 that is bent forward is formed at the lower end of the inner terminal portion 40A. The joint portion 40A1 is joined to the rear end side of the first conductor portion 14 on the insulating substrate 12 via a conductive bonding material. This electrically connects the second terminal 40 to the drain electrode of the semiconductor element 20 via the conductive bonding material and the first conductor portion 14.

[0018] Circular insertion holes 36, 42 are formed in the center of the outer terminal portion 30B of the first terminal 30 and the center of the outer terminal portion 40B of the second terminal 40, respectively, penetrating the outer terminal portions 30B, 40B in the plate thickness direction. A female screw member 46 (see FIGS. 8 and 9) is inserted into and fixed to each of these insertion holes 36, 42. The female screw member 46 is a bag-shaped female screw nut and has a bottomed cylindrical shape that opens upward. A female screw portion 48 is formed on the inner periphery of the female screw member 46.

[0019] An end (one end) of the female screw member 46 on the opening side is inserted (here, press-fitted) into each insertion hole 36, 42 of the outer terminal portion 30B, 40B. A brim-shaped flange portion 46A is formed on the outer peripheral surface of the opening side of the female screw member 46, and this flange portion 46A abuts against the lower surface of the outer terminal portion 30B, 40B. The other end side of the female screw member 46 is sealed in the sealing resin 60. Note that the configuration is not limited to one in which one end of the female screw member 46 is press-fitted into the insertion hole 36, 42 and fixed to the first terminal 30 and the second terminal 40, but may be one in which it is fixed to the first terminal 30 and the second terminal 40 by means of adhesive or the like. Furthermore, the configuration is not limited to one in which the female screw member 46 is fixed to the first terminal 30 and the second terminal 40. For example, a cylindrical raised portion may be formed by burring the outer terminal portion 30B, 40B, and the female screw portion 48 may be formed on the inner periphery of the raised portion.

[0020] The female screw member 46 is fixed to the first terminal 30 and the second terminal 40, thereby providing female screw portions in the first terminal 30 and the second terminal 40. This allows a crimp terminal, a bus bar, or the like attached to external wiring to be connected to the first terminal 30 and the second terminal 40 by screw fastening.

[0021] 1, the front end of the outer terminal portion 30B of the first terminal 30 forms a protrusion 30B1 that protrudes forward from the front end of the sealing resin 60. The rear end of the outer terminal portion 40B of the second terminal 40 forms a protrusion 40B1 that protrudes rearward from the rear end of the sealing resin 60. By utilizing these protrusions 30B1, 40B1, the top surfaces (surfaces on which the female threads are provided) of the outer terminal portions 30B, 40B can be formed as exposed surfaces by bringing the top surfaces (surfaces on which the female threads are provided) of the outer terminal portions 30B, 40B into contact with a molding die (upper die) for molding the sealing resin 60, and pressing the protrusions 30B1, 40B1 from the opposite side with a molding die (lower die) to bring them into close contact with the upper die.

[0022] Notches 38, 44 that are open on the left and right sides of the front end of the outer terminal portion 30B and the rear end of the outer terminal portion 40B are formed, respectively. These notches 38, 44 function to position the first terminals 30 and the second terminals 40. Furthermore, the sealing resin 60 is allowed to enter these notches 38, 44, thereby improving the strength against the load applied when the first terminals 30 and the second terminals 40 are fastened with screws. Note that a configuration in which through holes are formed instead of the notches 38, 44 may also be used.

[0023] 6, 10, and 11, a grounding extension 39 extends leftward from the left end of the rear end of the inner terminal portion 30A of the first terminal 30. The tip of the grounding extension 39 is disposed above the third conductor 18. A bent portion 39A is formed at the tip of the grounding extension 39, bending toward the third conductor 18 (i.e., toward the insulating substrate 12; downward). This bent portion 39A is bent around a curvature center line CC (see FIG. 12) along the front-rear direction.

[0024] A tip connection portion 39B, which is connected to the third conductor portion 18, is provided at the tip (lower end) of the bent portion 39A. The tip connection portion 39B is formed in an arc shape that convexes downward when viewed from the left-right direction, and has a curved lower surface. The curved surface of this tip connection portion 39B is in line contact with the third conductor portion 18, which is the connection target portion. As shown in FIG. 11 , this tip connection portion 39B is joined to the third conductor portion 18 by solder BM, which is a conductive bonding material. In the first terminal 30 configured as described above, the curved shape of the tip connection portion 39B is formed when the flat plate material that constitutes the first terminal 30 is punched by press working. Then, the bent portion 39A is formed by a subsequent bending process.

[0025] The portion of the tip connection portion 39B that makes line contact with the third conductor portion 18 (see the two-dot chain line LC in FIG. 12) extends in a direction perpendicular to the center line of curvature CC. The tip connection portion 39B is not limited to a configuration in which it makes line contact with the connection target portion, and may be configured to make point contact or surface contact. The tip connection portion 39B is not limited to a configuration in which it makes direct contact with the third conductor portion 18 (connection target portion), and may be configured such that a conductive bonding material is interposed between the tip connection portion 39B and the connection target portion, and the tip connection portion 39B and the connection target portion are connected via the conductive bonding material. The connection target portion is not limited to a conductor portion on the insulating substrate 12, and may be an electrode of a semiconductor element, or the like.

[0026] As shown in Fig. 4, a connection member 50 is disposed on the insulating substrate 12. The connection member 50 electrically connects the gate electrode 24 of the semiconductor element 20 and the second conductor portion 16. As shown in Figs. 13 and 14, the connection member 50 is manufactured by press-forming a conductive flat plate material (here, a copper plate) and is formed in an elongated shape. The flat plate material constituting the connection member 50 is set to have a smaller plate thickness than the flat plate materials constituting the first terminal 30 and the second terminal 40.

[0027] The longitudinal center of the connecting member 50 is a long, plate-like horizontal portion 50A extending parallel to the insulating substrate 12. A conductor connection portion 50B extends obliquely from one longitudinal end of the horizontal portion 50A toward one longitudinal side and downward of the horizontal portion 50A (the insulating substrate 12 side). The tip of the conductor connection portion 50B is bent to be approximately parallel to the insulating substrate 12 and is disposed on the second conductor portion 16. The tip of the conductor connection portion 50B is joined to the second conductor portion 16 by solder BM (see FIG. 14 ), which is a conductive bonding material. A gate connection portion 50C extends obliquely from the other longitudinal end of the horizontal portion 50A toward the other longitudinal side and downward of the horizontal portion 50A (the insulating substrate 12 side). The gate connection portion 50C is formed to be narrower than the horizontal portion 50A and the conductor connection portion 50B. The tip of the gate connection portion 50C is curved upward in an arc shape and is placed on the gate electrode 24. The tip of the gate connection portion 50C is joined to the gate electrode 24 by solder BM (see FIG. 14), which is a conductive bonding material.

[0028] As shown in FIGS. 2 to 4 , flat support members 52 are disposed above the left side of the front end portion of the insulating substrate 12 and above the right side of the rear end portion thereof. One support member 52 is disposed above the second conductor portion 16 at a predetermined distance, and the other support member 52 is disposed above the third conductor portion 18 at a predetermined distance. These support members 52 are manufactured by press-forming a conductive flat plate material (copper plate in this case) and are formed into a substantially rectangular flat plate shape. These support members 52 are disposed parallel to the insulating substrate 12. The flat plate material constituting these support members 52 is set to have a thickness thinner than the flat plate material constituting the first terminal 30 and the second terminal 40, but thicker than the flat plate material constituting the connecting member 50.

[0029] As shown in FIG. 15 , a polygonal (here, substantially rectangular) through-hole 54 is formed in the center of support member 52. The inner circumferential surfaces of the four corners of this through-hole 54 are curved, forming an arc shape when viewed from the top-bottom direction, which is the penetration direction of through-hole 54. A pin terminal 56 is inserted (press-fitted) into this through-hole 54 and supported therein. As shown in FIG. 16 , pin terminal 56 is formed in a long rod shape (here, cylindrical) from a conductive material (here, metal). Note that the shape of through-hole 54 in support member 52 is not limited to the above and can be modified as appropriate. That is, through-hole 54 may have any polygonal shape, such as a triangular, pentagonal, or hexagonal shape. In addition, in this embodiment, the inner surfaces of the four corners of the through hole 54 are formed into a curved shape to alleviate stress concentration at the four corners due to the press-fitting of the pin terminal 56, but the inner surfaces of the corners of the through hole 54 may be configured not to be formed into a curved shape.

[0030] A brim-shaped flange portion 56A is formed on one longitudinal end (lower end) of the pin terminal 56. The longitudinal end of the pin terminal 56 is inserted (press-fitted) into the through hole 54 of the support member 52 from above, i.e., from the side opposite the second conductor portion 16 or the third conductor portion 18 of the insulating substrate 12. As a result, four points on the outer peripheral surface of the lower end of the pin terminal 56 are in line contact with the inner peripheral surface of the through hole 54. The lower surface of the flange portion 56A of the pin terminal 56 forms an opposing surface 57 that faces the edge of the through hole 54 from above, and is joined to the upper surface of the support member 52 via solder BM, which is a conductive bonding material. The term "facing" as used above includes cases where the flange portion 56A is in contact with the edge of the through hole 54, as well as cases where the flange portion 56A is connected to the edge of the through hole 54 via the solder BM.

[0031] 15, solder BM (not shown in FIG. 4) is filled between the outer periphery of the pin terminal 56 and the inner periphery of the through hole 54. Regarding this filling, in this embodiment, after the pin terminal 56 is press-fitted into the through hole 54 of the support member 52, the support member 52 and the pin terminal 56 are heated, and the layer of solder BM provided on the upper surface of the support member 52 is melted. The melted solder BM wets and spreads between the upper surface of the support member 52 and the opposing surface 57 of the flange portion 56A, and is poured by the flange portion 56A into the gap between the outer periphery of the pin terminal 56 and the inner periphery of the through hole 54, and then solidifies. This increases the contact area between the pin terminal 56 and the support member 52 via the solder BM.

[0032] 17 , the lower end of the pin terminal 56 abuts against the upper surface of the second conductor portion 16 or the third conductor portion 18 of the insulating substrate 12, and is joined to the second conductor portion 16 or the third conductor portion 18 by solder BM. This electrically connects the pin terminal 56 to the second conductor portion 16 or the third conductor portion 18. The pin terminal 56 connected to the second conductor portion 16 is used for inputting a control signal to the gate electrode 24. The pin terminal 56 connected to the third conductor portion 18 is used for grounding, and the source electrode 22 is grounded via the first terminal 30, the third conductor portion 18, and the pin terminal 56.

[0033] 1, in the semiconductor device 10 having the above configuration, the insulating substrate 12, the first conductor portion 14, the second conductor portion 16, the third conductor portion 18, the semiconductor element 20, the connecting member 50, the support member 52, and the lower end portions (base end portions) of the pin terminals 56 are sealed with sealing resin 60. The outer terminal portions 30B of the first terminals 30 and the second terminals 40 are provided on the upper surface of the sealing resin 60 and exposed to the outside of the sealing resin 60. The upper end portions (other longitudinal end portions; tip end portions) of the pin terminals 56 are provided so as to protrude outside the sealing resin 60.

[0034] As shown in Figures 2 to 5, in addition to the first to third conductors 14, 16, and 18, two suspension member joints 19 made of a conductor pattern (copper pattern) are provided on the insulating substrate 12. The two suspension member joints 19 are formed on the right side of the front end side and the left side of the rear end side of the insulating substrate 12. Suspension pins 62, which are suspension members, are joined to each of these suspension member joints 19 using a conductive adhesive material. The suspension pins 62 are made of a plate material with the same thickness as the support member 52, and are elongated in the left-right direction.

[0035] The hanger pins 62 and support members 52 are part of the lead frame LF shown in FIGS. 18 and 19. That is, during the manufacture of the semiconductor device 10, as shown in FIG. 18, the insulating substrate 12 to which the first terminals 30, the second terminals 40, the connecting members 50, and the pin terminals 56 are bonded is supported by the lead frame LF via the pin terminals 56. In the state shown in FIG. 18, the four support members 52 and the two hanger pins 62 are each connected to the lead frame LF. The semiconductor device 10 is transported in this state to the next process. In the next process, as shown in FIG. 19, the two support members 52 are cut from the lead frame LF, but the two hanger pins 62 remain connected to the lead frame LF. The semiconductor device 10 is transported in this state to the next process. In the next process, as shown in FIG. 20, the sealing resin 60 is molded. After the sealing resin 60 is molded, the two hanger pins 62 are cut from the lead frame LF, completing the semiconductor device 10 shown in FIG. 1. In the semiconductor device 10 thus manufactured, the end faces of the support pins 62 are exposed to the outside of the sealing resin 60 (see FIG. 1).

[0036] Next, the operation and effects of this embodiment will be described. In the semiconductor device 10 configured as described above, a first conductor 14 and a second conductor 16 are formed on an insulating substrate 12, and a semiconductor element 20 is disposed on the first conductor 14. The drain electrode of the semiconductor element 20 is connected to the first conductor 14. A flat-plate-shaped first terminal 30 is connected to a source electrode 22 of the semiconductor element 20, and a flat-plate-shaped second terminal 40 is connected to the first conductor 14. The gate electrode 24 of the semiconductor element 20 and the second conductor 16 are electrically connected by a connecting member 50. A flat-plate-shaped supporting member 52 is disposed at a predetermined distance from the second conductor 16, and a rod-shaped pin terminal 56 connected to the second conductor 16 is inserted and supported by the supporting member 52. The insulating substrate 12, the first conductor 14, the second conductor 16, the semiconductor element 20, the connecting member 50, and the supporting member 52 are sealed with a sealing resin 60.

[0037] The first terminals 30 and the second terminals 40 and the support member 52 supporting the pin terminals 56 are separate members. This allows the first terminals 30 and the second terminals 40 and the support member 52 to be manufactured from flat plate materials with different thicknesses. Therefore, even if the thicknesses of the first terminals 30 and the second terminals 40 are increased to accommodate a large current, the thickness of the support member 52 can be reduced, thereby preventing the overall configuration of the semiconductor device 10 from becoming larger and enabling the semiconductor device 10 to be miniaturized. Furthermore, since there is no need to increase the thickness of the lead frame LF from which the support member 52 is made, the difficulty of fine processing of the lead frame LF that would otherwise be required due to an increase in thickness can be avoided. As a result, for example, the through holes 54 in the support member 52 can be formed with high precision, allowing the pin terminals 56 to be press-fitted into the through holes 54 with high precision and supported.

[0038] The first terminal 30 and the second terminal 40 each have an inner terminal portion 30A, 40A disposed inside the sealing resin 60 and an outer terminal portion 30B, 40B disposed in an exposed state outside the sealing resin 60. The outer terminal portions 30B, 40B of the first terminal 30 and the second terminal 40 are each provided with a female thread portion 48, allowing connection to the first terminal 30 and the second terminal 40 by screw fastening. Furthermore, since there is no need to embed a screw fastening nut in the sealing resin 60, the semiconductor device 10 can be made thinner. As a result, for example, the heat dissipation performance of the semiconductor device 10 can be improved. Furthermore, for example, compared to a configuration in which the first terminal and the second terminal are extended and the screw fastening nut is held in the sealing resin 60 using the extended portion, wiring resistance can be reduced, allowing for low inductance.

[0039] The outer terminal portions 30B, 40B each have an insertion hole 36, 42 penetrating in the plate thickness direction, and the female thread portion 48 is formed in a female thread member 46 that is inserted into and fixed in the insertion hole 36, 42 of the outer terminal portion 30B, 40B. This makes it possible to increase the strength of the female thread portion 48 compared to, for example, a configuration in which the outer terminal portion 30B, 40B is subjected to burring to form a cylindrical rising portion and the female thread portion 48 is formed on the inner periphery of the rising portion.

[0040] One end of the female screw member 46 is inserted into the insertion holes 36, 42, and the other end is sealed in the sealing resin 60. This fixes the female screw member 46 to the sealing resin 60, improving the strength against the load applied when the first terminal 30 and the second terminal 40 are fastened with the screws.

[0041] Furthermore, notches 38, 44 that are open on the left and right sides of the front end of the outer terminal portion 30B and the rear end of the outer terminal portion 40B are formed, respectively. Sealing resin 60 fills these notches 38, 44. This further improves the strength against the load applied when the first terminal 30 and the second terminal 40 are fastened with screws.

[0042] The first terminal 30 also has a bent portion 39A bent toward the third conductor 18 and a tip connection portion 39B provided at the tip of the bent portion 39A. This tip connection portion 39B is connected to the third conductor 18 by solder BM. The shape of this tip connection portion 39B is formed when the flat plate material constituting the first terminal 30 is punched by press working, so the shape of the tip connection portion 39B can be stabilized regardless of the plate thickness of the flat plate material or the bending radius of the bent portion 39A. As a result, the bonding strength between the tip connection portion 39B and the third conductor 18 via the solder BM can be stabilized.

[0043] The tip connection portion 39B is formed in a curved shape and is in line contact with the third conductor 18. This facilitates stable formation of a fillet of the solder BM. Furthermore, since the thickness of the solder is easily ensured at the outermost periphery of the tip connection portion 39B, where stress due to thermal contraction of the solder BM tends to concentrate, stress can be alleviated. Furthermore, since the tip connection portion 39B provided at the tip of the bent portion 39A is joined to the third conductor 18 as described above, the area required for joining can be kept constant regardless of the thickness of the flat plate material or the bending radius of the bent portion 39A. This prevents the area occupied by the first terminal 30 from becoming large, thereby avoiding an increase in product size.

[0044] It is also possible to bend the portion of the grounding extension 39 of the first terminal 30 that is distal to the bent portion 39A so that it is parallel to the insulating substrate 12, and connect the bent portion to the third conductor portion 18 (the connection target portion). However, in such a configuration, as the thickness of the first terminal 30 (terminal member) increases, the bend radius of the bent portion increases. As a result, it becomes difficult to form a constant bend radius of the bent portion, which causes a problem of making it difficult to stably form a solder fillet. Furthermore, since a large area is required to join the bent portion to the connection target portion, the overall configuration of the semiconductor device 10 becomes large. In this regard, the present embodiment can solve the above-mentioned problems.

[0045] Furthermore, the point LC (see FIG. 12) of line contact between the tip connection portion 39B and the third conductor 18 extends in a direction perpendicular to the curvature center line CC, which is the bending center of the bent portion 39A. Because of this configuration, the tip connection portion 39B can be formed by punching the flat plate material that constitutes the first terminal 30 using a press process, and then the bent portion 39A can be bent using a bending process, thereby forming the tip connection portion 39B and the bent portion 39A with fewer steps. This can reduce the manufacturing cost of the first terminal 30, for example.

[0046] Furthermore, according to this embodiment, the semiconductor element 20 is disposed on the first conductor portion 14 of the insulating substrate 12, and a flat support member 52 is disposed at a predetermined distance from the second conductor portion 16 and the third conductor portion 18 of the insulating substrate 12. Cylindrical pin terminals 56 are inserted and supported in the support member 52, and the pin terminals 56 are connected to the second conductor portion 16 and the third conductor portion 18. The support member 52 has through holes 54 penetrating in the plate thickness direction, through which the pin terminals 56 are inserted. Because the through holes 54 are polygonal (here, rectangular), the contact area between the pin terminals 56 and the through holes 54 is smaller than when the through holes 54 are circular holes. Therefore, the pin terminals 56 can be inserted (press-fitted) into the through holes 54 with more stable accuracy and support than when the through holes 54 are circular holes.

[0047] The solder BM that joins the pin terminal 56 and the support member 52 fills the gap between the outer periphery of the pin terminal 56 and the inner periphery of the through hole 54. This increases the contact area between the pin terminal 56 and the support member 52 via the solder BM, thereby reducing the electrical resistance between the pin terminal 56 and the support member 52. Furthermore, the pin terminal 56 has an opposing surface 57 (see FIG. 16 ) that faces the edge of the through hole 54 from the side opposite the second conductor portion 16 or the third conductor portion 18, and this opposing surface 57 is joined to the edge of the through hole 54 by the solder BM. This also increases the contact area between the pin terminal 56 and the support member 52 via the solder BM, thereby further reducing the electrical resistance between the pin terminal 56 and the support member 52. The inner periphery of each of the four corners of the through hole 54 is curved. This reduces stress concentration at the four corners due to press-fitting of the pin terminal 56 into the through hole 54.

[0048] <Various modified examples> Next, various modified examples of the above embodiment will be described with reference to FIGS. 21 to 30. FIG. 21 shows a perspective view of a first modified example of the second terminal 40. The first modified example of the second terminal 40 corresponds to a "terminal member." In this first modified example of the second terminal 40, the inner terminal portion 40A has a bent portion 40A1 bent toward the first conductor portion 14 (connection target portion) of the insulating substrate 12, and a tip connection portion 40A2 provided at the tip portion (lower end) of the bent portion 40A1. The lower end of the tip connection portion 40A2 is substantially V-shaped. The lower end of the tip connection portion 40A2 is in line contact with the first conductor portion 14. When the tip connection portion 40A2 and the first conductor portion 14 are joined by soldering, a solder fillet is easily and stably formed.

[0049] 22 shows a perspective view of a second modified example of second terminal 40. The second modified example of second terminal 40 corresponds to a "terminal member" and, like the first modified example of second terminal 40, has a bent portion 40A1 and a tip connection portion 40A2. The lower end of tip connection portion 40A2 is wave-shaped and is in line contact with first conductor portion 14 of insulating substrate 12 at multiple locations. When tip connection portion 40A2 and first conductor portion 14 are joined by soldering, a stable solder fillet is easily formed.

[0050] FIG. 23 shows a perspective view of a first modified example of the connecting member 50. The first modified example of the connecting member 50 corresponds to a "terminal member." In this first modified example of the connecting member 50, the gate connecting portion 50C has a bent portion 50C1 bent toward the gate electrode 24 (connection target portion) of the semiconductor element 20, and a tip connecting portion 50C2 provided at the tip (lower end) of the bent portion 50C1. The lower end of the tip connecting portion 50C2 is substantially V-shaped and is in line contact with the gate electrode 24. When this tip connecting portion 50C2 and the gate electrode 24 are joined with solder, a solder fillet is likely to be formed stably.

[0051] FIG. 24 shows a perspective view of a second modified example of the connecting member 50. The second modified example of the connecting member 50 corresponds to a "terminal member" and, like the first modified example of the connecting member 50, has a bent portion 50C1 and a tip connection portion 50C2. In this second modified example of the connecting member 50, the conductor connection portion 50B has a bent portion 50B1 bent toward the second conductor portion 16 of the insulating substrate 12 and a tip connection portion 50B2 provided at the tip portion (lower end) of the bent portion 50B1. The lower end of the tip connection portion 50B2 is wave-shaped and is in line contact with the second conductor portion 16 at multiple locations. When this tip connection portion 50B2 and the second conductor portion 16 are joined by soldering, a solder fillet is likely to be formed stably.

[0052] FIG. 25 shows a perspective view of a first modified pin terminal 56. The first modified pin terminal 56 does not have a flange portion 56A. As shown in FIG. 26, the support member 52 into which the first modified pin terminal 56 is inserted has a chamfered portion 55 formed on the upper surface of the edge of the through hole 54. After the pin terminal 56 is press-fitted into the through hole 54 of the support member 52, the support member 52 and the pin terminal 56 are heated to melt the solder layer provided on the upper surface of the support member 52. The molten solder is guided by the chamfered portion 55 and flows between the outer periphery of the pin terminal 56 and the inner periphery of the through hole 54, and then solidifies. This increases the contact area between the pin terminal 56 and the support member 52 via the solder BM.

[0053] FIG. 27 shows a perspective view of a second modified pin terminal 56. Like the first modified pin terminal 56, the second modified pin terminal 56 does not have a flange portion 56A, but has multiple (four in this example) grooves 56B on the outer periphery of the lower end portion. The four grooves 56B extend in the axial direction (vertical direction) of the pin terminal 56. As shown in FIG. 28, the pin terminal 56 is press-fitted into the through hole 52 of the support member 52 so that the four grooves 56B face the four corners of the through hole 54. After the pin terminal 56 is press-fitted into the through hole 54 of the support member 52, the support member 52 and the pin terminal 56 are heated to melt the solder layer on the upper surface of the support member 52. The molten solder is guided by the multiple grooves 56B, flows into the gap between the outer periphery of the pin terminal 56 and the inner periphery of the through hole 54, and then solidifies. Furthermore, the solder on the conductor portion of the insulating substrate 12 is sucked up by capillary action in the grooves 56B, flows into the gap between the outer periphery of the pin terminal 56 and the inner periphery of the through-hole 54, and then solidifies. This increases the contact area between the pin terminal 56 and the support member 52 via the solder BM.

[0054] FIG. 29 shows a perspective view of a third modified pin terminal 56. In the third modified pin terminal 56, the portion other than the lower end is a large-diameter portion 56L, and the lower end is a small-diameter portion 56S. The small-diameter portion 56S is formed to have a smaller diameter than the large-diameter portion 56L and is press-fitted into the through-hole 54 of the support member 52 (see FIG. 30). A downward-facing opposing surface 57 is formed between the small-diameter portion 56S and the large-diameter portion 56L, and this opposing surface 57 faces the edge of the through-hole 54 from above. When the pin terminal 56 and the support member 52 are heated and the layer of solder BM provided on the upper surface of the support member 52 melts, the molten solder BM wets and spreads between the upper surface of the support member 52 and the opposing surface 57, and is then poured by the opposing surface 57 into the gap between the outer periphery of the pin terminal 56 and the inner periphery of the through-hole 54, where it then solidifies. This increases the contact area between the pin terminals 56 and the support member 52 via the solder BM.

[0055] In the above embodiment, the semiconductor element 20 is a power MOSFET, but the present invention is not limited to this. The semiconductor element may be other elements such as an IGBT, a thyristor, or a diode. Furthermore, materials such as silicon, SiC, and GaN can be used as the material of the semiconductor element.

[0056] Furthermore, although the semiconductor element 20 in the above embodiment is a so-called vertical semiconductor element having a source electrode 22 on one side and a drain electrode on the other side, the present invention is not limited to this. The semiconductor element may also be a so-called horizontal semiconductor element having a source electrode and a drain electrode on one side.

[0057] In addition, the present invention can be implemented with various modifications within the scope of the gist thereof. Furthermore, it goes without saying that the scope of the rights of the present invention is not limited to the above-described embodiment. [Explanation of symbols]

[0058] 10 Semiconductor device 12 Insulating substrate 14 First conductor section 16 Second conductor section 20 Semiconductor elements 22 Source electrode (first electrode) 24 Gate electrode (control electrode) 30 1st terminal 40 2nd terminal 50 Connecting member 52 Support member 60 Sealing resin

Claims

1. an insulating substrate; a first conductor portion and a second conductor portion formed on the insulating substrate; a semiconductor element disposed on the first conductor portion; a first terminal having a flat plate shape connected to a first electrode of the semiconductor element; a second terminal having a flat plate shape connected to the first conductor portion; a connection member that electrically connects the control electrode of the semiconductor element and the second conductor portion; a flat support member disposed at a predetermined interval from the second conductor; a rod-shaped pin terminal supported in a state of being inserted through the support member and connected to the second conductor portion; a sealing resin that seals the insulating substrate, the first conductor portion, the second conductor portion, the semiconductor element, the connecting member, and the supporting member, The first terminal and the second terminal are spaced apart from the pin terminal.

2. The semiconductor device according to claim 1 , wherein the first terminal and the second terminal are formed of a member having a thickness greater than that of the support member.

Images