Semiconductor device

Abstract

To provide a semiconductor device in which the reliability of a source sense wire is improved.SOLUTION: A semiconductor substrate 100 includes a semiconductor substrate 111 having a first main electrode 112 on one surface and a second main electrode 114 and a first control electrode 113 on the other surface, a first conductive plate 120 disposed on one surface side of the semiconductor substrate and bonded to the first main electrode through a conductive bonding member, a second conductive plate 130 disposed on the other surface side of the semiconductor substrate and bonded to the second main electrode 114 through a conductive bonding member, a first control bonding wire 140 electrically connected to the first control electrode 113, and a second control bonding wire 141 to be bonded to the second conductive plate. The first control electrode and the first main electrode overlap with each other in a lamination direction. The second control bonding wire is bonded to a first bonding part 141a provided on a surface of the second conductive plate. The first bonding part does not overlap with the first main electrode in the lamination direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] Even in a semiconductor device with a double-sided cooling structure, if wires are bonded in a high-temperature region, concerns arise about the thermal reliability of the wires. Therefore, in order to ensure the thermal reliability of the wires, it is necessary to improve the wire configuration. For example, Patent Document 1 listed below discloses a semiconductor packaging structure in which multiple wire bonds are formed as the main current path. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-126066 Summary of the Invention [Problem to be solved by the invention]

[0004] In view of the configuration described in Patent Document 1, an object is to provide a semiconductor device that achieves improved reliability of source sense wires that do not normally have multiple wires. [Means for solving the problem]

[0005] A semiconductor device comprising: a semiconductor element having a first main electrode on one side and a second main electrode and a first control electrode on the other side; a first conductor plate arranged on the one side of the semiconductor element and joined to the first main electrode via a conductive bonding member; a second conductor plate arranged on the other side of the semiconductor element and joined to the second main electrode via the conductive bonding member; a first control bonding wire electrically connected to the first control electrode; and a second control bonding wire joined to the second conductor plate, wherein the first control electrode and the first main electrode overlap each other in the stacking direction, and the second control bonding wire is joined to a first bonding portion provided on the surface of the second conductor plate, and the first bonding portion does not overlap the first main electrode in the stacking direction. [Effects of the Invention]

[0006] A semiconductor device with improved reliability of the source sense wires can be provided. [Brief explanation of the drawings]

[0007] [Figure 1] 1A and 1B are a plan view and a cross-sectional view of a semiconductor device according to an embodiment of the present invention; [Figure 2] 1A and 1B are plan and cross-sectional views of a semiconductor chip according to an embodiment of the present invention; [Figure 3] First Modification [Figure 4] Second Modification [Figure 5] Third Modification [Figure 6] Fourth Modification [Figure 7] Fifth Modification [Figure 8] Sixth Modification [Figure 9] 1 is a diagram illustrating a double-sided cooling structure according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The following description and drawings are examples for explaining the present invention, and some omissions and simplifications have been made as appropriate for clarity of explanation. The present invention can be implemented in various other forms. Unless otherwise specified, each component may be singular or plural.

[0009] In order to facilitate understanding of the invention, the position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc. Therefore, the present invention is not necessarily limited to the position, size, shape, range, etc. disclosed in the drawings.

[0010] (One embodiment and overall configuration) (Fig. 1, Fig. 2) Fig. 1(a) is a plan view of the semiconductor device 100, Fig. 1(b) is a plan view of the semiconductor device 100 in which a second conductor plate 130 and a source sense wire 141 are illustrated in Fig. 1(a), and Fig. 1(c) is a cross-sectional view taken along line A-A' in Fig. 1(b). Also, Fig. 2(a) is a plan view of the semiconductor chip 110, and Fig. 2(b) is a cross-sectional view taken along line B-B' in Fig. 2(a).

[0011] The semiconductor device 100 has a semiconductor chip 110 (semiconductor element), a first conductor plate 120, a second conductor plate 130, a gate wire 140 (first control bonding wire), a source sense wire 141 (second control bonding wire), a gate conductor plate 150, and a source sense conductor plate 151. At least one semiconductor chip 110 is provided in the semiconductor device 100. When multiple semiconductor chips 110 are provided in the semiconductor device 100, the semiconductor chips 110 are at the same potential. The semiconductor chips 110 are electrically connected to each other by the gate conductor plate 150 and the gate wire 140.

[0012] The first conductor plate 120 is disposed so as to be electrically connected to one surface of the semiconductor chip 110 by a conductive bonding member (not shown). The second conductor plate 130 is disposed so as to be electrically connected to the other surface of the semiconductor chip 110 by a conductive bonding member (not shown). The second conductor plate 130 is also electrically connected to a source sense conductor plate 151 by a source sense wire 141. Note that the portion on the surface 131 of the second conductor plate 130 to which the source sense wire 141 is bonded is referred to as a first bonding portion 141a.

[0013] The semiconductor chip 110 has a semiconductor substrate 111. A first main electrode 112 is formed on one surface of the semiconductor substrate 111, and a second main electrode 114 and a first control electrode 113 are formed on the other surface. The first main electrode 112 is joined to the first conductor plate 120 via a conductive joining member. The second main electrode 114 is joined to a protrusion 130a of the second conductor plate 130 via a conductive joining member. The first control electrode 113 is electrically connected to the gate wire 140. The first main electrode 112 and the first control electrode 113 overlap each other in the stacking direction.

[0014] The semiconductor substrate 111 is made of, for example, Si, SiC, GAN, GA2O3, Al2O3, diamond, etc. The first main electrode 112 and the first control electrode 113 are formed by laminating Ni, Ti, W, Al, Ag, Au, etc., and their outermost surfaces are made of, for example, Ni, Cu, Ag, or Au. The gate wire 140 and the source sense wire 141 are made of, for example, Al, Cu, or a compound containing these.

[0015] The first conductor plate 120, the second conductor plate 130, the gate conductor plate 150, and the source sense conductor plate 151 are formed of, for example, Ni-plated Cu, and are electrically insulated from each other. The conductive joining material that joins the electrodes of the semiconductor chip 110 to the conductor plates is, for example, solder or a sintered material.

[0016] The protrusion 130a of the second conductor plate 130 has a bonding surface with an area equal to or smaller than that of the second main electrode 114. This configuration of the protrusion 130a makes it possible to provide a predetermined insulation distance between the peripheral region of the semiconductor chip 110 and the second conductor plate 130, thereby suppressing dielectric breakdown of the semiconductor chip 110 due to discharge.

[0017] The first bonding portion 141a does not overlap the first main electrode 112 of the semiconductor chip 110 in the stacking direction. In this way, by extending a part of the second conductor plate 130 from the semiconductor chip 110 to the outer part in the planar direction, this extended region is not the highest temperature on the second conductor plate 130, and therefore bonding the source sense wire 141 to this region can reduce the effect of heat on the source sense wire 141. This improves the reliability of the source sense wire 141.

[0018] It is sufficient that one bonding portion 141a is provided somewhere on the surface of the second conductive plate 130. The number of bonding portions 141a is not limited to one, and multiple bonding portions 141a may be provided. Since there is a degree of freedom in determining the length of the source sense wire 141, it may be used for short circuit detection by sensing using inductance.

[0019] (First Modification) (Figure 3) FIG. 3(a) is a plan view of the semiconductor device 100, and FIG. 3(b) is a cross-sectional view taken along the line B-B' of FIG. 3(a). The semiconductor device 100 may be configured such that the first conductive plate 120 is not provided below the bonding portion 141a in the stacking direction. By ensuring that the first bonding portion 141a does not overlap the first conductive plate 120 in the stacking direction, a support material 260 and a sheet 261 that compensates for the height error between the support material 260 and the second conductive plate 130 can be provided below the bonding portion 141a during the manufacturing process of the semiconductor device 100. By bonding the source sense wire 141 to the first bonding portion 141a of the second conductive plate 130 using a bonding device (not shown), sufficient strength can be ensured during wire bonding. The support material 260 is, for example, carbon, ceramics such as Al2O3, or a metal such as Cu. The sheet 261 is, for example, a rubber vibration-proof material.

[0020] (Second Modification) (Figure 4) Fig. 4(a) is a plan view of the semiconductor device 100, Fig. 4(b) is a plan view of the semiconductor device 100 in Fig. 4(a) with the second conductor plate 130 and the source sense wire 141 illustrated, and Fig. 4(c) is a cross-sectional view taken along CC' in Fig. 4(b). A second main electrode 114, a first control electrode 113, and a source sense electrode 315 which is a second control electrode electrically connected to the second main electrode 114 and has the same potential as the second main electrode 114 are provided on a semiconductor substrate 111 of the semiconductor chip 110.

[0021] The convex portion 130a of the second conductor plate 130 has a first convex shape for connecting the source sense electrode 315 and the second conductor plate 130, and a second convex shape for connecting the first main electrode 112 and the second conductor plate 130. The first convex shape has an area equal to or smaller than the area of ​​the second main electrode 114. The second convex shape has an area equal to or smaller than the area of ​​the source sense electrode 315. This increases the heat dissipation path and heat dissipation area from the top surface side of the semiconductor chip 110, thereby reducing thermal resistance.

[0022] Like the other electrodes, the source sense electrode 315 is formed by laminating Ni, Ti, W, Al, Ag, Au, etc., and its outermost surface is made of, for example, Ni, Cu, Ag, or Au. Note that a plurality of source sense electrodes 315 may be provided on the semiconductor substrate 111, and accordingly, a plurality of first convex shapes of the convex portion 130a connected to the source sense electrodes 315 may also be provided.

[0023] (Third Modification) (Figure 5) Fig. 5(a) is a plan view of the semiconductor device 100, and Fig. 5(b) is a cross-sectional view taken along the line D-D' of Fig. 5(a). The second conductor plate 130 has a stepped portion 130b that forms a surface that is lower than a surface 131 of the second conductor plate 130 in the stacking direction. A first bonding portion 141a is provided on the surface of the stepped portion 130b. Furthermore, the source sense wire 141 bonded to the bonding portion 141a has a height in the stacking direction that is lower than the surface 131 of the second conductor plate 130.

[0024] This allows the surface 131 of the second conductive plate 130 to be directly cooled, avoiding the first bonding portion 141a, which has the effect of reducing thermal resistance. Also, as shown in Fig. 9 described below, it is possible to prevent the source sense wire 141 from coming into contact with the insulating material 481 during double-sided cooling. Note that the step portion 130b has at least an area range 130c where it is not interfered with by a bonding tool of a bonding device (not shown).

[0025] (Fourth Modification) (Figure 6) Fig. 6(a) is a plan view of the semiconductor device 100, Fig. 6(b) is a plan view of the semiconductor device 100 in Fig. 6(a) showing the second conductor plate 130 and the source sense wire 141, and Fig. 6(c) is a cross-sectional view taken along the line E-E' of Fig. 6(b). As in the third modification, the semiconductor device 100 has a stepped portion 130b that is lower than the other surfaces of the second conductor plate 130, and a bonding portion 141a is formed on the stepped portion 130b. A supporting conductor plate 508 (third conductor plate), which is a conductor plate that serves as a support member for the second conductor plate 130, is provided below the stepped portion 130b in the stacking direction.

[0026] The supporting conductor plate 508 is made of, for example, Ni-plated Cu. The supporting conductor plate 508 and the second conductor plate 130 may be joined by a conductive joining material, such as solder or a sintered material. The supporting conductor plate 508 is electrically independent from components other than the second conductor plate 130. Although not shown, the stepped portion 130b has at least an area range 130c (FIG. 5) that is not interfered with by the bonding tool of the bonding device, as in the third modification. This increases the bonding strength of the wire. After the bonding of the wire to the first bonding portion 141a is completed, the supporting conductor plate 508 may be left as is or removed before the manufacturing of the semiconductor device 100 is completed.

[0027] (Fifth Modification) (Figure 7) In the semiconductor device 100, the second conductor plate 130 is not provided only in the region that overlaps with the first control electrode 113 of the semiconductor chip 110 in the stacking direction. By configuring the first control electrode 113 and the second conductor plate 130 so that they do not overlap with each other in the stacking direction, the gate wire 140 and the source sense wire 141 can be bonded at the same time in the manufacturing process of the semiconductor device 100, making it easier to manufacture the semiconductor device 100.

[0028] (Sixth Modification) (Figure 8) The semiconductor device 100 is provided with conductor plates above the first control electrode 113 (FIG. 7) and in the remaining portion in the stacking direction. The second conductor plate 130 is connected to the second main electrode 114 (FIG. 1). In addition, a surface electrode 731 (fourth conductor plate), which is a conductor plate electrically connected to the first control electrode 113 and electrically independent from the second conductor plate 130, is provided above the first control electrode 113 in the stacking direction.

[0029] The second conductor plate 130 has a first connection region 130d, which is a region in the stacking direction where the semiconductor chip 110 is not provided. The surface electrode 731 also has a second connection region 731a, which is a region that does not overlap with the first main electrode 112 of the semiconductor chip 110 in the stacking direction. A gate wire 140 is bonded to the first connection region 130d. A source sense wire 141 is bonded to the second connection region 731a.

[0030] The first bonding portion 141a of the first connection region 130d to which the source sense wire 141 is bonded does not overlap with the surface electrode 731 in the stacking direction. Moreover, the second bonding portion 731b of the second connection region 731a to which the gate wire 140 is bonded does not overlap with the first main electrode 112 in the stacking direction. The second conductor plate 130 and the surface electrode 731 have the same height in the stacking direction.

[0031] Therefore, the first connection region 130d and the second connection region 731a have a lower temperature than other parts of the conductive plate, and the thermal effects on the gate wire 140 and the source sense wire 141 connected thereto are reduced, which contributes to improving the reliability of each wire.

[0032] (double-sided cooling structure) (Figure 9) The semiconductor device 100 is sandwiched between cooling members 483 on both sides in the stacking direction, thereby forming a cooling mechanism for cooling the semiconductor chip 110. The cooling member 483 is made of, for example, Cu or Al, and has a comb-shaped portion through which the refrigerant and air flow, allowing the air and refrigerant to flow through gaps in the comb-shaped portion and cooling the semiconductor device 100.

[0033] Since the semiconductor device 100 is used as a power module, in order to prevent discharge when a high voltage is applied, the entire power module is sealed with an insulating sealing material 480. The sealing material 480 is formed by, for example, silicone gel or transfer molding.

[0034] The insulating material 481 is provided to insulate the cooling member 483 from the power module portion of the semiconductor device 100. The insulating material 481 is made of, for example, ceramics or a resin material.

[0035] Intermediate material 482 is provided to improve adhesion between cooling member 483 and the power module portion of semiconductor device 100. Intermediate material 482 is formed, for example, from a metal, a resin material, a carbon sheet, a compound of these, or a laminate of these.

[0036] The first conductive plate 120 has a protruding portion 120a that is not sealed in the sealing material 480 but protrudes outside the sealing material 480. Similarly, the source sense conductive plate 151 has a protruding portion 151a that is not sealed in the sealing material 480 but protrudes outside the sealing material 480. Providing such protruding portions 120a and 151a facilitates electrical connection with other components (not shown). Note that the portion that is not sealed in the sealing material 480 is not limited to the protruding portion 120a and the protruding portion 151a, and for example, the portion where the second conductive plate 130 and other components are connected may also be configured not to be sealed in the sealing material 480.

[0037] By adopting such a double-sided cooling structure, heat from the semiconductor chip 110 moves vertically and is dissipated toward the cooling member 483. Therefore, the source sense wire 141 is bonded at a position far from such a heat dissipation path and does not become hot, thereby ensuring the reliability of the source sense wire 141.

[0038] According to the embodiment of the present invention described above, the following advantageous effects are achieved.

[0039] (1) The semiconductor device 100 includes a semiconductor element 110 having a first main electrode 112 on one surface and a second main electrode 114 and a first control electrode 113 on the other surface, a first conductor plate 120 disposed on one surface of the semiconductor element 110 and joined to the first main electrode 112 via a conductive bonding member, a second conductor plate 130 disposed on the other surface of the semiconductor element 110 and joined to the second main electrode 114 via a conductive bonding member, and the first control electrode 113. and a second control bonding wire 141 joined to the second conductor plate 130, the first control electrode 113 and the first main electrode 112 overlapping each other in the stacking direction, the second control bonding wire 141 joined to a first bonding portion 141a provided on the surface of the second conductor plate 130, and the first bonding portion 141a not overlapping with the first main electrode 112 in the stacking direction. In this way, it is possible to provide a semiconductor device 100 in which the reliability of the source sense wire 141 is improved.

[0040] (2) The first bonding portion 141a does not overlap the first conductive plate 120 in the stacking direction. This ensures sufficient strength when the source sense wire 141 is bonded.

[0041] (3) The semiconductor element 110 has a second control electrode 315 electrically connected to the second main electrode 114, and the second conductor plate 130 is joined to the second control electrode 315. This increases the heat dissipation area and reduces the thermal resistance.

[0042] (4) The second conductor plate 130 has a step portion 130b that forms a surface that is lower than the surface of the second conductor plate 130 in the stacking direction, the first bonding portion 141a is provided on the surface of the step portion 130b, and the height 141b of the second control bonding wire 141 in the stacking direction is lower than the surface of the second conductor plate 130. By doing so, the surface of the second conductor plate 130 can be directly cooled, thereby reducing thermal resistance.

[0043] (5) The third conductive plate 508 is provided at the lower part of the step portion 130b in the stacking direction, which increases the wire bonding strength.

[0044] (6) The first control electrode 113 and the second conductor plate 130 do not overlap each other in the stacking direction, which makes it easier to manufacture the semiconductor device 100.

[0045] (7) A fourth conductor plate 731 is provided which is connected to the first control electrode 113, and a second bonding portion 731b to which the first control bonding wire 140 is joined is provided on the fourth conductor plate 731, the first bonding portion 141a does not overlap with the fourth conductor plate 731 in the stacking direction, and the second bonding portion 731b does not overlap with the first main electrode 112 in the stacking direction. This can improve the reliability of the wire.

[0046] The present invention is not limited to the above-described embodiments, and various modifications and combinations of other configurations are possible without departing from the spirit of the present invention. Furthermore, the present invention is not limited to those having all of the configurations described in the above-described embodiments, and includes those in which some of the configurations are omitted. [Explanation of symbols]

[0047] 100 Semiconductor device 110 Semiconductor Chips 111 Semiconductor substrate 112 1st main electrode 113 First control electrode 114 2nd main electrode 120 First conductor plate 120a 1st protrusion 130 Second conductor plate 130a Convex part 130b Step 130c Step area 130d First connection area 131 Second conductor plate surface 140 Gate Wire 141 Source Sense Wire 141a First Bonding Section 141b Source sense wire height position 150 Gate conductor plate 151 Source sense conductor plate 260 Support material 261 seats 315 Source sense electrode (second control electrode) 480 Encapsulating material 481 Insulation Materials 482 Intermediate materials 483 Cooling Materials 508 Supporting conductor plate 731 Top electrode 731a Second connection area 731b Second bonding section

Claims

1. a semiconductor element having a first main electrode on one surface and a second main electrode and a first control electrode on the other surface; a first conductor plate disposed on the one surface side of the semiconductor element and joined to the first main electrode via a conductive bonding member; and a second conductor plate disposed on the other surface side of the semiconductor element and joined to the second main electrode via the conductive bonding member. a first control bonding wire electrically connected to the first control electrode; a second control bonding wire joined to the second conductor plate, the first control electrode and the first main electrode overlap each other in a stacking direction, the second control bonding wire is bonded to a first bonding portion provided on a surface of the second conductor plate, The first bonding portion does not overlap the first main electrode in the stacking direction. Semiconductor device.

2. 2. The semiconductor device according to claim 1, The first bonding portion does not overlap the first conductive plate in the stacking direction. Semiconductor device.

3. 2. The semiconductor device according to claim 1, the semiconductor element has a second control electrode electrically connected to the second main electrode; The second conductive plate is joined to the second control electrode. Semiconductor device.

4. 2. The semiconductor device according to claim 1, the second conductor plate has a step portion that forms a surface that is lower than a surface of the second conductor plate in the stacking direction, the first bonding portion is provided on a surface of the step portion, The height of the second control bonding wire in the stacking direction is lower than the surface of the second conductor plate. Semiconductor device.

5. 5. The semiconductor device according to claim 4, a third conductive plate is provided below the step portion in the stacking direction; Semiconductor device.

6. 2. The semiconductor device according to claim 1, The first control electrode and the second conductor plate do not overlap each other in the stacking direction. Semiconductor device.

7. 7. The semiconductor device according to claim 6, a fourth conductor plate connected to the first control electrode; a second bonding portion to which the first control bonding wire is bonded is provided on the fourth conductor plate; the first bonding portion does not overlap the fourth conductor plate in the stacking direction, The second bonding portion does not overlap the first main electrode in the stacking direction. Semiconductor device.

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