Semiconductor Module

Abstract

To provide a semiconductor module capable of preventing the peeling of a sealing resin on the side where a connection section used for the connection to a semiconductor element is arranged.SOLUTION: A semiconductor module 1 includes: an outer frame 103; sealing resins 61u, 61v, 61w; gate signal output terminals 31ua-31vb; and partition sections 101, 102 laid across the outer flame 103 to partition a space 11 into a plurality of housing sections 111u, 111v, 111w, the gate signal output terminals 31ua-31vb with connection sections 311 exposed being arranged in the partition sections. The partition sections 101, 102 have: first surface parts 101c, 102c on a side where the connection sections 311 are arranged; and second surface parts 101d, 102d on a side where the connection sections 311 are not arranged, the second surface parts being formed such that peel strength against the sealing resins 61u, 61v, 61w is lower than the peel strength of the first surface parts 101c, 102c.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a semiconductor module that is applied to a power conversion device or the like. [Background technology]

[0002] In recent years, power semiconductor modules, mainly using insulated gate bipolar transistors (IGBTs), have come to be widely used in power conversion devices. A power semiconductor module is a power semiconductor device that incorporates one or more power semiconductor chips to form a part or the whole of a conversion connection, and has a structure in which the power semiconductor chips are electrically insulated from a base plate or a cooling surface.

[0003] Patent Document 1 discloses a semiconductor device that can reduce the occurrence of peeling of bonding wires. Patent Document 2 discloses a robust and reliable resin-sealed semiconductor device that prevents poor bonding between structural members of the device. Patent Document 3 discloses a semiconductor device that can suppress peeling of the sealing resin even when operated at high temperatures. Patent Document 4 discloses a metal press processing method that enables partial roughening treatment in a short time, and a resin-sealed metal part obtained by the method that ensures the adhesiveness and adhesion of the resin to the metal part for resin sealing and has excellent sealing properties and peel strength. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2014-229848 A [Patent Document 2] Japanese Patent Application Publication No. 6-268102 [Patent Document 3] JP 2012-204366 A [Patent Document 4] JP 2012-64880 A [Non-patent literature]

[0005] [Non-Patent Document 1] Ryuichi Kusama et al., MES2013 (23rd Microelectronics Symposium), September 2013, pp317-320, "Proposal of a peel test application method for semiconductor package stress design" Summary of the Invention [Problem to be solved by the invention]

[0006] Power semiconductor modules are required to be available in various sizes, from small to large, in response to the need for higher current and higher voltage resistance. Under such circumstances, stress increases on the surface of a structure that is in close contact with the sealing resin provided in the power semiconductor module, and there is a risk that the sealing resin will peel off from the structure. If the sealing resin peels off from the structure, there is a problem that a wire provided in the sealing resin and used for wire bonding will break.

[0007] An object of the present invention is to provide a semiconductor module capable of preventing peeling of the sealing resin on the side where a connection portion used for connection to a semiconductor element is disposed. [Means for solving the problem]

[0008] In order to achieve the above-mentioned object, a semiconductor module according to one embodiment of the present invention comprises an outer frame defining a space in which a plurality of semiconductor elements are arranged, a sealing resin formed in the space covering the plurality of semiconductor elements, a control terminal connected to the semiconductor element and outputting a control signal for controlling the semiconductor element, and a partition portion on which the control terminal is arranged with its connection portion with the semiconductor element exposed, the partition portion being stretched across the outer frame to divide the space into a plurality of regions, the partition portion having a first surface portion on the side on which the connection portion is arranged, and a second surface portion on the side on which the connection portion is not arranged, the second surface portion being formed so as to have a lower peel strength against the sealing resin than the first surface portion. Effect of the Invention

[0009] According to one aspect of the present invention, peeling of the sealing resin on the side where the connection portion used for connection to the semiconductor element is disposed can be prevented. [Brief description of the drawings]

[0010] [Figure 1] 1 is a plan view showing an example of a schematic configuration of a semiconductor module according to an embodiment of the present invention; [Diagram 2] 2 is a cross-sectional view taken along line XX in FIG. 1, showing an example of a schematic configuration of a semiconductor module according to an embodiment of the present invention. [Diagram 3] 2 is a circuit diagram showing an example of an inverter circuit provided in a semiconductor module according to an embodiment of the present invention; [Figure 4] 3 is a diagram for explaining a partition provided in the semiconductor module according to the embodiment of the present invention, and is a cross-sectional view showing an enlarged view of the vicinity of the partition shown in FIG. 2. FIG. [Diagram 5] 3 is a diagram for explaining a first surface portion and a second surface portion of a partition portion provided in the semiconductor module according to the embodiment of the present invention, and is a cross-sectional view showing an enlarged view of the vicinity of the partition portion shown in FIG. 2. [Figure 6] 4 is a graph illustrating the surface roughness of a first surface portion and a second surface portion of a partition portion provided in a semiconductor module according to an embodiment of the present invention. [Figure 7] 5 is a graph illustrating peel strength of a first surface portion and a second surface portion of a partition portion provided in a semiconductor module according to an embodiment of the present invention. [Figure 8] 8 is a diagram for explaining the peel strength of the first and second surface portions of a partition portion provided in a semiconductor module according to one embodiment of the present invention, and is a diagram for explaining a pudding cup test for measuring the peel strength shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Each embodiment of the present invention is an example of an apparatus or method for embodying the technical idea of ​​the present invention, and the technical idea of ​​the present invention does not specify the material, shape, structure, arrangement, etc. of the components to those described below. The technical idea of ​​the present invention can be modified in various ways within the technical scope defined by the claims.

[0012] A semiconductor module according to an embodiment of the present invention will be described with reference to Figures 1 to 8. First, a schematic configuration of the semiconductor module according to this embodiment will be described with reference to Figures 1 to 5. In this embodiment, a power conversion module capable of DC / AC conversion will be taken as an example of the semiconductor module. Note that in Figure 1, the sealing resin provided in the semiconductor module is omitted.

[0013] As shown in Fig. 1, the semiconductor module 1 according to this embodiment includes an outer frame 103 that defines a space 11 in which multiple semiconductor elements Sua, Sub, Sva, Svb, Swa, and Swb are arranged. The outer frame 103 defines the space 11 in a rectangular shape in a plan view. The outer frame 103 is formed of, for example, an insulating thermoplastic resin. Examples of the thermoplastic resin include polyphenylene sulfide (PPS) resin, polybutylene terephthalate (PBT) resin, polybutylene succinate (PBS) resin, polyamide (PA) resin, and acrylonitrile butadiene styrene (ABS) resin.

[0014] The semiconductor module 1 includes sealing resins 61u, 61v, and 61w formed in the space 11 to cover the semiconductor elements Sua to Swb. The sealing resins 61u, 61v, and 61w are formed of, for example, a material different from that of the outer frame 103. The sealing resins 61u, 61v, and 61w are formed of, for example, an epoxy resin. The sealing resins 61u, 61v, and 61w are sealing members that seal components such as the semiconductor elements Sua to Swb provided in the space 11 and the laminated substrates 14u, 14v, and 14w on which the semiconductor elements Sua to Swb are mounted. The sealing resins 61u, 61v, and 61w seal the laminated substrates 14u, 14v, and 14w, thereby improving the insulation between predetermined conductive patterns (described in detail later) formed on the laminated substrates 14u, 14v, and 14w. Furthermore, the sealing resins 61u, 61v, and 61w seal various control terminals (described in detail below) connected to the laminated substrates 14u, 14v, and 14w by wire bonding and wires used in the wire bonding, thereby suppressing stress and distortion generated at the joints of the various control terminals and the wires. As a result, the sealing resins 61u, 61v, and 61w can improve the reliability of the semiconductor module 1.

[0015] The semiconductor module 1 includes gate signal output terminals 31ua, 31ub, 31va, 31vb, 31wa, and 31wb (examples of control terminals) that are connected to the semiconductor elements Sua to Swb and output gate pulse signals (examples of control signals) that control the semiconductor elements Sua to Swb, and reference signal output terminals 32ua, 32ub, 32va, 32vb, 32wa, and 32wb (examples of control terminals) that output reference signals. The details of the terminals such as the gate signal output terminal 31ua will be described later.

[0016] The semiconductor module 1 has gate signal output terminals 31ua-31wb with exposed connection portions 31 with the semiconductor elements Sua-Swb and reference signal output terminals 32ua-32wb with exposed connection portions 31 with the semiconductor elements Sua-Swb arranged therein, and includes partition portions 101, 102 that are stretched across an outer frame 103 and divide a space 11 into a plurality of storage portions 111u, 111v, 111w (an example of a plurality of regions). The partition portions 101, 102 are integrally formed of the same material as the outer frame 103. The partition portions 101, 102 and the outer frame 103 form a case 10. The partition portions 101, 102 will be described in detail later.

[0017] 1, the case 10 divides the space 11 into three regions, a storage section 111u for storing an inverter section for a U phase, a storage section 111v for storing an inverter section for a V phase, and a storage section 111w for storing an inverter section for a W phase, by partitions 101 and 102. The partitions 101 divide a part of the space 11 into the storage section 111u and the storage section 111v, and the partitions 102 divide another part of the space 11 into the storage section 111v and the storage section 111w.

[0018] The storage section 111u has a rectangular shape in a plan view. The storage section 111u is defined by a part of the outer frame 103 arranged on three consecutive sides (two short sides and one long side) of the four outer periphery sides, and the partition section 101 arranged on the remaining side (the remaining long side). The storage section 111v has a rectangular shape in a plan view. The storage section 111v is defined by another part of the outer frame 103 arranged on the opposing short sides of the four outer periphery sides, and the partition sections 101 and 102 arranged on the opposing long sides. The storage section 111w has a rectangular shape in a plan view. The storage section 111w is defined by the remaining part of the outer frame 103 arranged on three consecutive sides (two short sides and one long side) of the four outer periphery sides, and the partition section 102 arranged on the remaining side (the remaining long side).

[0019] 1, the semiconductor module 1 has a U-phase laminated substrate 14u stored in the storage section 111u and a U-phase inverter circuit 15u mounted on the laminated substrate 14u. The semiconductor module 1 has a V-phase laminated substrate 14v stored in the storage section 111v and a V-phase inverter circuit 15v mounted on the laminated substrate 14v. The semiconductor module 1 has a W-phase laminated substrate 14w stored in the storage section 111w and a W-phase inverter circuit 15w mounted on the laminated substrate 14w.

[0020] 1, the semiconductor module 1 has a U-phase power input terminal 21u to which DC power is input from the outside, a V-phase power input terminal 21v to which the DC power is input, and a W-phase power input terminal 21w to which the DC power is input. Each of the power input terminals 21u, 21v, and 21w has a positive terminal 211 connected to the positive side of the DC power and a negative terminal 212 connected to the negative side of the DC power.

[0021] The semiconductor module 1 has a power output terminal 81u arranged in a part of the outer frame 103 and facing the power input terminal 21u across the storage section 111u. The semiconductor module 1 has a power output terminal 81v arranged in a part of the outer frame 103 and facing the power input terminal 21v across the storage section 111v. The semiconductor module 1 has a power output terminal 81w arranged in a part of the outer frame 103 and facing the power input terminal 21w across the storage section 111w.

[0022] A positive terminal 211 of the power input terminal 21u is connected to a positive electrode pattern 41 formed on the laminated substrate 14u and connected to a semiconductor element Sua. A negative terminal 212 of the power input terminal 21u is connected to a negative electrode pattern 42 formed on the laminated substrate 14u and connected to a semiconductor element Sub. The power output terminal 81u is connected to an output portion pattern 43 formed on the laminated substrate 14u. This allows the semiconductor module 1 to generate U-phase AC power by the inverter circuit 15u using DC power supplied from the outside via the power input terminal 21u, and to supply the generated U-phase AC power from the power output terminal 81u to a drive target, for example, a motor M (not shown in FIG. 1, see FIG. 3).

[0023] A positive terminal 211 of the power input terminal 21v is connected to a positive electrode pattern 41 formed on the laminated substrate 14v and connected to a semiconductor element Sva. A negative terminal 212 of the power input terminal 21v is connected to a negative electrode pattern 42 formed on the laminated substrate 14v and connected to a semiconductor element Svb. The power output terminal 81v is connected to an output portion pattern 43 formed on the laminated substrate 14v. This allows the semiconductor module 1 to generate V-phase AC power by the inverter circuit 15v using DC power supplied from the outside via the power input terminal 21v, and to supply the generated V-phase AC power from the power output terminal 81v to a drive target, for example, the motor M.

[0024] A positive terminal 211 of the power input terminal 21w is connected to a positive electrode portion pattern 41 formed on the laminated substrate 14w and connected to a semiconductor element Swa. A negative terminal 212 of the power input terminal 21w is connected to a negative electrode portion pattern 42 formed on the laminated substrate 14w and connected to a semiconductor element Swb. The power output terminal 81w is connected to an output portion pattern 43 formed on the laminated substrate 14w. This allows the semiconductor module 1 to generate W-phase AC power by the inverter circuit 15w using DC power supplied from the outside via the power input terminal 21w, and to supply the generated W-phase AC power from the power output terminal 81w to a drive target, for example, a motor M.

[0025] 1, the reference signal output terminal 32ua, the gate signal output terminal 31ua, the gate signal output terminal 31ub, and the reference signal output terminal 32ub connected to the inverter circuit 15u are arranged in this order from the power input terminal 21u side toward the power output terminal 81u side in the partition portion 101. The order and number of the gate signal output terminals 31ua, 31ub and the reference signal output terminals 32ua, 32ub arranged in the extending direction of the partition portion 101 are not limited to the order and number shown in FIG. 1, and may be different depending on the configuration and arrangement pattern of the inverter circuit 15u provided on the laminated substrate 14u.

[0026] In the partition portion 102, the reference signal output terminal 32va, the gate signal output terminal 31va, the gate signal output terminal 31vb, and the reference signal output terminal 32vb connected to the inverter circuit 15v are arranged in this order from the power input terminal 21v side toward the power output terminal 81v side. The order and number of the gate signal output terminals 31va, 31vb and the reference signal output terminals 32va, 32vb arranged in the extending direction of the partition portion 102 are not limited to the order and number shown in Fig. 1, and may be different depending on the configuration and arrangement pattern of the inverter circuit 15v provided on the laminated substrate 14v.

[0027] In the terminal arrangement region 103a, which is parallel to the partitions 101, 102 and is a part of the outer frame 103 that defines the storage section 111w, the reference signal output terminal 32wa, the gate signal output terminal 31wa, the gate signal output terminal 31wb, and the reference signal output terminal 32wb connected to the inverter circuit 15w are arranged in this order from the power input terminal 21w side toward the power output terminal 81w side. The order and number of the gate signal output terminals 31wa, 31wb and the reference signal output terminals 32wa, 32wb arranged in the extension direction of the terminal arrangement region 103a are not limited to the order and number shown in FIG. 1 and may be different depending on the configuration and arrangement pattern of the inverter circuit 15w provided on the laminated substrate 14w.

[0028] The gate signal output terminal 31ua and the reference signal output terminal 32ua arranged in the partition portion 101 are electrically connected to the semiconductor element Sua constituting the inverter circuit 15u by wire bonding. Specifically, the connection portion 311 of the gate signal output terminal 31ua and the connection portion 321 of the reference signal output terminal 32ua are connected to the semiconductor element Sua by individual wires 150. In addition, the input portion 312 of the gate signal output terminal 31ua and the input portion 322 of the reference signal output terminal 32ua are each connected to a control circuit (not shown) that controls the inverter circuits 15u, 15v, 15w.

[0029] The gate signal output terminal 31ub and the reference signal output terminal 32ub arranged in the partition portion 101 are electrically connected to the semiconductor element Sub constituting the inverter circuit 15u by wire bonding. Specifically, the connection portion 311 of the gate signal output terminal 31ub and the connection portion 321 of the reference signal output terminal 32ub are connected to the semiconductor element Sub by different wires 150. In addition, the input portion 312 of the gate signal output terminal 31ua and the input portion 322 of the reference signal output terminal 32ua are each connected to a control circuit (not shown) that controls the inverter circuits 15u, 15v, 15w.

[0030] The gate signal output terminal 31va and the reference signal output terminal 32va arranged in the partition portion 102 are electrically connected to the semiconductor element Sva constituting the inverter circuit 15v by wire bonding. Specifically, the connection portion 311 of the gate signal output terminal 31va and the connection portion 321 of the reference signal output terminal 32va are connected to the semiconductor element Sva by individual wires 150. In addition, the input portion 312 of the gate signal output terminal 31va and the input portion 322 of the reference signal output terminal 32va are each connected to a control circuit (not shown) that controls the inverter circuits 15u, 15v, and 15w.

[0031] The gate signal output terminal 31vb and the reference signal output terminal 32vb arranged in the partition portion 102 are electrically connected to the semiconductor element Svb constituting the inverter circuit 15v by wire bonding. Specifically, the connection portion 311 of the gate signal output terminal 31vb and the connection portion 321 of the reference signal output terminal 32vb are connected to the semiconductor element Svb by different wires 150. In addition, the input portion 312 of the gate signal output terminal 31va and the input portion 322 of the reference signal output terminal 32va are each connected to a control circuit (not shown) that controls the inverter circuits 15u, 15v, and 15w.

[0032] The gate signal output terminal 31wa and the reference signal output terminal 32wa arranged in the terminal arrangement region 103a of the outer frame 103 are electrically connected to the semiconductor element Swa constituting the inverter circuit 15w by wire bonding. Specifically, the connection portion 311 of the gate signal output terminal 31wa and the connection portion 321 of the reference signal output terminal 32wa are connected to the semiconductor element Swa by individual wires 150. In addition, the input portion 312 of the gate signal output terminal 31wa and the input portion 322 of the reference signal output terminal 32wa are each connected to a control circuit (not shown) that controls the inverter circuits 15u, 15v, and 15w.

[0033] The gate signal output terminal 31wb and the reference signal output terminal 32wb arranged in the terminal arrangement region 103a of the outer frame 103 are electrically connected to the semiconductor element Swb constituting the inverter circuit 15w by wire bonding. Specifically, the connection portion 311 of the gate signal output terminal 31wb and the connection portion 321 of the reference signal output terminal 32wb are connected to the semiconductor element Swb by different wires 150. In addition, the input portion 312 of the gate signal output terminal 31wa and the input portion 322 of the reference signal output terminal 32wa are each connected to a control circuit (not shown) that controls the inverter circuits 15u, 15v, and 15w.

[0034] 2, the semiconductor module 1 has a cooler 16 attached to the case 10. The cooler 16 is mechanically fixed to the case 10 by, for example, an adhesive 161. The laminated substrates 14u, 14v, and 14w are, for example, soldered to the cooler 16. This allows the semiconductor module 1 to release heat generated from the semiconductor elements Sua to Swb provided on each of the laminated substrates 14u, 14v, and 14w to the outside via the cooler 16.

[0035] The laminated substrate 14u arranged in the storage section 111u has a rectangular flat insulating substrate 141 and a rectangular flat heat transfer member 142 formed on the lower surface (cooler 16 side) of the insulating substrate 141. The insulating substrate 141 is made of, for example, ceramic. The heat transfer member 142 is made of, for example, copper. The heat transfer member 142 is connected to the cooler 16 by, for example, soldering. An inverter circuit 15u is provided on the upper surface of the insulating substrate 141 (the surface opposite to the surface on which the heat transfer member 142 is provided).

[0036] The laminated substrate 14u arranged in the storage section 111u and the inverter circuit 15u provided on the upper surface of the insulating substrate 141 of the laminated substrate 14u are covered with the sealing resin 61u formed in the storage section 111u. In addition, the wire 150 connecting the gate signal output terminal 31ub and the semiconductor element Sub, the wire 150 connecting the semiconductor element Sub and the output part pattern 43, and other wires 150 (not shown in FIG. 2) used for wire bonding in the inverter circuit 15u are also covered with the sealing resin 61u. The sealing resin 61u seals the inverter circuit 15u and the like in a state where it fills the space constituting the storage section 111u. As a result, the sealing resin 61u is also formed in the gaps between the positive electrode part pattern 41, the negative electrode part pattern 42, and the output part pattern 43 formed on the insulating substrate 141. As a result, the sealing resin 61u can improve the insulation of the laminated substrate 14u. The sealing resin 61u is formed in the storage section 111u while covering metal parts such as the connection parts 311 of the gate signal output terminals 31ua and 31ub, the connection parts 321 of the reference signal output terminals 32ub and 32ub, and the connection parts and wires 150 used for electrical connection in the inverter circuit 15u. As a result, the sealing resin 61u seals the connection parts and wires 150, and thus it is possible to suppress stress and distortion occurring at the joints of the connection parts and wires 150, thereby improving the reliability of the semiconductor module 1.

[0037] As shown in FIG. 2, the laminated substrate 14v arranged in the storage section 111v and the sealing resin 61v formed in the storage section 111v have the same state as the laminated substrate 14u and the sealing resin 61u in the storage section 111u. Therefore, the sealing resin 61v is also formed in the gaps between the positive electrode part pattern 41, the negative electrode part pattern 42, and the output part pattern 43 formed on the insulating substrate 141 of the laminated substrate 14v. As a result, the sealing resin 61v can improve the insulation of the laminated substrate 14v. In addition, the sealing resin 61v is formed in the storage section 111u in a state where it covers metal parts such as the connection parts 311 of the gate signal output terminals 31va and 31vb, the connection parts 321 of the reference signal output terminals 32vb and 32vb, the connection parts used for electrical connection in the inverter circuit 15v, and the wires 150. As a result, by sealing the connection parts and the wires 150, the sealing resin 61v can suppress stress and distortion occurring at the joints of each connection part and the wires 150, thereby improving the reliability of the semiconductor module 1.

[0038] As shown in FIG. 2, the laminated substrate 14w arranged in the storage section 111w and the sealing resin 61w formed in the storage section 111w have the same state as the laminated substrate 14u and the sealing resin 61u in the storage section 111u. Therefore, the sealing resin 61w is also formed in the gaps between the positive electrode part pattern 41, the negative electrode part pattern 42, and the output part pattern 43 formed on the insulating substrate 141 of the laminated substrate 14w. As a result, the sealing resin 61w can improve the insulation of the laminated substrate 14w. In addition, the sealing resin 61w is formed in the storage section 111w in a state where it covers metal parts such as the connection parts 311 of the gate signal output terminals 31wa and 31wb, the connection parts 321 of the reference signal output terminals 32wb and 32wb, the connection parts used for electrical connection in the inverter circuit 15w, and the wires 150. As a result, by sealing the connection parts and the wires 150, the sealing resin 61w can suppress stress and distortion occurring at the joints of the connection parts and the wires 150, thereby improving the reliability of the semiconductor module 1.

[0039] Next, the circuit configuration of the inverter circuits 15u, 15v, and 15w provided in the semiconductor module 1 will be described with reference to FIG.

[0040] 3, the inverter circuit 15u provided in the semiconductor module 1 includes a semiconductor element Sua and a semiconductor element Sub connected in series between a positive terminal 211 and a negative terminal 212 of a power input terminal 21u. A connection between the semiconductor element Sua and the semiconductor element Sub is connected to a power output terminal 81u from which U-phase AC power is output. In the inverter circuit 15u, the semiconductor element Sua forms an upper arm of the U-phase AC power, and the semiconductor element Sub forms a lower arm of the U-phase AC power.

[0041] The inverter circuit 15v provided in the semiconductor module 1 includes semiconductor elements Sva and Svb connected in series between the positive terminal 211 and the negative terminal 212 of the power input terminal 21v. The connection between the semiconductor elements Sva and Svb is connected to a power output terminal 81v from which V-phase AC power is output. The semiconductor element Sva constitutes the upper arm of the V-phase AC power, and the semiconductor element Svb constitutes the lower arm of the V-phase AC power.

[0042] The inverter circuit 15w provided in the semiconductor module 1 includes semiconductor elements Swa and Swb connected in series between the positive terminal 211 and the negative terminal 212 of the power input terminal 21w. The connection between the semiconductor elements Swa and Swb is connected to a power output terminal 81w from which W-phase AC power is output. The semiconductor element Swa constitutes the upper arm of the W-phase AC power, and the semiconductor element Swb constitutes the lower arm of the W-phase AC power.

[0043] As shown in Fig. 3, the semiconductor element Sua has a transistor Qua, which is, for example, an insulated gate bipolar transistor (IGBT), and a free wheel diode Dua connected in anti-parallel to the transistor Qua. The transistor Qua and the free wheel diode Dua are, for example, formed on a single semiconductor substrate and integrated into a single chip. The semiconductor element Sub has a transistor Qub, which is, for example, an IGBT, and a free wheel diode Dub connected in anti-parallel to the transistor Qub. The transistor Qub and the free wheel diode Dub are, for example, formed on a single semiconductor substrate and integrated into a single chip.

[0044] The collector C of the transistor Qua and the cathode K of the freewheeling diode Dua are connected to each other and connected to the positive terminal 211 of the power input terminal 21u. The emitter E of the transistor Qua and the anode A of the freewheeling diode Dua are connected to each other. The collector C of the transistor Qub and the cathode K of the freewheeling diode Dub are connected to each other. The emitter E of the transistor Qua and the anode A of the freewheeling diode Dub are connected to each other and connected to the power output terminal 81u. The emitter E of the transistor Qub and the anode A of the freewheeling diode Dub are connected to each other and connected to the negative terminal 212 of the power input terminal 21u.

[0045] A gate G of the transistor Qua is connected to a connection part 311 (see FIG. 1) of the gate signal output terminal 31ua by a wire 150. An emitter E of the transistor Qua is connected to a connection part 321 (see FIG. 1) of the reference signal output terminal 32ua by a wire 150.

[0046] As shown in Fig. 3, the semiconductor element Sva has a transistor Qva, for example an IGBT, and a free wheel diode Dva connected in anti-parallel to the transistor Qva. The transistor Qva and the free wheel diode Dva are formed, for example, on a single semiconductor substrate and integrated into a single chip. The semiconductor element Svb has a transistor Qvb, for example an IGBT, and a free wheel diode Dvb connected in anti-parallel to the transistor Qvb. The transistor Qvb and the free wheel diode Dvb are formed, for example, on a single semiconductor substrate and integrated into a single chip.

[0047] The collector C of the transistor Qva and the cathode K of the freewheeling diode Dva are connected to each other and connected to the positive terminal 211 of the power input terminal 21v. The emitter E of the transistor Qva and the anode A of the freewheeling diode Dva are connected to each other. The collector C of the transistor Qvb and the cathode K of the freewheeling diode Dvb are connected to each other. The emitter E of the transistor Qva and the anode A of the freewheeling diode Dva, and the collector C of the transistor Qvb and the cathode K of the freewheeling diode Dvb are connected to each other and connected to the power output terminal 81v. The emitter E of the transistor Qvb and the anode A of the freewheeling diode Dvb are connected to each other and connected to the negative terminal 212 of the power input terminal 21v.

[0048] The gate G of the transistor Qva is connected to the connection part 311 (see FIG. 1) of the gate signal output terminal 31va by a wire 150. The emitter E of the transistor Qva is connected to the connection part 321 (see FIG. 1) of the reference signal output terminal 32va by a wire 150.

[0049] As shown in Fig. 3, the semiconductor element Swa has a transistor Qwa, for example an IGBT, and a free wheel diode Dwa connected in anti-parallel to the transistor Qwa. The transistor Qwa and the free wheel diode Dwa are formed, for example, on a single semiconductor substrate and integrated into a single chip. The semiconductor element Swb has a transistor Qwb, for example an IGBT, and a free wheel diode Dwb connected in anti-parallel to the transistor Qwb. The transistor Qwb and the free wheel diode Dwb are formed, for example, on a single semiconductor substrate and integrated into a single chip.

[0050] The collector C of the transistor Qwa and the cathode K of the freewheeling diode Dwa are connected to each other and connected to the positive terminal 211 of the power input terminal 21w. The emitter E of the transistor Qwa and the anode A of the freewheeling diode Dwa are connected to each other. The collector C of the transistor Qwb and the cathode K of the freewheeling diode Dwb are connected to each other. The emitter E of the transistor Qwa and the anode A of the freewheeling diode Dwa, and the collector C of the transistor Qwb and the cathode K of the freewheeling diode Dwb are connected to each other and connected to the power output terminal 81w. The emitter E of the transistor Qwb and the anode A of the freewheeling diode Dwb are connected to each other and connected to the negative terminal 212 of the power input terminal 21w.

[0051] The gate G of the transistor Qwa is connected to the connection part 311 (see FIG. 1) of the gate signal output terminal 31wa by a wire 150. The emitter E of the transistor Qwa is connected to the connection part 321 (see FIG. 1) of the reference signal output terminal 32wa by a wire 150.

[0052] A gate pulse signal output from a control circuit (not shown) is input to the gate G of a transistor Qua provided in the semiconductor element Sua, and a DC reference signal output from the control circuit is input to the emitter E of the transistor Qua provided in the semiconductor element Sua. Therefore, the potential difference between the potential of the gate pulse signal and the potential of the reference signal is applied to the transistor Qua as a gate-emitter voltage.

[0053] A potential difference between the potential of the gate pulse signal output from the control circuit and the potential of the reference signal is applied as a gate-emitter voltage to the transistor Qub provided in the semiconductor element Sub. A potential difference between the potential of the gate pulse signal output from the control circuit and the potential of the reference signal is applied as a gate-emitter voltage to the transistor Qva provided in the semiconductor element Sva. A potential difference between the potential of the gate pulse signal output from the control circuit and the potential of the reference signal is applied as a gate-emitter voltage to the transistor Qvb provided in the semiconductor element Svb. A potential difference between the potential of the gate pulse signal output from the control circuit and the potential of the reference signal is applied as a gate-emitter voltage to the transistor Qwa provided in the semiconductor element Swa. A potential difference between the potential of the gate pulse signal output from the control circuit and the potential of the reference signal is applied as a gate-emitter voltage to the transistor Qwb provided in the semiconductor element Swb.

[0054] For example, the transistors Qua, Qub, Qva, Qvb, Qwa, and Qwb are turned on when the voltage level of the gate pulse signal is high, and turned off when the voltage level of the gate pulse signal is low. Although detailed description is omitted, the transistors Qua and Qub provided in the inverter circuit 15u, the transistors Qva and Qvb provided in the inverter circuit 15v, and the transistors Qwa and Qwb provided in the inverter circuit 15w are repeatedly turned on and off at a predetermined timing and combination. This allows the semiconductor module 1 to supply U-phase AC power, V-phase AC power, and W-phase AC power, the phases of which are shifted from each other by a predetermined amount, to the motor M from the power output terminals 81u, 81v, and 81w of the inverter circuits 15u, 15v, and 15w.

[0055] (Partition configuration) Next, the configuration of the partitions 101, 102 provided in the semiconductor module 1 according to this embodiment will be described using Figures 4 and 5 while referring to Figures 1 to 3. The partitions 101 and 102 have the same configuration. Therefore, the configuration of the partitions 101, 102 will be described using the partition 101 as an example. Figures 4 and 5 show an enlarged view of the vicinity of the partition 101 shown in Figure 2.

[0056] As shown in Fig. 4, the partition 101 has a base 101a fixed to the cooler 16, and a wall 101b protruding from the base 101a. The base 101a and the wall 101b are integrally formed. The wall 101b is disposed on the base 101a, biased toward the storage section 111v. This gives the partition 101 a curved shape. The partition 101 has an L-shaped cross section perpendicular to the extension direction.

[0057] The gate signal output terminal 31ub has a shape that follows the shape of the bent partition 101. Therefore, the gate signal output terminal 31ub also has a bent shape, and a cross section perpendicular to the extending direction of the partition 101 is L-shaped. The gate signal output terminal 31ub has a connection portion 311 arranged on the base 101a and an input portion 312 arranged on the wall 101b. A part of the connection portion 311 is exposed from the base 101a. A certain area including a tip of the input portion 312 is exposed from the wall 101b. The input portion 312 exposed from the wall 101b is connected to a control circuit.

[0058] As described above, the semiconductor element Sub and the gate signal output terminal 31ub are connected by wire bonding. The wire 150 used for wire bonding is connected to the connection portion 311 of the gate signal output terminal 31ub. Therefore, the connection portion 311 is a joint portion between the semiconductor element Sub and the wire 150. As a result, a gate pulse signal generated by the control circuit is input to the gate G of the transistor Qub (see FIG. 3) provided in the semiconductor element Sub via the input portion 312 of the gate signal output terminal 31ub, the connection portion 311, and the wire 150.

[0059] The partition 101 has a first surface 101c on the side where the connection portion 311 is arranged, and a second surface 101d on the side where the connection portion 311 is not arranged, which is formed so as to have a lower peel strength against the sealing resin 61u than the first surface 101c. The first surface 101c is also the side where the connection portion 321 is arranged. More specifically, as shown by the thick solid line in FIG. 5, the first surface 101c is a region of the surface of the base 101a and the wall 101b of the partition 101 facing the storage portion 111u, excluding the connection portions 311 and 321. Also, as shown by the thick dashed line in FIG. 5, the second surface 101d is the surface of the base 101a and the wall 101b of the partition 101 facing the storage portion 111v.

[0060] The semiconductor module 1 is configured such that the surface roughness of the first surface portion 101c is different from the surface roughness of the second surface portion 101d, so that the peel strength of the first surface portion 101c is higher than the peel strength of the second surface portion 101d. Specifically, the first surface portion 101c is formed to have a surface roughness greater than that of the second surface portion 101d. In other words, when the surface roughness of the first surface portion 101c is SR1 and the surface roughness of the second surface portion 101d is SR2, the partition portion 101 is formed to satisfy the relationship of the following formula (1). SR1>SR2 (1)

[0061] By roughening the surface of the partition portion 101, fine irregularities are formed on the surface of the partition portion 101. This increases the contact area between the sealing resin 61u and the partition portion 101, thereby increasing the peel strength to the sealing resin 61u. In addition, the anchor effect of the irregularities formed on the surface of the partition portion 101 increases the peel strength to the sealing resin 61u. Therefore, the peel strength of the first surface portion 101c to the sealing resin 61u is higher than the peel strength of the second surface portion 101d to the sealing resin 61v.

[0062] The case 10 is molded by insert molding in which a heated and melted thermoplastic resin is injected into an injection molding die into which the power input terminals 21u, 21v, 21w, the power output terminals 81u, 81v, 81w, the gate signal output terminals 31ua, 31ub, 31va, 31vb, 31wa, 31wb, and the reference signal output terminals 32ua, 32ub, 32va, 32vb, 32wa, 32wb are inserted, and the resin is integrated with the inserted gate signal output terminals 31ua, etc. For this reason, among the surfaces of the injection molding die, the surfaces for forming the first surface portion 101c of the partition portion 101 and the first surface portion 102c of the partition portion 102 (see FIG. 1) are roughened by, for example, sandblasting to make them rough. On the other hand, among the surfaces of the injection molding die, the surfaces for forming the second surface portion 101d of the partition portion 101 and the second surface portion 102d of the partition portion 102 (see FIG. 1) are not roughened and are made smoother than the surfaces for forming the first surface portions 101c and 102c. This makes it possible to form the partition portions 101 and 102 that satisfy the relationship of formula (1).

[0063] Although the details will be described later, when a temperature load is applied to the semiconductor module 1 and deformation occurs in the sealing resin of the semiconductor module 1, tensile stresses in opposite directions are generated in the first surface portion 101c and the second surface portion 101d of the partition portion 101, as shown by the thick arrow in FIG. 5. In other words, tensile stresses in opposite directions are applied to both sides of the partition portion 101. Since the second surface portion 101d has a lower peel strength against the sealing resin 61u than the first surface portion 101c, when tensile stress is generated in the first surface portion 101c and the second surface portion 101d, the second surface portion 101d in which a tensile stress stronger than the peel strength is generated is peeled off from the sealing resin 61u. This reduces the tensile stress applied to the first surface portion 101c. As a result, it is possible to prevent breakage of the wire 150 at the connection portion 311 of the gate signal output terminal 31ub arranged in the partition portion 101.

[0064] As described above, the semiconductor element Sua is connected to the gate signal output terminal 31ua and the reference signal output terminal 32ua by wire bonding. The semiconductor element Sub is connected to the gate signal output terminal 31ub and the reference signal output terminal 32ub by wire bonding. Therefore, the connection portion 311 of the gate signal output terminal 31ua and the connection portion 321 of the reference signal output terminal 32ua are joints between the semiconductor element Sua and the wire 150. Similarly, the connection portion 311 of the gate signal output terminal 31ub and the connection portion 321 of the reference signal output terminal 32ub are joints between the semiconductor element Sub and the wire 150.

[0065] The gate signal output terminal 31ua and the reference signal output terminals 32ua, 32ub arranged in the partition portion 101 have the same configuration as the gate signal output terminal 31ub. Therefore, even if the semiconductor module 1 is deformed due to a temperature load, it is possible to prevent breakage of the wire 150 at the connection portion 311 of the gate signal output terminal 31ua arranged in the partition portion 101 and at the connection portions 321 (see FIG. 1) of the reference signal output terminals 32ua, 32ub.

[0066] The partition portion 102 has the same structure as the partition portion 101. That is, as shown in Fig. 1 and Fig. 2, the partition portion 102 has a base portion 102a having the same shape as the base portion 101a of the partition portion 101, and a wall portion 102b having the same shape as the wall portion 101b of the partition portion 101. Therefore, in the partition portion 102, the gate signal output terminals 31va, 31vb and the reference signal output terminals 32va, 32vb are arranged in a bent state so as to follow the bent shape of the partition portion 102, similar to the gate signal output terminal 31ua and the like arranged in the partition portion 101.

[0067] The partition 102 has a first surface 102c on the side where the connection portion 311 is arranged, and a second surface 102d on the side where the connection portion 311 is not arranged, which is formed so as to have a lower peel strength against the sealing resins 61v and 61w than the first surface 102c. The first surface 102c is also the side where the connection portion 321 of the reference signal output terminals 32va and 32vb is arranged. The first surface 102c is a region of the surface of the base 102a and the wall 102b of the partition 102 facing the storage section 111v, excluding the connection portion 321. The second surface 102d is the surface of the base 102a and the wall 102b of the partition 102 facing the storage section 111w. Similarly to the partition 101, the partition 102 is configured such that the surface roughness of the first surface portion 102c is made different from the surface roughness of the second surface portion 102d, so that the peel strength of the first surface portion 102c is made higher than the peel strength of the second surface portion 102d. Specifically, the first surface portion 102c is formed so as to have a larger surface roughness than the second surface portion 102d.

[0068] As in the case of roughening the first surface portion 101c of the partition portion 101, among the surfaces of the injection molding die used to form the case 10, the surface for forming the first surface portion 102c of the partition portion 102 is roughened by, for example, sandblasting to make it a rough surface. On the other hand, among the surfaces of the injection molding die, the surface for forming the second surface portion 102d (see FIG. 1) of the partition portion 102 is not roughened and is made smoother than the surface for forming the first surface portion 102c. As a result, when the surface roughness of the first surface portion 102c is SR1 and the surface roughness of the second surface portion 102d is SR2, the partition portion 102 is formed so as to satisfy the relationship of the above-mentioned formula (1).

[0069] In this way, since the partition 102 has a structure similar to that of the partition 101, even if deformation due to temperature load occurs in the semiconductor module 1, breakage of the wire 150 at each connection part 311 of the gate signal output terminals 31va, 31vb arranged in the partition 102 and at each connection part 321 of the reference signal output terminals 32va, 32vb can be prevented.

[0070] 1 and 2, the terminal arrangement region 103a of the outer frame 103, in which the gate signal output terminals 31wa, 31wb and the reference signal output terminals 32wa, 32wb connected to the laminated substrate 14w are arranged, has a curved shape similar to the partitions 101, 102. Therefore, the gate signal output terminals 31wa, 31wb and the reference signal output terminals 32wa, 32wb are arranged in the outer frame 103 in a curved state so as to follow the curved shape of the terminal arrangement region 103a of the outer frame 103.

[0071] In the terminal arrangement region 103a of the outer frame 103, the side where the connecting parts 311, 321 are not arranged is the outside, and no sealing resin is formed thereon. Therefore, even if the semiconductor module 1 is deformed based on a temperature load, the terminal arrangement region 103a is not subjected to tensile stress from the outside, unlike the partition parts 101, 102. As a result, when the semiconductor module 1 is deformed, the wire 150 joined to the connecting parts 311, 321 arranged in the terminal arrangement region 103a is not likely to be subjected to tensile stress from the sealing resin 61w formed in the storage part 111w. Therefore, in this embodiment, the surface of the terminal arrangement region 103a on the side where the connecting parts 311, 321 are arranged may be roughened, but may not be roughened, unlike the first surface parts 101c, 102c.

[0072] (Function and effect of the partition) Next, the function and effect of the partitions 101, 102 provided in the semiconductor module 1 will be described with reference to FIGS. 1 to 5 and with reference to FIGS.

[0073] In the semiconductor module 1 according to the present embodiment, as described above, the case 10 and the cooler 16 are fixed in a state in which the laminated substrates 14u, 14v, and 14w soldered to the cooler 16 are housed in the housings 111u, 111v, and 111w. Furthermore, the housings 111u, 111v, and 111w are provided with sealing resins 61u, 61v, and 61w that cover the laminated substrates 14u, 14v, and 14w (see FIG. 2). The cooler 16 is made of, for example, aluminum, and the insulating substrates 141 provided on each of the laminated substrates 14u, 14v, and 14w are made of, for example, ceramic. For this reason, the linear expansion coefficient of the cooler 16 is about 7 to 8 times larger than the linear expansion coefficient of the insulating substrate 141.

[0074] A thermal shock test is performed on the semiconductor module 1 as part of the reliability test. In the thermal shock test, a temperature load is applied to the semiconductor module 1, and the semiconductor module 1 is deformed so as to bend in a forward warping direction in the longitudinal direction of the case 10 due to the difference in the linear expansion coefficient between the cooler 16 and the insulating substrate 141. Therefore, stress is applied between the partition 101 and the sealing resins 61u and 61v, and stress is applied between the partition 102 and the sealing resins 61v and 61w. As a result, as shown by the thick straight arrows in FIG. 2, symmetric tensile stress is applied to the partition 101, and symmetric tensile stress is also applied to the partition 102. As a result, a force is applied to the sealing resin 61u in a direction to peel it off from the partition 101, a force is applied to the sealing resin 61v in a direction to peel it off from the partitions 101 and 102, and a force is applied to the sealing resin 61w in a direction to peel it off from the partition 102. In addition to the thermal shock test, the semiconductor module 1 may be deformed due to shrinkage of the sealing resins 61u, 61v, and 61w after formation, and tensile stress may be applied to the partitions 101 and 102 from the sealing resins 61u, 61v, and 61w.

[0075] A cross-sectional disassembly investigation of a partition of a conventional semiconductor module and a simulation analysis of the tensile stress applied to the partition were performed. The conventional semiconductor module investigated has a similar structure to the semiconductor module 1 according to the present embodiment, except that the roughness of the first surface portion and the second surface portion of the partition portion are the same.

[0076] Simulation analysis of tensile stress confirmed that tensile stress of approximately the same magnitude is applied to the first and second surface portions of the partition in opposite directions. In addition, in a cross-sectional disassembly investigation, peeling between the partition and the sealing resin was confirmed on either the first or second surface portion of the partition. However, peeling of the sealing resin from the first surface portion and peeling of the sealing resin from the second surface portion did not occur simultaneously.

[0077] The connection part of the control terminal exposed on the first surface and the wire connected to the connection part are covered with the sealing resin. In other words, the connection part and the wire connected to the connection part are embedded in the sealing resin and fixed to the sealing resin. Therefore, when the semiconductor module provided with the partition part is deformed in the forward warping direction and the sealing resin is peeled off from the first surface part of the partition part, the wire embedded in the sealing resin is subjected to a force in a direction away from the partition part. As a result, the wire is subjected to a force in a direction away from the connection part of the control terminal arranged on the partition part, and the wire is broken at the connection part, which may cause an open defect in the semiconductor module. When the wire is broken, the gate pulse signal and the reference signal are no longer input from the control circuit to the inverter circuit, so that the semiconductor module does not perform a predetermined operation and is no longer able to supply power to the driven object, such as a motor.

[0078] In contrast, in the semiconductor module 1 according to the present embodiment, in consideration of the result of the cross-sectional analysis that the sealing resin does not peel off simultaneously on both sides of the partition, the partition 101 is formed so that the peel strength of the first surface portion 101c against the sealing resin 61u is higher than the peel strength of the second surface portion 101d against the sealing resin 61v. When tensile stresses in opposite directions and substantially the same are applied to the first surface portion 101c side and the second surface portion 101d side of the partition 101, the sealing resin 61v is peeled off from the second surface portion 101d before the sealing resin 61u is peeled off from the first surface portion 101c. This releases one of the tensile stresses applied to the partition 101 caused by the deformation of the semiconductor module 1 into a forward warp state. As a result, the tensile stress applied from the sealing resin 61u to the first surface portion 101c is reduced to a level at which the wire 150 does not break. This prevents the wire 150 from breaking at the connection portion 31. Although detailed description will be omitted, the partition 102 is also formed so that the peel strength of the first surface portion 102c against the sealing resin 61v is higher than the peel strength of the second surface portion 102d against the sealing resin 61w. Therefore, the partition 102 acts on the sealing resins 61v, 61w in the same manner as the partition 101 acts on the sealing resins 61u, 61v, so that breakage of the wire 150 at each of the connection portions 311, 321 provided on the partition 102 is prevented.

[0079] Incidentally, even if the sealing resins 61v, 61w peel off from the second surface portions 101d, 102d, the inverter circuits 15v, 15w and the laminated substrates 14v, 14w are covered with the sealing resins 61v, 61w. Therefore, the semiconductor module 1 can obtain the effect of improving insulation and reliability even after the sealing resins 61v, 61w peel off from the second surface portions 101d, 102d.

[0080] FIG. 6 is a graph showing the surface roughness of the first surface portions 101c, 102c and the second surface portions 101d, 102d of the partition portions 101, 102. "Untreated" on the horizontal axis of the graph shown in FIG. 6 indicates a state in which the surface is not roughened, and corresponds to the second surface portions 101d, 102d. "Roughened" on the horizontal axis of the graph shown in FIG. 6 indicates a state in which the surface is roughened, and corresponds to the first surface portions 101c, 102c. The vertical axis of the graph shown in FIG. 6 indicates the surface roughness [Ra μm]. The surface roughness [Ra μm] is the arithmetic mean roughness based on the provisions of "JIS B 0601 (1994) and JIS B 0031 (1994)".

[0081] Fig. 7 is a graph showing the peel strength of the partitions 101, 102 against the sealing resins 61u, 61v, 61w when the surface roughness of the partitions 101, 102 is set to the size shown in Fig. 6. "Untreated" shown in Fig. 7 is the same as "untreated" shown in Fig. 6, and "roughness processing" shown in Fig. 7 is the same as "roughness processing" shown in Fig. 6, so their explanations are omitted. The vertical axis of the graph shown in Fig. 7 shows peel strength [MPa].

[0082] As shown in Non-Patent Document 1, the peel strength result of the pudding cup test is related to both the normal stress and the shear stress on the surface of the plate, and is useful as an index for evaluating the bonding strength of the interface between the sealing resin and the plate. The peel strength in this embodiment was measured by the pudding cup test. The pudding cup test is a test in which a pudding-shaped resin is directly molded on a plate, the resin is pressed with a constant force in the lateral direction (one direction within the plane of the surface of the plate to which the resin is bonded), and the force (adhesion force) applied until the resin is peeled off from the plate is measured. The pudding cup test makes it possible to measure the peel strength of the partition against the sealing resin. The greater the measured force, the higher the peel strength (i.e., adhesion).

[0083] As shown in FIG. 8, in this embodiment, a resin plate 92 formed of the same material as the partitions 101 and 102 and having a predetermined size (for example, a length of 11 [mm], a width of 11 [mm], and a thickness of 1.87 [mm]) and a resin 91 formed of the same material as the sealing resins 61u, 61v, and 61w and having a predetermined size (a bottom diameter of 3.75 [mm] that contacts the resin plate 92, a top diameter of 3 [mm], and a height of 4 [mm]) are used, and a plunger 93 is pressed against the resin 91 to apply a force to the resin 91 in the direction shown by the thick arrow in FIG. 8, to perform a test. At that time, two resin plates 92 are prepared. One surface of the two resin plates 92 is formed to have a surface roughness shown in "untreated" in FIG. 7, and the other surface of the two resin plates 92 is formed to have a surface roughness shown in "roughened" in FIG. 7.

[0084] 6, the surface roughness of the second surface portions 101d, 102d is, for example, 0.3, and the surface roughness of the first surface portions 101c, 102c is, for example, 1.43. Therefore, it is preferable that the first surface portions 101c, 102c have a surface roughness that is five times or more greater than that of the second surface portions 101d, 102d.

[0085] 7, when the surface roughness of the second surface portions 101d, 102d is, for example, 0.3, the peel strength of the second surface portions 101d, 102d against the sealing resins 61v, 61w is, for example, 26 [MPa]. On the other hand, when the surface roughness of the first surface portions 101c, 102c is, for example, 1.43, the peel strength of the second surface portions 101d, 102d against the sealing resins 61v, 61w is, for example, 31 [MPa]. In this way, by increasing the surface roughness of the partition portions 101, 102, the peel strength against the sealing resins 61u, 61v, 61w can be increased.

[0086] As described above, the semiconductor module 1 according to the present embodiment includes an outer frame 103 that defines a space 11 in which a plurality of semiconductor elements Sua, Sub, Sva, Svb, Swa, and Swb are arranged, sealing resins 61u, 61v, and 61w that are formed in the space 11 to cover the plurality of semiconductor elements Sua to Swb, and gate signal output terminals 31ua, 31ub, 31va, and 31x that are connected to the semiconductor elements Sua to Swb and output gate pulse signals that control the semiconductor elements Sua to Swb. The semiconductor elements Sua to Swb are connected to gate signal output terminals 31ua to 31wb and reference signal output terminals 32ua, 32ub, 32va, 32vb, 32wa, 32wb from which reference signals are output, and partition sections 101, 102 are arranged on the outer frame 103 to separate the space 11 into a plurality of storage sections 111u, 111v, 111w. The partition portions 101, 102 have first surface portions 101c, 102c on the side where the connection portions 311, 321 are arranged, and second surface portions 101d, 102d on the side where the connection portions 311, 321 are not arranged, and are formed so as to have a lower peel strength against the sealing resins 61u, 61v, 61w than the first surface portions 101c, 102c.

[0087] The semiconductor module 1 is intentionally provided with second surface portions 101d, 102d having a relatively low peel strength as regions for releasing tensile stress generated in the partition portions 101, 102. The semiconductor module 1 can prevent peeling of the sealing resins 61u, 61v on the sides where the connection portions 311, 321 used for connection with the semiconductor elements Sua to Swb are arranged (i.e., the first surface portions 101c, 102c of the partition portions 101, 102).

[0088] (Modification) A semiconductor module according to a modification of this embodiment will be described with reference to FIGS. In the semiconductor module 1 according to this modification, the partition 101 has a release agent formed on the second surface portion 101d. That is, the partition 101 may have a release agent formed on the region indicated by the thick dashed line in FIG. 5. On the other hand, the release agent is not formed on the first surface portion 101c of the partition 101, and the first surface portion 101c is not roughened. As a result, as indicated by the thick arrow in FIG. 2, when the semiconductor module 1 is deformed in the forward warping direction and a tensile stress is generated in the partition 101, the sealing resin 61v is easily peeled off from the second surface portion 101d. By peeling off the sealing resin 61v from the second surface portion 101d, the tensile stress applied from the sealing resin 61u to the first surface portion 101c is reduced to a level at which the wire 150 is not cut. As a result, the semiconductor module 1 can prevent the wire 150 connected to the connection portions 311 and 321 exposed to the partition 101 from being cut.

[0089] Furthermore, in the semiconductor module 1 according to this modification, the partition 102 has a release agent formed on the second surface portion 102d. This makes it possible for the semiconductor module 1 to prevent the wires 150 connected to the connection portions 311, 321 exposed at the partition 102 from being cut.

[0090] In this way, the semiconductor module 1 according to this modified example can prevent peeling of the sealing resins 61u, 61v on the side where the connection portions 311, 321 used for connecting to the semiconductor elements Sua to Swb are arranged (i.e., the first surface portions 101c, 102c of the partition portions 101, 102).

[0091] The present invention is not limited to the above-described embodiment, and various modifications are possible. The partitions 101, 102 provided in the semiconductor module 1 are formed so that the first surface portions 101c, 101c have a larger surface roughness than the second surface portions 101d, 102d, and may have a release agent formed on the second surface portions 101d, 102d. This allows the semiconductor module 1 to obtain the same effects as the semiconductor module 1 according to the above embodiment.

[0092] In the above embodiment, the transistors provided in the semiconductor elements are constituted by IGBTs, but may be constituted by wide band gap semiconductor elements.

[0093] The scope of the present invention is not limited to the exemplary embodiments shown and described, but includes all embodiments that achieve the same effect as the object of the present invention. Furthermore, the scope of the present invention is not limited to the combination of the features of the invention defined by the claims, but may be defined by any desired combination of specific features among all the respective features disclosed. [Explanation of symbols]

[0094] 1 Semiconductor module 10 Cases 11 Space 14u, 14v, 14w laminate board 15u, 15v, 15w inverter circuit 16 Cooler 21u, 21v, 21w power input terminal 31ua, 31ub, 31va, 31vb, 31wa, 31wb Gate signal output terminal 32ua,32ub,32va,32vb,32wa,32wb Reference signal output terminal 41 Positive electrode pattern 42 Negative electrode pattern 43 Output section pattern 61u,61v,61w Sealing resin 81u, 81v, 81w power output terminal 101,102 Partition 101a,102a base 101b,102b Wall part 101c,102c First surface part 101d,102d Second surface part 103 Outer Frame 103a Terminal placement area 111u, 111v, 111w storage section 141 Insulating Substrate 142 Heat transfer materials 150 Wire 211 Positive terminal 212 Negative terminal 311,321 Connection 312,322 Input section Sua, Sub, Sva, Svb, Swa, Swb Semiconductor elements

Claims

1. an outer frame defining a space in which a plurality of semiconductor elements are arranged; a sealing resin formed in the space to cover the semiconductor elements; a control terminal connected to the semiconductor element and outputting a control signal for controlling the semiconductor element; a partition section in which the control terminal is arranged with the connection section with the semiconductor element exposed and which is stretched across the outer frame to partition the space into a plurality of regions; Equipped with The partition portion has a first surface portion on a side where the connecting portion is arranged, and a second surface portion on a side where the connecting portion is not arranged, the second surface portion being formed so as to have a lower peel strength against the sealing resin than the first surface portion. Semiconductor module.

2. The first surface portion is formed to have a surface roughness greater than that of the second surface portion. The semiconductor module according to claim 1 .

3. The first surface portion has a surface roughness that is at least 5 times that of the second surface portion. The semiconductor module according to claim 2 .

4. The partition has a release agent formed on the second surface. The semiconductor module according to claim 1 .

5. the semiconductor element and the control terminal are connected by wire bonding; The connection portion is a joint between the semiconductor element and a wire. The semiconductor module according to claim 1 .

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