Electric power converter and mounting structure of semiconductor device

An electric power converter has a main circuit section including a semiconductor module and a cooling device; a control circuit substrate section electrically connected to a signal terminal of the semiconductor module, and having a control circuit; and a power wiring section connected to a main electrode terminal of the semiconductor module. The main circuit section is interposed between the control circuit substrate section and the power wiring section.

FIELD OF THE INVENTION

The present invention relates to an electric power converter such as an inverter device using a semiconductor module, and the mounting structure of a semiconductor device suitably used in the semiconductor device used as the inverter device.

BACKGROUND ART

For example, an inverter of large capacity for performing bidirectional conversion between direct current electric power and alternating current electric power is required in a hybrid automotive vehicle having both an internal combustion engine and an electric motor as a driving source, an automotive vehicle having an electric motor as a driving source, and the like. Therefore, electric power converters including this inverter have been variously developed.

An inverter circuit (i.e., an electric power converting circuit) is constructed by using a semiconductor module including an IGBT element and the like therein. However, since the inverter circuit has large capacity as mentioned above, a generating heat amount is also large. Therefore, as shown inFIG. 6, the conventional electric power converter9is constructed by assembling a cooling device91for cooling the above semiconductor module92.

More concretely, the semiconductor module92is arranged so as to face the cooling device91. A power wiring section93for supplying an electric current of a bus bar, etc. to the semiconductor module92and stopping the supply of the electric current is arranged so as to face the semiconductor module92. Further, the electric power converter9is constructed by arranging a control circuit substrate section95through a shield layer94. The control circuit substrate section95controls the operation of the semiconductor module92. However, it is indispensable that the above shield layer94is interposed and arranged to avoid the influence of noises from the above power wiring section93. For example, the structure of such an electric power converter is shown in JP-A-H11-69774.

However, there are the following problems in the conventional electric power converter9. Namely, it is indispensable in the above conventional electric power converter9that the above shield layer94is interposed and arranged to raise the operating performance of the control circuit substrate section95. Therefore, the number of parts is increased and it is difficult to cope with an entire cost reducing request.

Further, the influence of noises from the power wiring section93to the control circuit substrate section95can be reduced by the existence of the above shield layer94. However, a connecting line955for connecting the control circuit substrate section95and the semiconductor module92still becomes a structure penetrating portions of the shield layer94and the power wiring section93. Therefore, it is difficult to remove the influence of the noises on the above control circuit substrate section95.

Further, for example, in the electric automotive vehicle and the hybrid automotive vehicle, as shown inFIG. 25, the direct current of a battery1500is converted into an alternating current by an inverter device1510, and an alternating current generator1505is operated. The inverter device1510includes plural semiconductor modules.

As is well known, each semiconductor module has an internal semiconductor element (switch element)1511, a pair of electrodes on both sides of the semiconductor element1511, and a signal terminal connected to an external control circuit. The semiconductor element1511is switched by a control signal inputted from the control circuit1512through the signal terminal, and an artificial alternating current is generated.

At an operating time of the semiconductor module, noises of high frequencies are generated in its electrically conductive portion and are emitted from direct current power lines1514,1515and an alternating current power line1516. To prevent this, high frequency capacitors1521,1522and1523are connected between the direct current power lines1514,1515and the ground and between the alternating current power line1516and the ground through a lead wire1526so that a noise component is bypassed.

On the other hand, a conventional self-exited type rectifying circuit (see JP-A-07-308070) shown inFIG. 26includes self-excited type rectifying circuit portions1532and1535for converting an alternating current supplied from a commercial electric power source1530into a predetermined desirable direct current voltage. Noises generated by a switching operation of a rectifying element1536constituting the rectifying circuit portion1535are flowed into the commercial electric power source1530and have a bad influence.

To prevent this, a noise restraining circuit1540is arranged between the self-excited type rectifying circuit portions1532and1535. The noise restraining circuit1540includes a noise restraining reactor1542arranged in each phase line1541, a capacitor1544arranged between the respective phase lines1541, and a capacitor1546arranged between one phase line and the ground. The noise restraining reactor1542and the capacitor1544restrain the emission of a normal mode noise, and the capacitor1546restrains the emission of a common mode noise.

The above inverter device1510of the electric automotive vehicle, etc. has the following problems. The lead wire1526for connecting the high frequency capacitors1521to1523to the electric power lines1514to1516has a large resistance component and a large inductance component. It is necessary to increase the capacities of the high frequency capacitors1521to1523to obtain a sufficient noise restraining effect by reducing the impedance of a bypass path. Thus, a high frequency electric current transmitted via the high frequency capacitors1521to1523becomes a leaked electric current, and there is a fear that this leaked electric current becomes a factor of an error in the operation of the inverter device1510.

Further, since the semiconductor module as a noise generating source and the high frequency capacitors1521to1523for bypassing noises are separated from each other, the noises are inevitably emitted to a certain extent from the electric power lines1514to1516between the semiconductor module and the high frequency capacitors1521to1523.

On the other hand, with respect to the above self-excited type rectifying circuit, only the arrangement of the reactor1542with respect to each phase line1541, and the capacitor1544between the respective phase lines1541, etc. are shown. No concrete mounting method of the capacitors1544,1546is shown. In any case, if the capacitors1544,1546are arranged, cost and a space are correspondingly increased. Further, a resistance component, etc. exist in the lead wire for connecting the capacitors1544,1546to the phase line1541. Further, the capacitors1544,1546are separated from the rectifying circuit portion1535so that noises are easily emitted from the phase line1541between the capacitors1544,1546and the rectifying circuit portion1535.

The present invention is made in consideration of such conventional problems, and a first object of the present invention is to provide an electric power converter capable of reducing the number of parts and restraining the influence of noises from the power wiring section. A second object of the present invention is to provide the mounting structure of a semiconductor device capable of effectively restraining the emission of noises generated in the semiconductor element without externally attaching a special bypass capacitor.

DISCLOSURE OF THE INVENTION

To achieve the above first object, an electric power converter in the present invention comprises:

a main circuit section including a semiconductor module constituting one portion of an electric power converting circuit, and a cooling device for cooling the semiconductor module;

a control circuit substrate section electrically connected to a signal terminal of said semiconductor module, and having a control circuit for controlling the operation of said semiconductor module; and

a power wiring section connected to a main electrode terminal of said semiconductor module, and supplying an electric current to said semiconductor module and stopping the supply of the electric current;

wherein said main circuit section is interposed between said control circuit substrate section and said power wiring section.

As mentioned above, the electric power converter of the present invention is arranged such that the main circuit section constructed by the semiconductor module and its cooling device is nipped and supported by the above control circuit substrate section and the power wiring section. Therefore, the above main circuit section functions as a shield portion between the above control circuit substrate section and the power wiring section, and can restrain that electric noises from the power wiring section are transmitted to the control circuit substrate section. Thus, a shield layer conventionally required can be set to be unnecessary, and the number of parts can be reduced.

Further, since the above main circuit section and the above control circuit substrate section are adjacently arranged, the electric joining portion between the main circuit section and the control circuit substrate section can be arranged in a boundary portion of both the main circuit section and the control circuit substrate section, and it is not necessary to penetrate the above power wiring section. Therefore, it is further possible to restrain the influence of the electric noises from the power wiring section to the control circuit substrate section. Thus, in accordance with the present invention, it is possible to provide an electric power converter capable of reducing the number of parts and restraining the influence of the noises from the power wiring section.

Further, to achieve the above second object, the mounting structure of a semiconductor device in the present invention is characterized in that a bypass capacitor is formed as a dielectric member by interposing one portion of a semiconductor module, one portion of a holding member or a separate mediating member between a semiconductor element of the semiconductor module and the holding member for holding the semiconductor module from both sides, or between the semiconductor element and a case for storing the semiconductor module.

Namely, a first mounting structure of the semiconductor device in the present invention is constructed by a semiconductor module and electrically conductive first and second holding members for holding the semiconductor module from both sides through a first insulating member and a second insulating member as dielectrics. The semiconductor module includes a semiconductor element for electric power; a first electrode plate and a second electrode plate respectively joined to one face and the other face of the semiconductor element; a connecting terminal with a control circuit for controlling the operation of the semiconductor element; and a resin mold of an insulating property for sealing the semiconductor element, the first electrode plate and the second electrode plate.

In accordance with the above mounting structure, noises generated at an operating time of the semiconductor module are absorbed by a bypass capacitor for noise restraint constructed by the first electrode plate and/or the second electrode plate, the first holding member and/or the second holding member, and the first insulating member and/or the second insulating member located between the electrode plates and the holding members, and their emission to an electric power line, etc. is prevented. Namely, the emission of the noises generated in the semiconductor element for electric power is restrained by the bypass capacitor for noise restraint in which the insulating members located between the electrode plates and the holding members are set to a dielectric. As its result, a dedicated bypass capacitor for restraining the noise emission is not required, and labor and time for externally attaching this bypass capacitor are not required so that cost is reduced.

Since the bypass capacitor is arranged near the semiconductor element and arranged by each semiconductor element, the restraining effect of the emitted noises is reliable and effective. Further, since the holding members are electrically conductive, its grounding is easy.

In the above mounting structure, it is preferable that one portion of the first electrode plate and the second electrode plate is exposed, and the first insulating member and the second insulating member are plates of the insulating property interposed between the exposure portion of the first electrode plate and the second electrode plate and the first holding member and the second holding member. In accordance with this mounting structure, the plate of the insulating property interposed between the semiconductor module and the electrically conductive holding member becomes a dielectric member. Accordingly, the general-purpose semiconductor module and holding pipe can be used as they are, and a rise in cost can be restrained at its minimum.

In the above mounting structure, it is preferable that one portion of the first electrode plate and the second electrode plate is exposed, and the first insulating member and the second insulating member are films of the insulating property integrated with a resin mold and covering the exposure portion of the first electrode plate and the second electrode plate. In accordance with this mounting structure, the films of the insulating property integrated with the resin mold of the semiconductor module become a dielectric member. Further, one portion of the first electrode plate and the second electrode plate may be exposed, and the first insulating member and the second insulating member may be also a film of the insulating property integrated with the first holding member and the second holding member so as to be opposed to the exposure portion. In accordance with this mounting structure, the film of the insulating property integrated with a holding pipe becomes a dielectric member. Accordingly, the bypass capacitor can be easily formed only by slightly improving the general-purpose semiconductor module and holding pipe in any case.

In the above mounting structure, the first holding member and the second holding member are preferably connected to the ground. When the holding members are thus connected to the ground, the restriction of noises due to the bypass capacitor is more reliable. Further, a structure for circulating an electrically conductive cooling medium into the first holding member and the second holding member and connecting this cooling medium to the ground may be also used. In this case, the cooling medium originally used as a cooling means of the semiconductor element can be utilized as a grounding means so that noises can be more reliably restrained.

Namely, a second mounting structure of the semiconductor device in the present invention is constructed by a semiconductor module and a first holding member and a second holding member of the insulating property for inserting electrically conductive first and second internal members thereinto and holding the semiconductor module from both sides and becoming a dielectric member. The semiconductor module includes a semiconductor element for electric power; a first electrode plate and a second electrode plate respectively joined to one face and the other face of the semiconductor element; a connecting terminal with a control circuit for controlling the operation of the semiconductor element; and a resin mold of the insulating property for sealing the semiconductor element, the first electrode plate and the second electrode plate.

In accordance with the above mounting structure, noises generated at an operating time of the semiconductor module are absorbed by a bypass capacitor for noise restraint constructed by the first electrode plate and/or the second electrode plate, the first internal member and/or the second internal member, and wall portions of the first holding member and/or the second holding member located between the electrode plates and the internal members, and their emission to an electric power line, etc. is prevented. As its result, a dedicated bypass capacitor for restraining the noise emission is not required, and labor and time for externally attaching this bypass capacitor are not required so that cost is reduced. Since the bypass capacitor is arranged near the semiconductor element and arranged by each semiconductor element, the restraining effect of the emitted noises is reliable and effective. Further, since the holding members have the insulating property, the width of a selection of materials is widened and some materials are lightened in weight.

In the above mounting structure, the first internal member and the second internal member are preferably connected to the ground. Further, the first internal member and the second internal member may also have a structure for circulating an electrically conductive cooling medium to the first internal member and the second internal member and grounding this cooling medium. In any case, noises due to the bypass capacitor can be more reliably restrained.

Further, a third mounting structure of the semiconductor device in the present invention is constructed by a semiconductor module and a case for storing an electrically conductive cooling medium and closely arranging plural semiconductor modules within the cooling medium and manufactured by a metal. The semiconductor module includes a semiconductor element for electric power; a first electrode plate and a second electrode plate respectively joined to one face and the other face of the semiconductor element; a connecting terminal with a control circuit for controlling the operation of the semiconductor element; and a resin mold of an insulating property for sealing the semiconductor element, the first electrode plate and the second electrode plate.

In accordance with the above mounting structure, noises generated at the operating time of the semiconductor module are absorbed by a bypass capacitor for noise restraint constructed by the first electrode plate and/or the second electrode plate, the cooling medium, the first mold portion and/or the second mold portion of the resin mold located between the electrode plates and the cooling medium, and their emission to an electric power line, etc. is prevented. Namely, the emission of the noises generated in the semiconductor element for electric power is restrained by the bypass capacitor for noise restraint in which the mold portions of the resin mold located between the electrode plates and the cooling medium are set to a dielectric member. As its result, a dedicated bypass capacitor for restraining the noise emission is not required, and labor and time for externally attaching this bypass capacitor are not required so that cost is reduced.

Since the bypass capacitor is arranged near the semiconductor element and arranged by each semiconductor element, the restraining effect of the emitted noises is reliable and effective. Further, since the case for storing the cooling medium also functions as a positioning means of the semiconductor module, no holding member is required and the number of parts can be reduced and an assembly process can be simplified.

In the above mounting structure, the cooling medium is preferably connected to the ground. Thus, the restraining effect of the emitted noises due to the bypass capacitor becomes more reliable.

PREFERRED EMBODIMENTS OF THE INVENTION

1. Electric Power Converter

First, the summary of an electric power converter will be explained. In the electric power converting circuit, for example, a power wiring section is constructed by a bus bar connected to a three-phase motor, etc., a connecting portion of the bus bar, etc. and a main electrode terminal of a semiconductor module, etc. In the power wiring section, an electric current to be controlled is inputted to the semiconductor module, and is outputted from the semiconductor module.

A control circuit substrate section is a section connected to a signal terminal of the semiconductor module, and having a control circuit for sending a control signal to the semiconductor module. A main circuit section is constructed by including the semiconductor module and a cooling device for cooling this semiconductor module.

A structure constructed by using a semiconductor element of one kind of or plural semiconductor elements and having the main electrode terminal and the signal terminal is used as the semiconductor module. As described later, this semiconductor module is preferably of a both-sides cooling type. Namely, the semiconductor module preferably has a structure able to cool the semiconductor module from one face and another face opposed to this one face.

An electronic part connected to the semiconductor module is preferably arranged together in the power wiring section. Namely, there is a case in which the electronic part itself, or the bus bar connected to this electronic part emits an electric noise. Accordingly, it is preferable to arrange the electronic part in the power wiring section. Thus, it is possible to restrain the influence of the electric noise from the electronic part to the control circuit substrate section. For example, there are parts such as a reactor, a capacitor, etc. as the electronic part. A voltage raising circuit is constructed by these electronic parts.

The semiconductor module is constructed by a module main body portion for building-in a semiconductor part, a main electrode terminal projected from this module main body portion, and a signal terminal projected in a direction different by about 180 degrees from the projecting direction of the main electrode terminal. The cooling device has a pair of refrigerant tubes arranged so as to nip and support the module main body portion from both sides. The module main body portion is constructed so as to be cooled from both sides by circulating a cooling medium into the refrigerant tube. The semiconductor module is preferably arranged such that the main electrode terminal and the signal terminal are respectively projected in directions different from each other and approximately perpendicular to the longitudinal direction of the pair of refrigerant tubes.

In this case, the semiconductor module and the refrigerant tube can be arranged in parallel with each other, and the main electrode terminal and the signal terminal can be respectively arranged in different directions perpendicular to this arranging direction. Therefore, the control circuit substrate section and the power wiring section can be very easily distributed and arranged on both sides of the main circuit section in which the semiconductor module and the refrigerant tube are arranged.

The main circuit section has a laminating structure in which plural refrigerant tubes and plural semiconductor modules are alternately laminated. The main electrode terminal of the semiconductor module is preferably projected from one face in a direction perpendicular to this laminating direction, and the signal terminal is also preferably projected from its opposite face. In this case, the laminating structural body of the semiconductor module and the refrigerant tube is easily integrated as one unit so that the entire main circuit section can be made compact and can be easily treated in manufacture.

In the arrangement of the semiconductor module and the refrigerant tube, it is also possible to adopt an arranging method in which two refrigerant tubes as one set for nipping and supporting the semiconductor module in one line are set to one unit and this unit is repeatedly arranged. In this case, plural units each constructed by this one unit are manufactured and are arranged in parallel. The plural refrigerant tubes are connected by a pair of header portions so that the entire structure can be formed as a unit.

First Embodiment

An electric power converter in accordance with a first embodiment of the present invention will next be explained by usingFIGS. 1 to 4. An electric power converter1according to the first embodiment is an electric power converter for a hybrid automotive vehicle. As shown inFIG. 1, the electric power converter1is constructed by a main circuit section10, a control circuit substrate section2and a power wiring section3. The main circuit section10is interposed between the control circuit substrate section2and the power wiring section3.

As shown inFIGS. 2 and 3A,3B,3C, the main circuit section10is constructed by including a semiconductor module4constituting one portion of the electric power converting circuit, and a cooling device5for cooling this semiconductor module4. The control circuit substrate section2is a substrate electrically connected to a signal terminal42of the semiconductor module4, and having an unillustrated control circuit for controlling the operation of the semiconductor module4. The power wiring section3is a section connected to a main electrode terminal41of the semiconductor module4and supplying an electric current to the semiconductor module4and stopping the supply of the electric current.

In the first embodiment, as shown inFIGS. 2 and 3B, the semiconductor module4is constructed by a module main body portion40building-in a semiconductor element, the main electrode terminal41projected from the module main body portion40, and the signal terminal42projected in a direction different by about 180 degrees from the projecting direction of the main electrode terminal41. In the module main body portion40, a heat radiating plate451connected to the main electrode terminal41is exposed to both main faces401and402of this module main body portion40.

As shown inFIG. 3B, the cooling device5has a pair of refrigerant tubes51arranged so as to nip and support the module main body portion40from both faces. In this example, two semiconductor modules4are nipped and supported in parallel between the pair of refrigerant tubes51. The main circuit section10is entirely constructed by alternately laminating the refrigerant tube51and a line of the semiconductor module4. Thus, all the semiconductor modules4attain a state in which both the faces401and402of the semiconductor modules4are nipped and supported by the refrigerant tube51.

Each refrigerant tube51has an unillustrated refrigerant passage in its interior, and is constructed so as to circulate a cooling medium to this refrigerant passage. As shown inFIG. 3B, a bellows pipe59is arranged so as to respectively connect both ends of the plural refrigerant tubes51so that a header portion50is formed. The module main body portion40is cooled from both the faces401and402by circulating the cooling medium into the refrigerant tube51. Each semiconductor module4is arranged such that the main electrode terminal41and the signal terminal42are respectively projected in directions different from each other and approximately perpendicular to the longitudinal direction of the pair of refrigerant tubes51. Thus, the control circuit substrate section2and the power wiring section3are very easily distributed and arranged on both faces of the main circuit section10in which the semiconductor module4and the refrigerant tube51are arranged.

As shown inFIG. 3C, the control circuit substrate section2has plural connecting holes22for inserting and arranging the signal terminal42of the semiconductor module4. The control circuit substrate section2is constructed such that the control circuit and the signal terminal42are electrically connected by inserting the signal terminal42into this connecting hole22. A support bar29rising in the control circuit substrate section2abuts on the refrigerant tube51of the main circuit section10, and functions as a spacer for constantly holding the distance between the main circuit section10and the control circuit substrate section2.

As shown inFIG. 3A, the power wiring section3is constructed by plural bus bars31connected to an unillustrated three-phase motor, and a resin mold portion30for molding one portion of these bus bars31. Plural unillustrated joining terminal portions joined to the main electrode terminal41of the semiconductor module4are arranged on a face302facing the main circuit section10of the power wiring section3.

As shown inFIGS. 3A,3B,3C and4, the power wiring section3is adjacently arranged above the main circuit section10, and the control circuit substrate section2is adjacently arranged below the main circuit section10. The main electrode terminal41of the semiconductor module4and the power wiring section3are electrically connected, and the signal terminal42is electrically joined to the control circuit substrate section2so that the electric power converter1of this example is obtained.

As mentioned above, the electric power converter1of this example is arranged such that the main circuit section10constructed by the semiconductor module4and its cooling device5is nipped and supported by the control circuit substrate section2and the power wiring section3. Therefore, the main circuit section10functions as a shield portion between the control circuit substrate section2and the power wiring section3, and it is possible to restrain that electric noises from the power wiring section3are transmitted to the control circuit substrate section2. Thus, a shield layer conventionally required can be set to be unnecessary so that the number of parts can be reduced.

Since the main circuit section10and the control circuit substrate section2are adjacently arranged, the electric joining portion between both the main circuit section10and the control circuit substrate section2can be arranged in a boundary portion of both the main circuit section10and the control circuit substrate section2, and it is not necessary to penetrate the power wiring section3. Therefore, the influence of electric noises from the power wiring section3to the control circuit substrate section2can be further restrained.

Further, this example adopts a structure in which both faces can be cooled and the main electrode terminal41and the signal terminal42are projected in directions different from each other by about 180 degrees as the semiconductor module4. This structure is utilized at its maximum, and the laminating structure with the refrigerant tube51is realized as mentioned above. Further, the structure for respectively projecting the main electrode terminal41and the signal terminal42in different directions perpendicular to this laminating direction is set. Thus, the improvement of cooling efficiency of the semiconductor module4, and the realization of the structure for distributing and arranging the control circuit substrate section2and the power wiring section3on both the faces of the main circuit section10have been able to be easily achieved.

This example is set to the structure in which the main circuit section10is arranged above the control circuit substrate section2, and the power wiring section3is arranged further above the main circuit section10. However, while this relative relation is maintained as it is, it is possible to change this arrangement into a mode for reversely rotating the vertical direction, or a mode inverted by 90 degrees, etc.

Second Embodiment

As shown inFIG. 5, a second embodiment is an example in which a reactor61and a capacitor62constituting one portion of a voltage raising circuit are arranged in the power wiring section3of the electric power converter1on the basis of the electric power converter1according to the first embodiment. In this case, it is possible to restrain the influence of electric noises from the reactor61and the capacitor62as electronic parts constituting the voltage raising circuit to the control circuit substrate section3. With respect to the others, operations and effects similar to those in the first embodiment are obtained.

2. Mounting Structure

Next, the second embodiment of the mounting structure of a semiconductor device in the present invention will be explained. This mounting structure of the semiconductor device can be classified into the following three types in accordance with a forming method of a bypass capacitor for noise restraint, particularly, whether what becomes a dielectric (insulator) member.

(1) In a first type, a plate and a film of an insulating property interposed between a semiconductor module and a holding member for holding or nipping and supporting this semiconductor module from both the front and rear sides become the dielectric member, and various modes are included. In a first mode, an electrode plate of the semiconductor module is partially exposed from a resin mold of the semiconductor module so as to form one electrode plate. The holding member is constructed by an electrically conductive material so as to form the other electrode plate.

It is desirable to connect the bypass capacitor to both a first electrode plate of the front face side of the semiconductor module and a second electrode plate of the rear face side. However, such a construction is not indispensable, and the bypass capacitor may be also connected to only the first or second electrode plate. To make this connection, a plate of the insulating property, etc. may be interposed only between one electrode plate and the holding member opposed to this one electrode plate. This construction is similarly used in second to fourth modes of the first type, and second and third types described later.

In the second mode, one portion (mold portion) of a resin mold for covering the electrode plate of the semiconductor module becomes the dielectric member. In the third mode, one portion of the exposed electrode plate of the semiconductor module is covered with a film of an insulating property integrated with a resin module, and this film becomes the dielectric member. In the fourth mode, a film of the insulating property integrated with the holding member and opposed to one portion of the exposed electrode plate of the semiconductor module becomes the dielectric member.

In any mode, it is desirable to circulate the cooling medium into the interior of the holding member. The cooling medium restrains a rise in temperature of the semiconductor module, and is also effective to connect the holding member to a vehicle body as the ground in an electrically conductive case.

(2) In the second type, the holding member for holding or nipping and supporting the semiconductor module from both the front and rear sides becomes the dielectric member or the other electrode plate. Therefore, the holding member is constructed by an insulating material, and an electrically conductive internal member is inserted into this holding member. The electrode plate of the semiconductor module is partially exposed. The cooling medium can be circulated into the holding member.

(3) The third type includes no holding member for holding the semiconductor module from both the front and rear sides, etc. One electrode plate and the dielectric member are formed in the semiconductor module, and the other electrode plate is the electrically conductive cooling medium stored to a case manufactured by a metal. The electrode plate of the semiconductor module is covered with one portion (mold portion) of the resin mold. Plural semiconductor modules are positioned by the case in a predetermined state.

Each type and the mode in each type will next be explained with reference to the accompanying drawings.

Third Embodiment

A driving system of a hybrid automotive vehicle shown inFIG. 7includes a battery1010, an motor generator (MG)1020and an inverter device1060. A smoothing capacitor1013and a semiconductor pair for a three-phase alternating current (U-phase, V-phase and W-phase) constituting the inverter device1060are arranged between direct current bus bars1011and1012extended from a positive electrode terminal and a negative electrode terminal of the battery1010. A U-phase line1016is extended to MG1020from between first and second U-phase semiconductor elements1031and1032.

A V-phase line1017is extended to MG1020from between first and second V-phase semiconductor elements1031and1032. A W-phase line1018is extended to MG1020from between first and second W-phase semiconductor elements1031and1032.

As shown inFIGS. 8 to 10, the inverter device1060is constructed by alternately laminating a holding pipe1055and plural semiconductor modules1030through an insulating material1050in the height direction. As shown inFIGS. 11 to 13Aand13B, each semiconductor module1030includes a first semiconductor element (IGBT)1031and a second semiconductor element (fly wheel diode)1032, a first electrode plate1035joined to these front face sides through solders1033a,1033b, and a second electrode plate1036joined to these substrate sides (rear face sides) through unillustrated solder.

A first driving electrode terminal1038and a second driving electrode terminal1039are respectively integrated with the first electrode plate1035and the second electrode plate1036. A control electrode terminal1041is joined to the first semiconductor element1031by a signal line of a bonding wire1042, etc. The control electrode terminal1041includes a gate terminal (G) and an emitter terminal (Ke) for turning the first semiconductor element1031on and off, an output terminal (K, A) of a temperature diode formed on the surface of the first semiconductor element1031and detecting its temperature, and an electric current detecting terminal (Se) for detecting an electric current flowed to the first semiconductor element1031.

The first semiconductor element1031and the second semiconductor element1032, the first electrode plate1035and the second electrode plate1036, the first driving electrode terminal1038and the second driving electrode terminal1039, the control terminal1041, etc. are sealed by a resin mold1045. The resin mold1045is filled between the first electrode plate1035and the second electrode plate1036, and secures the insulation between both the electrode plates1035and1036. The resin mold1045also fixedly attaches the connecting terminal1041, and secures the insulation between the first electrode plate1035, the second electrode plate1036and the connecting terminal1041. The rear faces of the first electrode plate1035and the second electrode plate1036are exposed. The semiconductor module1030has a flat rectangular shape.

It is returned toFIGS. 8 to 10, and the insulating material1050is constructed by a plate and a film of e.g., aluminum nitride and silicon nitride, and has a rectangular shape slightly greater than that of the semiconductor module1030. The holding pipe (nipping and supporting pipe)1055is molded by an extrusion molding method of aluminum, etc., and has an air gap portion1056apartitioned by a fin1056band extended in the longitudinal direction. The holding pipe1055has a width slightly greater than the widths of the electrode plates1035,1036of the semiconductor module1030, and also has a length able to arrange plural semiconductor modules1030on this holding pipe1055. The air gap portion1056ais penetrated in the longitudinal direction, and the electrically conductive cooling medium is circulated into the air gap portion1056a.

Here, an assembly body of the plural semiconductor modules1030arranged in parallel, an upper (first) holding pipe1055A of its front face side, a lower (second) holding pipe1055B of its rear face side will be considered. The upper holding pipe1055A is opposed to the first electrode plate1035through a first insulating plate1050A, and the lower holding pipe1055B is opposed to the second electrode plate1036through a second insulating plate1050B.

The first driving electrode terminal1038and the second driving electrode terminal1039are projected onto one side of the upper holding pipe1055A and the lower holding pipe1055B, and are respectively connected to a positive direct current bus bar1011and a negative direct current bus bar1012, and alternating current bus bars1016to1018connected to MG1020. The control electrode terminal1041is projected from the other side, and is connected to the control circuit1048. The holding pipes1055A,1055B are connected to one portion of the car body of a hybrid automotive vehicle.

As its result, the first insulating plate1050A as an electrically nonconductive material exists between the first electrode plate1035as an electrically conductive material and the first holding pipe1055A, and a first bypass capacitor1057A is formed by these three members. Similarly, a second bypass capacitor1057B is formed by the second electrode plate1036, the second holding pipe1055B, and the second insulating plate1050B existing between the second electrode plate1036and the second holding pipe1055B.

A bellows member1061is interposed between both ends of the adjacent upper holding pipe1055A and lower holding pipe1055B. Both these ends are adhered to the upper holding pipe1055A and the lower holding pipe1055B by brazing, adhesion, etc. in a state securing an air-tight property. The cooling medium is supplied from a pipe1062to this bellows member1061. Accordingly, the cooling medium is flowed to the air gap portion1056of the holding pipe1055. Thus, a circulating path of the cooling medium is formed by the pipe1062, unillustrated piping pump and radiator, etc.

A laminating body of plural holding pipes1055and plural semiconductor modules1030is stored to an unillustrated metallic case. This metallic case is fixed to the car body of the electric automotive vehicle, and is electrically conducted to this car body. The holding pipe1055is finally connected to the car body as the ground.

For example, at an advancing time, etc. after an idle stop, the direct current of the battery1010is converted into an alternating current by the inverter device1060, and operates MG1020. On the other hand, at a running time using an engine, the generated alternating current is converted into a direct current by operating MG1020, and is charged to the battery1010. Since this action itself is publicly known, a detailed explanation is omitted here.

In accordance with the third embodiment, the following effects are obtained with respect to the restraint of noises. First, it is restrained without mounting a special or dedicated bypass capacitor that noises generated in the first semiconductor element1031and the second semiconductor element1032are emitted to bus bars1011,1012,1016, etc. This is because the electrode plates1035,1036become one electrode plate, and the holding pipes1055A,1055B become the other electrode plate, and the insulating plates1050A,1050B become a dielectric member, and the bypass capacitors1057A,1057B are formed by these members.

The insulating plates1050A,1050B are originally interposed for the electric insulation of the semiconductor elements1031,1032and the holding pipes1055A,1055B, but also function as dielectrics from their nature (insulating property) and arranging positions. As its result, it is not necessary to take labor and time for connecting a dedicated bypass capacitor by a lead wire, and it is advantageous in space.

Secondly, the emitted noises are reliably restrained. This is because the capacitors1057A,1057B are respectively individually connected to the first semiconductor element1031and the second semiconductor element1032, and are located just near the first semiconductor element1031and the second semiconductor element1032as a generating source of the noises.

Thirdly, the restraining effect of the emitted noises is high for the following two reasons. First, the first holding pipe1055A and the second holding pipe1055B are connected to the body of the vehicle through an electrically conductive LLC, a pump, a radiator, etc. internally circulated. Thus, the impedance of a path for bypassing the noises of the semiconductor elements1031,1032to the vehicle body is reduced. Furthermore, the fin1056binternally formed on the inner circumferential face of the air gap portion1056aimproves the electric coupling of the holding pipe1055and the LLC.

Further, an excellent cooling effect is obtained with respect to the cooling of the first semiconductor element1031and the second semiconductor element1032is obtained. This is because a double faced cooling system for direct close attachment to the first holding pipe1055A and the second holding pipe1055B for respectively internally circulating the cooling medium through the first electrode plate1035arranged on the front face side of the semiconductor elements and the second electrode plate1036arranged on the rear face side is adopted.

Fourth Embodiment

FIGS. 14 to 17disclose a fourth embodiment. In the fourth embodiment, one portion of a resin mold1110of the semiconductor module instead of the first insulating plate1050A and the second insulating plate1050B according to the third embodiment constitutes a dielectric member.

The fourth embodiment will next be described in detail. The front face of the first electrode plate1035and the rear face of the second electrode plate1036are not exposed, but are respectively covered with a first mold portion1112and a second mold portion1113. As its result, a first bypass capacitor1115A and a second bypass capacitor1115B are formed by the first semiconductor element1031and the second semiconductor element1032, the first holding pipe1055A and the second holding pipe1055B, and the first mold portion1112and the second mold portion1113located therebetween.

In accordance with the fourth embodiment, effects similar to those in the third embodiment are obtained. In addition, the semiconductor device can be compactly constructed. This is because the first mold portion1112and the second mold portion1113have a function as an insulating material between the first and second semiconductor elements1031and1032and the first and second holding pipes1055A and1055B, and also have a function as the dielectric of the bypass capacitor. Further, the first insulating plate1050A and the second insulating plate1050B in the third embodiment are not required.

Fifth Embodiment

In a fifth embodiment shown inFIG. 18, a first insulating film1153and a second insulating film1154instead of the insulating plates1050A,1050B according to the third embodiment are closely formed in a first mold portion1151and a second mold portion1152, and cover exposure portions of the first electrode plate1035and the second electrode plate1036. For example, the first insulating film1153and the second insulating film1154are constructed by a flame spraying film of alumina, and a film of DLC (diamond like carbon). As its result, bypass capacitors1155A and1155B are constructed by the first semiconductor element1031and the second semiconductor element1032, the first holding pipe1055A and the second holding pipe1055B, and the first insulating film1153and the second insulating film1154located therebetween.

In the fifth embodiment, effects similar to those in the third embodiment are obtained. In addition, the capacities of the bypass capacitors1155A,1155B can be increased since the first insulating film1153and the second insulating film1154are located just near the first semiconductor element1031and the second semiconductor element1032.

Furthermore, the capacities can be changed if the thicknesses of the first insulating film1153and the second insulating film1154are adjusted. As is well known, the capacities of the capacitors are inversely proportional to the thicknesses of the insulating films1153,1154. Accordingly, when it is desirous to increase the capacities, the thicknesses of the insulating films1153,1154are decreased. In contrast to this, when it is desirous to decrease the capacities, the thicknesses of the insulating films1153,1154are increased. Since the capacities are proportional to the surface areas of the electrode plates1035,1036, the surface areas of the electrode plates1035,1036can be also adjusted together with the adjustment of the thicknesses of the insulating films1153,1154, or separately from this adjustment.

The first insulating film1153and the second insulating film1154may be also formed in the first holding pipe1055A and the second holding pipe1055B by exposing the first electrode plate1035and the second electrode plate1036of the semiconductor module1030.

Sixth Embodiment

In an embodiment 6 shown inFIGS. 19 to 21Aand21B, a holding pipe1210constructed by an insulating material such as resin, ceramics, etc. is used instead of the holding pipe1055manufactured by a metal. An electrically conductive inner pipe1215is inserted into a hollow portion of the holding pipe1210of the insulating property, and a cooling medium is circulated in its air gap portion1216. The first electrode plate1035and the second electrode plate1036of the semiconductor module1030are exposed. Accordingly, bypass capacitors1220A and1220B are constructed by the first electrode plate1035and the second electrode plate1036, first and second inner pipes1215A and1215B, and wall portions1212A and1212B of holding pipes1210A and1210B located therebetween.

In accordance with the sixth embodiment, the insulating wall portion1212of the holding pipe1210for originally circulating the cooling medium becomes a dielectric member in addition to effects similar to those of the third embodiment. Accordingly, it is unnecessary to form the dielectric member in the semiconductor module1030, etc. Further, since no electrically conductive property is required in the holding pipe1210, the width of a selection of materials is widened.

Seventh Embodiment

FIGS. 22 to 24disclose a seventh embodiment. In the seventh embodiment, the first driving electrode terminal1038and the second driving electrode terminal1039and the control terminal1041of the semiconductor module1030are projected from the same side face. The unillustrated front face of the first electrode plate1035and the unillustrated rear face of the second electrode plate1036are covered with first and second mold portions1251,1252.

Plural openings1262are arranged on the upper end side of a case1260manufactured by a metal, and an electrically conductive cooling medium1265is filled within these openings1262. The lower end of each semiconductor module1030is dipped into the cooling medium1265of the case1260, and the upper end is projected above from the opening1262and is sealed by a seal member1263. First and second bypass capacitors1270A and1270B are formed by the first semiconductor element1031and the second semiconductor element1032, the cooling medium1265, and the mold portions1251,1252located therebetween.

In accordance with the seventh embodiment, the bypass capacitors1270A and1270B are formed near the first semiconductor element1031and the second semiconductor element1032every first and second semiconductor elements1031and1032, and noises are effectively restrained. In addition, the case1260manufactured by a metal and storing the cooling medium1265positions the plural semiconductor modules1030in a predetermined state. Each semiconductor module1030can be set to the predetermined state only by inserting each semiconductor module1030from the opening1262of the case1260, and time for manufacturing an inverter device can be shortened.