Power electronics module and installation method

Abstract

A power electronics module and a method of installation are presented. The power electronics module has: a first circuit board having an uppermost layer, an intermediate layer, and a lowermost layer; a second circuit board having an uppermost layer, an intermediate layer, and a lowermost layer; a high-side line having a power semiconductor formed as a high-side switch; and a low-side line having a power semiconductor formed as a low-side switch, the first circuit board and the second circuit board being arranged opposite each other such that the uppermost layers face each other, the uppermost layer of the first circuit board serving as an AC coupling portion, the uppermost layer of the second circuit board being structured such that it serves as a DC negative coupling portion and a DC positive coupling portion, the power semiconductors formed as high-side switches and the power semiconductors formed as low-side switches are arranged such that their AC connections point to and are in contact with the uppermost layer of the first circuit board, and the DC connections of the power semiconductors point to and are in contact with the uppermost layer of the second circuit board.

Description

Technical Field

[0001] The present invention relates to the field of electric vehicles, in particular electronic device modules. Background Art

[0002] The use of electronic device modules, such as power electronic device modules, in motor vehicles has increased significantly in recent decades. This is due on the one hand to the need to improve fuel saving and vehicle performance, and on the other hand to the progress of semiconductor technology. In order to be able to provide energy, a large number of electronic components are required, with which, for example, bridge circuits (such as half bridges) are realized, such as semiconductor power switches, which are also called power semiconductors. The power semiconductors can be arranged in a complete power electronic device module (also called power module) or as discrete components. The power electronic device module has a circuit board and power semiconductors arranged on the circuit board, on which the power semiconductors are electrically contacted with each other for power transmission and control management.

[0003] The switched power semiconductors of electronic modules must be actively cooled in order to avoid switching losses and line losses. For simple connection of the power semiconductors, they are arranged in a two-dimensional plane, with the phase taps (AC) being arranged centrally between the power semiconductors. This arrangement results in simple manufacturability in one plane, but this results in non-optimal commutation units.

[0004] In order to increase the cooling power, some solutions have been proposed, in which cooling is also performed on the upper side of the power semiconductors 3.1, 3.2 by means of cooling bodies 5, 6, such as Figure 1 As schematically illustrated. The usual two-dimensional layout in the chip arrangement is retained here and a thermal connection of the upper structures of the power semiconductors 3.1, 3.2 is provided, thereby improving cooling. For this purpose (when using MOSFETs) a load connection must be established between the source S of the power semiconductor 3.1 serving as the high side and the drain D of the power semiconductor 3.2 serving as the low side. This can be achieved by wire bonding, such as Figure 1 As illustrated by curved lines in FIG. 1 . However, this embodiment requires space on the power semiconductor 3.1 used as the high side (which limits the heat conduction connection upwards) and on that part of the circuit board which is usually formed as a DBC circuit board 1 and serves as the phase AC (AC tap). Alternatively, the load path can be partially guided in the upper DBC circuit board 2, but for this purpose, additional components are required to achieve the connection with the lower DBC circuit board 1. An example of an electronic device module for such double-sided cooling can be found, for example, in US 10,211,133 B2.

[0005] In addition to optimizing the thermal path, optimizing the electrical performance within the power electronics module is also very important. However, the known solutions for double-sided cooled electronics modules do not reflect electrical optimization. Summary of the invention

[0006] It is therefore an object of the present invention to provide a power electronics module by means of which improved cooling of the power semiconductors, in particular double-sided cooling, and electrical optimization can be achieved.

[0007] This object is achieved by the features of the independent claim. Advantageous embodiments are the subject matter of the dependent claims.

[0008] A power electronic device module is proposed, which comprises: a first circuit board having an uppermost layer made of an electrically conductive material, a middle layer made of an electrically non-conductive material, and a lowermost layer made of an electrically conductive material; and a second circuit board having an uppermost layer made of an electrically conductive material, a middle layer made of an electrically non-conductive material, and a lowermost layer made of an electrically conductive material; and a high-side line having at least one power semiconductor formed as a high-side switch; and a low-side line having at least one power semiconductor formed as a low-side switch, wherein the first circuit board is arranged opposite to the second circuit board so that the uppermost layers face each other, and wherein the uppermost layer of the first circuit board serves as an AC phase connection, and wherein the uppermost layer of the second circuit board is structured so that it serves as a DC negative connection and a DC positive connection, and the power semiconductor formed as a high-side switch and the power semiconductor formed as a low-side switch are arranged so that their AC connections point to and are in contact with the uppermost layer of the first circuit board, and the DC connections of the power semiconductors point to and are in contact with the uppermost layer of the second circuit board.

[0009] In one embodiment, each power semiconductor is provided with a spacer element, and wherein the spacer element of the power semiconductor formed as a high-side switch is arranged between the topmost layer of the first circuit board and the power semiconductor and is in electrical and thermal contact with the first circuit board and the power semiconductor, and wherein the spacer element of the power semiconductor formed as a low-side switch is arranged between the topmost layer of the second circuit board and the power semiconductor and is in electrical and thermal contact with the second circuit board and the power semiconductor, or wherein the spacer element of the power semiconductor formed as a low-side switch is arranged between the topmost layer of the first circuit board and the power semiconductor and is in electrical and thermal contact with the first circuit board and the power semiconductor.

[0010] In one embodiment, the power electronics module further comprises at least one signal / control track for each power semiconductor, wherein at least one signal / control connection is provided on the side of each power semiconductor to be contacted with one of the DC connections, said signal / control connection being contacted with the associated signal / control track by means of a connecting element.

[0011] In one embodiment, the topmost layer of the second printed circuit board is structured such that a first partial area of ​​the topmost layer serves as a contact area for an AC track to be contacted therewith, and wherein an AC spacer is disposed on the contact area and is arranged such that the AC spacer serves as an AC connecting element to the topmost layer of the first printed circuit board.

[0012] In one embodiment, the topmost layer of the second printed circuit board is structured such that a second partial area of ​​the topmost layer serves as a signal / control connection, and wherein a spacer is disposed on the signal / control connection and is arranged such that the spacer serves as a connecting element to the signal / control connection on the topmost layer of the first printed circuit board.

[0013] In one embodiment, the uppermost layer of the first printed circuit board is guided over its entire surface on the power semiconductor.

[0014] In one embodiment, the heat sink is respectively arranged on the lowermost layer of each printed circuit board and is thermally coupled thereto.

[0015] In one embodiment, the circuit board is a DBC circuit board or an AMB circuit board or an IMS circuit board.

[0016] Furthermore, a method for mounting a power electronic device module is provided, wherein in a first step, the power semiconductors are applied to the associated circuit board, and in a subsequent third step, the connection of the load connections and the signal / control connections to the associated tracks is established with the aid of one or two lead frames, and in a fourth step, the circuit boards are connected to one another in that the two uppermost layers of the circuit boards with the power semiconductors arranged thereon are applied one on top of another and connected at specified areas.

[0017] In one embodiment, the power electronics module is surrounded by a potting compound in a fifth step and one or more lead frames are removed in a sixth step, so that only tracks and contact elements connected to signal / control connections still protrude from the potting compound.

[0018] In one embodiment, in a second step arranged between the first and third step or after the third step, the spacer element is applied to the power semiconductor and / or to the uppermost layer of the printed circuit board.

[0019] Furthermore, an electric drive of a vehicle is provided, which has a power electronics component which has at least the described power electronics module.

[0020] Further features and advantages of the invention are apparent from the following description of exemplary embodiments of the invention with the aid of the drawings, which illustrate details according to the invention, and from the claims. The individual features can be realized individually or in any combination in variants of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Preferred embodiments of the present invention are explained in more detail below with reference to the accompanying drawings.

[0022] Figure 1 A sectional view showing the basic structure of a power electronics module with double-sided cooling according to the prior art;

[0023] Figure 2 A cross-sectional view showing the principle structure of a power electronics module with double-sided cooling according to an embodiment of the present invention;

[0024] Figure 3 A sectional view showing the basic structure of a power electronics module with double-sided cooling according to an alternative embodiment of the present invention;

[0025] Figure 4 A diagram showing the basic structure of a power electronics module with double-sided cooling according to one embodiment of the present invention;

[0026] Figure 5 A view showing a schematic structure of an upper circuit board with a lead frame according to an embodiment of the present invention;

[0027] Figure 6 A view showing a schematic structure of an upper circuit board without a lead frame according to an embodiment of the present invention;

[0028] Figure 7 A view showing a schematic structure of a circuit board with a lead frame underneath according to an embodiment of the present invention;

[0029] Figure 8 A view showing a schematic structure of a circuit board without a lead frame underneath according to an embodiment of the present invention;

[0030] Fig. 9 A diagram showing the basic structure of a power electronics module with a lead frame and double-sided cooling according to an embodiment of the present invention;

[0031] Fig.10 A view showing the principle structure of an upper circuit board according to another embodiment of the present invention;

[0032] Fig.11 A view showing the principle structure of a circuit board without a lead frame and with (AC / DC / signal / control) tracks underneath according to another embodiment of the present invention;

[0033] Fig.12 A view showing a schematic structure of a circuit board having a lead frame underneath according to another embodiment of the present invention;

[0034] Fig.13 A view showing the basic structure of a power electronics module with a lead frame and double-sided cooling according to another embodiment of the present invention;

[0035] Fig.14 A diagram showing the basic structure of a power electronics module without a lead frame and with double-sided cooling according to another embodiment of the present invention;

[0036] Fig.15 A method sequence for producing a power electronics module with double-sided cooling according to a further embodiment of the present invention is shown.

[0037] In the following description of the figures, identical elements or functions are provided with the same reference symbols. DETAILED DESCRIPTION

[0038] According to the invention, for use in power electronics components such as inverters (DC / AC converters) in the automotive sector, double-sided cooling is provided for power electronics modules, wherein electrical commutation is improved, thermal connection is optimized and a simple design of the power electronics module 100 is provided.

[0039] The power electronics module 100 usually provides one phase of the inverter (with AC phase tapping). In order to obtain a three-phase inverter, three of the power electronics modules 100 are connected together. Different methods are known for this purpose, which are not described in detail here. Since usually identical power electronics modules 100 are connected together, the present description is limited to a single power electronics module 100.

[0040] With the help of Figure 2The double-sided cooled power electronic device module 100 described below has two circuit boards 1, 2, which have at least three layers, wherein the uppermost layers 10, 20 are formed from an electrically conductive material, the middle layers 11, 21 are formed from a non-conductive material, such as ceramic, and the lowermost layers 12, 22 are formed from an electrically conductive material. Such a circuit board is, for example, a DBC circuit board. DBC stands for direct bonded copper, wherein the abbreviation DCB (direct copper bonded) can also be used. However, it is also possible to use, for example, AMB (Active Metal Brazing) or IMS (Insulated metal substrate) circuit boards, as long as they have at least three of the above-mentioned layers.

[0041] According to the invention, the uppermost layer 10 of the first printed circuit board 1 is used as an AC contact (AC). The uppermost layer 20 of the second printed circuit board 2 is used as a DC phase contact (DC- and DC+). Furthermore, after final assembly, the two printed circuit boards 1 , 2 point toward each other with their two uppermost layers 10 , 20 , that is, the two uppermost layers 10 , 20 face each other.

[0042] Furthermore, the power electronics module 100 has at least one half-bridge, namely at least one power semiconductor 3 . 1 arranged in a high-side circuit and formed as a high-side switch (hereinafter referred to as high-side switch 3 . 1 ) and a power semiconductor 3 . 2 arranged in a low-side circuit and formed as a low-side switch (hereinafter referred to as low-side switch 3 . 2 ).

[0043] The low-side line, i.e. one (or more) low-side switches 3.2, is arranged on the uppermost layer 10 of the first circuit board 1, with its AC phase contact (the drain D in the case of MOSFET, the collector corresponding to the drain in the case of IGBT) in electrical contact with the uppermost layer 10. Therefore, its DC contact (the source in the case of MOSFET, the emitter corresponding to the source in the case of IGBT) points in the direction of the uppermost layer 20 of the second circuit board 2.

[0044] In a preferred embodiment, the spacer element 4 is arranged on the DC contact (here S) of the low side switch 3 . 2 and is in electrical and thermal contact both with the DC contact (here S) and with the uppermost layer 20 of the second printed circuit board 2 .

[0045] In an alternative embodiment ( Figure 3), in the low-side circuit, the DC contact (source S in the case of a MOSFET, emitter corresponding to the source in the case of an IGBT) is directly (overall) in contact with the uppermost layer 20 of the second printed circuit board 2 and the spacer element 4 is arranged over all areas on the AC phase contact (drain D in the case of a MOSFET, collector corresponding to the drain in the case of an IGBT) and in contact with the uppermost layer 10 of the first printed circuit board 1. This embodiment is less advantageous because it is more difficult to provide contacting of the signal / control connection 7 described below in terms of production technology.

[0046] The high-side line, i.e., one (or more) high-side switches 3.1, is arranged on the uppermost layer 20 of the second circuit board 2, with its DC contact (the drain D in the case of MOSFET, the collector corresponding to the drain in the case of IGBT) in electrical contact with the uppermost layer 20. Therefore, its AC phase contact (the source S in the case of MOSFET, the emitter corresponding to the source in the case of IGBT) points in the direction of the uppermost layer 10 of the first circuit board 1. In one embodiment, the spacer element 4 is arranged on the AC phase contact (here S) of the high-side switch 3.1 and is in electrical and thermal contact with both the AC phase contact (here S) and the uppermost layer 10 of the first circuit board 1.

[0047] In the embodiment shown, the low side line is arranged on the first circuit board 1 before final mounting and the high side line is arranged on the second circuit board 2 before final mounting.

[0048] The spacing element 4 of the two lines (high side and low side) is formed from an electrically and thermally conductive material, such as copper. The high side switch 3.1 and the low side switch 3.2 usually have the same outer dimensions and the spacing element 4 advantageously has the same height, so that the two circuit boards 1 and 2 can be connected to each other with the smallest possible tolerances. Tolerance compensation is also performed when the two circuit boards 1, 2 are brought together, for example by introducing solder.

[0049] On the side of the AC phase contact of each power semiconductor 3.1, 3.2, a signal / control connection 7 is arranged, so that the entire surface of the power semiconductor 3.1, 3.2 is not occupied by the AC phase contact (load connection for AC). The spacing element 4 is therefore formed as follows, that is, the spacing element does not occupy the entire surface of the respective power semiconductor 3.1, 3.2, but leaves a part of the surface free, on which no load connection is arranged, but signal / control connection 7 is arranged. These signal / control connection 7 can be gate connection or Kelvin source connection. Therefore, the space for contacting the signal / control connection 7 by means of contact elements such as wire bonding is at least at the height of the spacing element 4. A cooling element (not shown) can also be arranged as an intermediate element on this free space, which cooling element allows additional heat dissipation (heat diffusion).

[0050] Depending on the embodiment and the assembly method, the signal / control connection 7 can be provided as part of the printed circuit board 1 , 2 or as an external connection, as will be explained below with reference to the assembly or production method.

[0051] Circuit boards 1 , 2 serve not only as electrical contacts but also as heat conductors in order to dissipate heat to heat sinks 5 , 6 arranged in each case on the lowermost layer 12 , 22 and thus cool power semiconductors 3 . 1 and 3 . 2 .

[0052] According to the present invention, the low side switch 3.2 is arranged in a 180° rotation (horizontal mirror) relative to the high side switch 3.1, so that the AC connections of the two power semiconductors 3.1 and 3.2 point in the same direction, that is, in the direction of the uppermost layer 10 of the first circuit board 1, and are in electrical and thermal contact therewith (depending on the embodiment, also through the spacing element 4). In addition, the DC connections of the two power semiconductors 3.1 and 3.2 point in the same direction, that is, in the direction of the uppermost layer 20 of the second circuit board 2, and are in electrical and thermal contact therewith (depending on the embodiment, also through the spacing element 4). Due to this arrangement, an optimized commutation unit is achieved by the three-dimensional arrangement of DC+, phase AC and DC- compared to the prior art. In addition, this design achieves optimized double-sided cooling of all power semiconductors 3.1, 3.2, because the connected spacing element 4 also enables heat flow to the second circuit board 2 in addition to power flow.

[0053] The direct (overall) connection of the drain D of the individual power semiconductors 3 . 1 and 3 . 2 (in the case of MOSFETs) to the uppermost layer 10 , 20 of the respective circuit board 1 , 2 simplifies the production of the power electronics module 100 compared to the prior art, since, for example, wire bonds or connecting elements can also be omitted.

[0054] As already explained, the signal / control connections 7, but also the load connections (DC and AC), can also be arranged slightly differently depending on the installation or production method, as explained below. The sequence of the installation or production method according to one embodiment is as follows. Fig.15 It is schematically shown in FIG.

[0055] In a first embodiment of the assembly or production method, a power electronics module 100 is obtained, such as Figure 4 As shown. To this end, in a first step S1, the power semiconductors 3.1 and 3.2 are mounted on the corresponding circuit boards 1, 2 (the low side is mounted on the first circuit board 1 and the high side is mounted on the second circuit board 2). The power semiconductors 3.1 and 3.2 are advantageously sintered thereto (instead of being soldered thereto). As a result, the DC contact of the high-side switch 3.1 (the drain D in the case of a MOSFET) is mounted on the uppermost layer 20 of the circuit board 2 and the AC phase contact of the low-side switch 3.2 (the drain D in the case of a MOSFET) is mounted on the uppermost layer 10 of the first circuit board 1 and is connected there in a thermally and electrically conductive manner. The uppermost layer 10 of the circuit board 1 continues to exist in its entirety here, i.e. is not structured, as in Figure 5 and Figure 6 The uppermost layer 20 of the circuit board 2 is structured so as to electrically separate DC+ and DC- from each other, as shown in FIG. Figure 7 and Figure 8 As can be clearly seen in .

[0056] In the second step S2, the spacer element 4 is mounted either on the power semiconductors 3.1 and 3.2 or on the printed circuit boards 1, 2. Alternatively, the spacer element 4 can also be mounted after or in the third step S3, advantageously after the signal / control connection 7 has been contacted with the associated track (signal / control track 8) by means of the connecting element. The sequence depends on the connecting element used.

[0057] In a third step S3, the connection of the load connections DC, AC and the signal / control connections 7 to the associated tracks (DC track DC-S, AC track AC-S, signal / control track 8) is established. This is achieved by using so-called lead frames LF1, LF2. In the described assembly or production method of the first embodiment, two lead frames LF1, LF2 are required, so that two partial circuit boards 1, 2 with corresponding connections are produced. As in Figure 5 As shown in FIG. 1 , the first lead frame LF1 carries the AC rail AC-S and the signal / control rail 8 of the low-side switch 3.2, i.e., belongs to the first circuit board 1. Figure 61 shows the first circuit board 1 with the AC rail AC-S and the signal / control rail 8 after removing the unnecessary partial area of ​​the lead frame LF1 in order to show the structure. Figure 7 As shown in FIG, the second lead frame LF2 carries the DC rails DC-S of DC+ and DC- and the signal / control rails 8 of the high-side switch 3.1, i.e., belongs to the second circuit board 2. Figure 8 2 shows the second circuit board 2 with the DC rail DC-S and the signal / control rail 8 after removing unneeded partial areas of the lead frame LF2 in order to show the structure.

[0058] In a fourth step S4, the two lead frames LF1, LF2 are combined with the (equipped) circuit boards 1, 2 connected thereto by mounting the two upper layers 10, 20 of the circuit boards 1, 2 together with the power semiconductors 3.1, 3.2 arranged thereon and the spacing elements 4 one above the other and connecting them to one another at defined areas, for example by sintering. These areas are either the (free) side of the spacing elements 4 opposite the power semiconductors 3.1, 3.2 (in a preferred embodiment, such as Figure 2 ), either the (free) side of the spacing element 4 opposite the power semiconductor 3.1 and the DC contact of the power semiconductor 3.2 (in a preferred embodiment, as shown Figure 3 ). Fig. 9 , an oblique view of the combined circuit boards 1 and 2 with the lead frames LF1 and LF2 is shown. Figure 4 , the power electronics module 100 (with outwardly directed load rails DC-S, AC-S and signal / control rail 8 ) obtained after removal of certain unneeded parts of the lead frames LF1 , LF2 is shown in an oblique view.

[0059] In a fifth step S5, the power electronics module 100 is surrounded by a potting compound (not shown) in order to provide protection from environmental influences. This potting compound also serves to keep the signal / control tracks 8 in their position, because otherwise these signal / control tracks would only be suspended at the connection (e.g. wire bond) after the lead frames LF1, LF2 are removed. The lead frames LF1, LF2 are removed in the last step S6 only after potting. The potting compound surrounds the power electronics module 100 so that only the load tracks DC-S, AC-S and certain parts of the signal / control tracks 8 still protrude out of the potting compound after the lead frames LF1, LF2 are removed.

[0060] As in Figure 4 As can be clearly seen in FIG. 1 , a spacing remains between the DC rail DC-S and the printed circuit board 1 and between the AC rail AC-S and the printed circuit board 2 after the connection, so that no contact is produced here.

[0061] In a second embodiment of the assembly or production method, a power electronics module 100 is obtained, such as in Fig.14 For this purpose, the power semiconductors 3.1 and 3.2 are mounted, preferably sintered, on the respective printed circuit boards 1, 2, as in the first embodiment.

[0062] As in Fig.10 As can be clearly seen in the figure, the uppermost layer 10 of the first printed circuit board 1 is here located entirely in the region of the power semiconductors 3.1 and 3.2, but is structured in the edge region in order to provide islands 101 for (electrical) contacting of the signal / control connections 7 of the power semiconductors 3.2 arranged on the uppermost layer 10 of the first printed circuit board 1 with the signal / control tracks 8 provided in a later step. The spacer elements 4 are also mounted on the power semiconductors 3.1 and 3.2 or on the printed circuit boards 1, 2, as in the first embodiment.

[0063] As in Fig.11 As can be clearly seen in FIG. 2 , the uppermost layer 20 of the lower printed circuit board 2 is structured so that the load connections (DC and AC) and all signal / control connections 7 can be provided.

[0064] In this embodiment, the spacer element 4 is additionally mounted on the uppermost layer 20 of the lower circuit board 2, and the AC phase tap AC (island area is part of the uppermost layer 20, as shown in Fig.11 ) and the signal / control connection 7 are located thereon.

[0065] Alternatively, all the spacer elements 4 of the two printed circuit boards 1 , 2 can also be mounted only after the signal / control connections 7 have been contacted with the associated tracks (signal / control tracks 8 ). This sequence depends on the connecting elements used.

[0066] Based on the spacing element 4 on the lower circuit board 2, in this mounting or manufacturing method, only one lead frame LF1 is required, because all load rails (DC-S and AC-S) and all signal / control rails 8 are connected on the lower circuit board 2, as in Fig.12 As can be clearly seen in . Fig.12 The following figure shows the circuit board 2 and the lead frame LF1 arranged thereon. Fig.11 Shown is the circuit board 2 with the lead frame LF1 removed, ie with the load tracks (DC-S and AC-S), and all signal / control tracks 8, but without the circuit board 1 above. Fig.13The printed circuit boards 1 , 2 are shown joined together, which, as in all embodiments, point toward one another with their uppermost layers 10 , 20 and the power semiconductors 3 . 1 , 3 . 2 arranged thereon, with the leadframe LF1 still being present. Fig.14 The interconnected circuit boards 1, 2 are shown without the lead frame LF1. As in the previous embodiments, the potting compound surrounding the power electronics module 100 is not shown here, so that only the load tracks DC-S, AC-S and certain parts of the signal / control tracks 8 protrude out of the potting compound.

[0067] In order to provide contact between the AC rail AC-S and the signal / control rail 8 and the upper circuit board 1, in this embodiment, the spacer 70 is arranged on the lower circuit board 2 in the area of ​​the island 201 (part of the uppermost layer 20), on which the signal / control rail 8 is placed. In addition, the AC spacer 9 is arranged in the area of ​​the AC contact portion of the AC rail AC-S (the uppermost layer 20). These spacers 70, 9 are formed from an electrically and thermally conductive material such as copper and are used to establish contact between the components of the first and second circuit boards 1, 2 (in particular electrically). They therefore serve as connecting elements. The spacing element 4 (of the power semiconductor 3.1, 3.2) is advantageously made of the same material as the spacers 70, 9.

[0068] The spacers 70 , 9 can be mounted on the circuit boards 1 , 2 in a separate process step or together with other components, such as the spacing elements 4 .

[0069] By means of additional spacers 70, 9 on the lower circuit board 2 (on the uppermost layer 20 of the lower circuit board), only a single lead frame LF1 can be used. By means of the spacers 70, 9, the AC phase AC and the signal / control contact 7 of the circuit board 1 are electrically (and thermally) contacted in such a way that the two circuit boards 1, 2 are connected to one another, as in Fig.13 and 14 As shown in Fig.14 As can be clearly seen in FIG. 1 , a distance remains between the DC rail DC-S and the printed circuit board 1 after the connection, so that no contact is produced here.

[0070] In all embodiments, it is provided that the connection (electrical / thermal contact) is established by means of sintering. This can avoid the need to use solders with different melting temperatures. However, it can be provided that the solder used for the final connection is used for tolerance compensation. Alternatively, a material-locking connection can be made by a technique such as "Velcro welding".

[0071] In all embodiments, the heat sinks 5 , 6 are arranged on the lowermost layer 12 , 22 of the printed circuit boards 1 , 2 in order to dissipate the waste heat outside the power electronics module 100 .

[0072] The power electronics module 100 is used within the scope of the present invention to operate a motor vehicle driven by an electric motor (with a battery). The motor vehicle is in particular a commercial vehicle such as a truck or a bus or a private car. The power electronics module includes a DC / AC inverter. In addition, the power electronics module may also include an AC-DC rectifier, a DC / DC converter, a transformer and / or other electrical converters or a part of such a converter or may be a part of them. The power electronics module 100 is particularly used to energize an electric motor, such as an electric motor and / or a generator. The DC / AC inverter is preferably used to generate a multi-phase alternating current from a direct voltage generated by an energy source, such as a DC voltage of a battery (battery).

[0073] Reference numerals list

[0074] 100 Power Electronics Modules

[0075] 1First Circuit Board

[0076] 10The top layer

[0077] 101 Islands / Contact Area

[0078] 11 Middle Layer

[0079] 12The bottom layer

[0080] 2 Second circuit board

[0081] 20The top layer

[0082] 201 Islands / Contact Area

[0083] 21 Middle Layer

[0084] 22The bottom layer

[0085] 3.1 High-side power semiconductors

[0086] 3.2 Low-side power semiconductors

[0087] S Source (Emitter)

[0088] D drain (collector)

[0089] 4 Spacer elements

[0090] 5.6 cooling body

[0091] 7Signal / control connection (gate / Kelvin source connection)

[0092] 70 Spacer

[0093] 8 signal / control lines

[0094] AC spacer for 9AC rails

[0095] ACAC Connection Department

[0096] AC-SAC trajectory

[0097] DCDC connection (DC- or DC+)

[0098] DC-SDC track

[0099] LF1 lead frame 1

[0100] LF2 lead frame 2

Claims

1. A power electronic device module (100), the power electronic device module comprising: - a first circuit board (1), the first circuit board having an uppermost layer (10) made of an electrically conductive material, a middle layer (11) made of an electrically non-conductive material and a lowermost layer (12) made of an electrically conductive material; and a second circuit board (2), the second circuit board having an uppermost layer (20) made of an electrically conductive material, a middle layer (21) made of an electrically non-conductive material and a lowermost layer (22) made of an electrically conductive material, and - a high-side circuit with at least one power semiconductor (3.1) designed as a high-side switch, and a low-side circuit with at least one power semiconductor (3.2) designed as a low-side switch, wherein: - the first circuit board (1) and the second circuit board (2) are arranged opposite each other so that the uppermost layers (10, 20) face each other, And among them, The uppermost layer (10) of the first circuit board (1) is used as an AC phase connection (AC), and the uppermost layer (20) of the second circuit board (2) is structured so that it is used as a DC negative connection and a DC positive connection (DC), and - A power semiconductor (3.1) formed as a high-side switch and a power semiconductor (3.2) formed as a low-side switch are arranged so that their AC connection parts point to and contact the uppermost layer (10) of the first circuit board (1), and the DC connection parts of the power semiconductors (3.1, 3.2) point to and contact the uppermost layer (20) of the second circuit board (2).

2. The power electronic device module (100) according to claim 1, wherein: Each power semiconductor (3.1, 3.2) is provided with a spacing element (4), and wherein: - a spacer element (4) of a power semiconductor (3.1) formed as a high-side switch is arranged between the uppermost layer (10) of the first circuit board (1) and the power semiconductor (3.1) and is in electrical and thermal contact with the first circuit board (1) and the power semiconductor (3.1), and wherein: - a spacer element (4) of a power semiconductor (3.2) formed as a low-side switch is arranged between the uppermost layer (20) of the second circuit board (2) and the power semiconductor (3.2) and is in electrical and thermal contact with the second circuit board (2) and the power semiconductor (3.2), or a spacer element (4) of a power semiconductor (3.2) formed as a low-side switch is arranged between the uppermost layer (10) of the first circuit board (1) and the power semiconductor (3.2) and is in electrical and thermal contact with the first circuit board (1) and the power semiconductor (3.2).

3. The power electronics module (100) according to any of the preceding claims, further comprising at least one signal / control track (8) for each power semiconductor (3.1, 3.2), wherein: At least one signal / control connection (7) is provided on the side of each power semiconductor (3.1, 3.2) to be contacted with one of the DC connections, said signal / control connection being contacted with an associated signal / control track (8) by means of a connecting element.

4. The power electronics module (100) according to any one of the preceding claims, wherein: The uppermost layer (20) of the second printed circuit board (2) is structured so that a first partial area thereof serves as a contact area for an AC track (AC-S) to be contacted therewith, and an AC spacer (9) is arranged on the contact area and is arranged so that the AC spacer serves as an AC connecting element to the uppermost layer (10) of the first printed circuit board (1).

5. The power electronic device module (100) according to claim 4, wherein: The uppermost layer (20) of the second printed circuit board (2) is structured so that a second partial area thereof is used as a signal / control connection portion (7), and a spacer (70) is provided on the signal / control connection portion (7) and arranged so that the spacer serves as a connecting element to the signal / control connection portion (7) on the uppermost layer (10) of the first printed circuit board (1).

6. The power electronics module (100) according to any one of the preceding claims, wherein: The uppermost layer (10) of the first printed circuit board (1) is guided over the entire surface of the power semiconductor (3.1, 3.2).

7. The power electronics module (100) according to any one of the preceding claims, wherein: The heat sinks (5, 6) are respectively arranged on the lowermost layer (12, 22) of each printed circuit board (1, 2) and are thermally coupled thereto.

8. The power electronics module (100) according to any one of the preceding claims, wherein: The circuit boards (1, 2) are DBC circuit boards, AMB circuit boards, or IMS circuit boards.

9. A method for mounting a power electronic device module according to any one of claims 1 to 8, wherein: - In a first step (S1), power semiconductors (3.1, 3.2) are mounted on associated printed circuit boards (1, 2), and - in a subsequent third step (S3), the load connections (DC, AC) and the signal / control connections (7) are connected to the associated tracks (AC-S, DC-S, 8) by means of one or two lead frames (LF1, LF2), and In a fourth step (S4), the printed circuit boards (1, 2) are joined together by applying the two uppermost layers (10, 20) of the printed circuit boards (1, 2) with the power semiconductors (3.1, 3.2) arranged thereon one above the other and connecting them at specified areas.

10. The installation method according to claim 9, wherein: In a fifth step (S5), the power electronics module (100) is surrounded by a potting compound, and in a sixth step (S6), the lead frame (LF1, LF2) is removed so that only tracks (AC-S, DC-S, 8) and contact elements connected to the signal / control connection (7) protrude from the potting compound.

11. The installation method according to claim 9 or 10, wherein: In a second step (S2) arranged between the first and third steps (S1, S3) or after the third step (S3), a spacer element (4) is applied to the power semiconductor (3.1, 3.2) and / or to the uppermost layer (10, 20) of the circuit board (1, 2). 12 . An electric drive for a vehicle, comprising a power electronics component having at least one power electronics module ( 100 ) according to claim 1 .

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