Power semiconductor module and assembly for traction converter

Abstract

The present invention relates to a power semiconductor module (18) for a traction converter (12), comprising at least two identical semiconductor packages (20) arranged as switches in a half-bridge circuit, each semiconductor package comprising: a power semiconductor (22) with a first side (30), a opposite second side (32) and a control terminal (34) on the first side; a first contacting unit (24) for contacting the first side, which is thermally and electrically contacted over a large area with the first side; a second contacting unit (26) for contacting the second side, which is thermally and electrically contacted over a large area with the second side; and a connector (28) for connecting the control terminal of the power semiconductor to a control unit (21).The present invention further relates to an assembly (56a, 56b) for a power semiconductor module (18) and a traction converter (12).

Description

[0001] The present invention relates to a power semiconductor module for a traction converter. Furthermore, the present invention relates to an assembly for a power semiconductor module and a traction converter.

[0002] The power electronics of electric and hybrid vehicles transfer traction energy from the battery to the electric motor, converting direct current (DC) into alternating current (AC). This is accomplished using an AC converter, also known as an inverter or traction converter. Typically, this involves the use of multiple transistors or other power semiconductors, which are combined into a power semiconductor module and switch at short, regular intervals. MOSFETs (metal-oxide-semiconductor field-effect transistors), IGBTs (insulated-gate bipolar transistors), and JFETs (junction field-effect transistors) are commonly used as switches. When switched on, the battery current is passed to the motor (conducting phase). These high-frequency switching operations create an AC voltage waveform that can then be converted into traction energy in the electric motor.To increase the current-carrying capacity, several power semiconductors are usually connected in parallel.

[0003] The manufacturing process for such power semiconductor modules typically involves several technically demanding steps. The individual power semiconductors (also called chips or semiconductor chips) are deposited onto a ceramic substrate, which is also suitable for dissipating the generated heat. The ceramic substrate is then applied to a base plate with a cooling structure, using processes such as soldering, sintering, or thermal grease application. The drain, source, and gate connections of the individual power semiconductors are usually made using wire bonding. Thin wires are connected to the corresponding terminals of the power semiconductor to electrically connect these terminals to the appropriate leads. After bonding, several power semiconductors or a power semiconductor module are usually encapsulated in a potting compound to form a package.To provide a semiconductor package that can then be used as a component in a traction converter.

[0004] In this context, DE 10 2022 202 254 A1 discloses a modular half-bridge module formed from at least two power semiconductor modules. Each power semiconductor module comprises a first outer substrate, a semiconductor switch chip, an intermediate substrate, a diode chip, and a second outer substrate, stacked together in that order. The semiconductor switch is bonded to the first outer substrate with a positive terminal and to the intermediate substrate with a negative terminal. The diode chip is bonded to the second outer substrate with an anode terminal and to the intermediate substrate with a cathode terminal. The diode chip is electrically connected to the semiconductor switch chip via the substrates in an antiparallel configuration. The at least two power semiconductor modules are electrically connected to each other to form a half-bridge.

[0005] Due to the comparatively difficult handling of power semiconductors (chip handling) and the relatively complex contacting process, this manufacturing process is often complex and offers little variation. For a power semiconductor module with higher / lower power, a different form factor, or a different number of individual power semiconductors within the module, a complete overhaul of the manufacturing process is often necessary. This leads to high costs, low efficiency, and poor scalability.

[0006] Based on this, the present invention aims to provide an approach for supplying an efficiently manufacturable and flexibly deployable power semiconductor module for traction converters. In particular, it aims to enable the most efficient manufacturing possible at low cost, as well as flexibility with regard to implementing different form factors and performance requirements.

[0007] To solve this problem, the present invention relates in a first aspect to a power semiconductor module for a traction converter, with at least two identical semiconductor packages arranged as switches in a half-bridge circuit, wherein the semiconductor packages each comprise: - a power semiconductor with a first side, an opposing second side and a control terminal on the first side; - a first contacting unit for contacting the first side, which is thermally and electrically contacted over a large part of the first side; - a second contacting unit for contacting the second side, which is thermally and electrically contacted over a large area of ​​the second side; and - a connector for connecting the control terminal of the power semiconductor to a control unit.

[0008] In another aspect, the present invention relates to an assembly for a power semiconductor module according to one of the preceding claims, comprising: - at least two identical and aligned semiconductor packages in a parallel circuit, which together form a switch in the half-bridge circuit; - a common external heat sink that is thermally contacted with the first contacting units of the parallel-connected semiconductor packages; - a common AC contact point that is electrically contacted with the second contacting units of the parallel-connected semiconductor packages; and - a common DC contact point that is electrically contacted with the first contacting units of the parallel-connected semiconductor packages.

[0009] Furthermore, one aspect of the invention relates to a traction converter for a vehicle with a power semiconductor module as previously described or with two assemblies as previously described and a control unit for controlling the power semiconductors via their control connections.

[0010] Furthermore, one aspect of the invention relates to a traction converter for a vehicle with three power semiconductor modules as previously described, which are assigned to the three phases of an electric motor.

[0011] Preferred embodiments of the invention are described in the dependent claims. It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the present invention. In particular, the assembly and the traction converter can be configured according to the embodiments described for the power semiconductor module in the dependent claims.

[0012] According to the invention, at least two semiconductor packages are used as switches in a half-bridge circuit within a power semiconductor module (high-side and low-side switches). The two semiconductor packages are identical in design. A planar electrical and thermal contact is provided on both sides of the power semiconductor. In one of the two semiconductor packages, the first side of the power semiconductor corresponds to the source terminal. In the other semiconductor package, the first side of the power semiconductor corresponds to the drain terminal. The contact units serve both to supply or discharge the (high) current and to dissipate the heat generated during switching.

[0013] The two contact units in the two semiconductor packages each have a large area of ​​contact with a significant portion of the first or second side of the power semiconductor, respectively. This results in good electrical and thermal contact. High currents can be conducted and heat can be efficiently dissipated. Losses are minimized. In contrast to previous approaches, the current flow is perpendicular to a plane of the power semiconductor.

[0014] The control terminal of the power semiconductor (gate terminal) is connected via the connector. According to the invention, the control terminal is located on the first side of the power semiconductor. The connection is made to a corresponding control unit (not part of the semiconductor package). The control unit can, for example, be configured for controlling the power semiconductor or for switching. For example, the control unit can be centrally located in the traction converter.

[0015] The power semiconductor module is specifically designed for use in a vehicle traction converter. In this traction converter, the direct current from a battery is converted into an alternating current for an electric motor. In particular, the use of three power semiconductor modules for three phases of an electric motor is possible. Since comparatively high currents are switched, it is understood that a plurality of semiconductor packages according to the invention are typically connected in parallel within a single power semiconductor module, or several power semiconductor modules connected in parallel are used for switching.

[0016] The semiconductor packages in the power semiconductor module according to the invention correspond to Chip Scaled / Sized Packages (CSP). By combining at least two identical semiconductor packages into a single power semiconductor module, efficient manufacturing of a traction converter is enabled. Suitable power semiconductor modules can be provided or combined to meet different power requirements. This reduces manufacturing and adaptation costs and results in improved manufacturing flexibility.

[0017] In one embodiment, the power semiconductors of the two semiconductor packages are aligned parallel to each other and arranged in different planes, particularly in a flush configuration. The power semiconductors are typically planar chips. These are arranged parallel to each other in different planes. A flush configuration is defined as an arrangement in which both power semiconductors share a common central axis perpendicular to the chip surface. Furthermore, their rotational orientation with respect to this axis can be identical. The semiconductor packages, or rather the power semiconductors, are thus arranged one above the other. This results in a three-dimensional arrangement that allows for variability in the form factors of the power semiconductor module.

[0018] In one embodiment, the power semiconductor module comprises two external heat sinks arranged on both sides of the two semiconductor packages relative to the planes of the power semiconductors, each thermally contacted with the contacting unit of one semiconductor package facing away from the other. The external heat sinks are preferably electrically insulated from the semiconductor packages by means of an insulating layer, in particular an insulating film. An arrangement on both sides is understood to mean, in particular, an arrangement along an axis perpendicular to the planes of the power semiconductors, both above and below the semiconductor packages. In this respect, the externally arranged heat sinks also enable a three-dimensional design of the power semiconductor module, in which, if necessary,Several semiconductor packages can be arranged in one plane, and additional semiconductor packages can be arranged in another parallel plane. The external heat sinks are then positioned on the outside of both planes. Heat dissipation is facilitated via the contact unit. Insulation is required, particularly for electrically conductive external heat sinks, and this can be provided by an insulating layer, especially an insulating film.

[0019] In one embodiment, the power semiconductor module comprises an intermediate heat sink arranged between the two semiconductor packages and thermally contacted by the contacting unit of one semiconductor package facing the other. The intermediate heat sink is preferably electrically insulated from the semiconductor packages by means of an insulating layer, in particular an insulating film. Unlike an external heat sink, the intermediate heat sink is located between the two semiconductor packages. In particular, the intermediate heat sink can also extend substantially along a plane parallel to the two power semiconductors. In a three-dimensional arrangement, the intermediate heat sink facilitates heat dissipation from the area between the semiconductor packages. This further improves heat dissipation and thus performance.

[0020] In one embodiment, the two semiconductor packages are aligned in the same direction, such that the first side of the power semiconductor of one semiconductor package faces the same direction as the first side of the power semiconductor of the other semiconductor package. In other words, both semiconductor packages are identically oriented. The two first contact units point in the same direction. The power semiconductors and their other components are oriented identically. This arrangement facilitates simple manufacturing.

[0021] In one embodiment, a first contact unit of one semiconductor package and a second contact unit of the other semiconductor package each form an AC output and are electrically contacted via a common AC contact. The AC contact is preferably arranged between the semiconductor packages and / or electrically connected to the first contact unit of one semiconductor package and the second contact unit of the other semiconductor package by means of sintered connections. The AC output can, in particular, correspond to the output of the half-bridge circuit through which the alternating current generated in the traction converter is routed to the electric motor. The AC contact corresponds to the component through which the two contact units are connected. For example, a busbar or another suitable electrical connection can be used.Contact via sintered connections can be implemented efficiently and enables a robust and durable connection. Mechanical stability can be guaranteed at comparatively low manufacturing costs.

[0022] In one embodiment, the two semiconductor packages are arranged rotated 180° relative to each other, so that the first side of the power semiconductor of one semiconductor package is oriented in the same direction as the second side of the power semiconductor of the other semiconductor package. One semiconductor package is, in effect, upside down with respect to the other. A 180° rotation, therefore, means a reversed orientation. This also enables a three-dimensional structure of the power semiconductor module. This results in a variability in terms of achievable form factors.

[0023] In one embodiment, the power semiconductor module comprises at least six identical semiconductor packages, with two semiconductor packages arranged as switches in three half-bridge circuits for three phases of an electric motor. In particular, it is possible to combine a large number of semiconductor packages to achieve higher power outputs. For example, two semiconductor packages per phase of an electric motor can be provided for the two semiconductors of a half-bridge circuit as a minimum configuration. However, more commonly, several semiconductor packages are connected in parallel for each half-bridge circuit or for each side of the half-bridge circuit to achieve higher power outputs. This results in efficient scalability and, consequently, manufacturing efficiency, since different power outputs can be achieved using the same basic components.

[0024] In one embodiment, the power semiconductor module comprises at least four identical semiconductor packages, with at least two identically oriented semiconductor packages arranged in parallel and together forming a switch in the half-bridge circuit. In this embodiment, (at least) two parallel semiconductor packages are provided per switch. This results in a doubling of the possible power output compared to using a single semiconductor package per switch in the half-bridge circuit. Scalability is achieved.

[0025] In one embodiment, the second side of the power semiconductor of one semiconductor package and the first side of the power semiconductor of the other semiconductor package each form a DC input and are oriented away from each other. The DC inputs are each connected to two poles of a DC voltage source via a DC contact. An orientation away from each other means that the respective contact elements point in opposite directions. In other words, the semiconductor packages are arranged rotated 180° relative to each other. The power semiconductors point in different directions. The DC input, to which the DC voltage source is connected, is located on the outer side of each semiconductor package, i.e., on the side facing away from the other semiconductor package. A DC contact, such as a busbar, is provided for this connection.In this respect, two different contact configurations are provided for the two poles of a DC voltage source. For example, two busbars can be provided.

[0026] In one embodiment, the power semiconductor module comprises two assemblies as described above, wherein the two assemblies are connected to each other on their sides facing the external heat sinks. Preferably, the connection is made using an electrically conductive and tolerance-compensating adhesive. The assembly according to the invention enables efficient manufacturing, since an arrangement with several semiconductor packages and a heat sink can be assembled and subsequently combined in varying numbers. By making contact on the side facing away from the external heat sinks, a first assembly can be used as a high-side switch and a second assembly as a low-side switch. A tolerance-compensating adhesive allows for a stable and durable connection, compensating for any manufacturing tolerances that may exist.

[0027] In one embodiment, the structurally identical semiconductor packages each comprise a maximum of two power semiconductors. Additionally or alternatively, the semiconductor packages are each encapsulated with a potting compound. By using a maximum of two, and preferably exactly one, power semiconductors in a single semiconductor package, a minimal package size is achieved. This maximizes flexibility in application. Furthermore, it offers additional advantages in the manufacturing process, such as eliminating the need for sorting the unprocessed power semiconductors, a comparatively complex process. The use of a potting compound results in a robust semiconductor package. Both hard and soft potting compounds can be used for this purpose.It is understood that, preferably, the corresponding contact points of the contacting units and the connector are led to the outside in order to be connected to corresponding current- or signal-carrying conductors.

[0028] In one embodiment of the structurally identical semiconductor packages, the first contact unit is designed as a metallization layer, preferably a copper metallization layer, or as a rigid component, preferably a copper block. Additionally or alternatively, the second contact unit is designed as a rigid component, preferably a copper carrier. A rigid component made of an electrically and thermally conductive material can be used for the first contact unit. Using a rigid component ensures good contact and also facilitates efficient manufacturing. The use of copper as the material provides good electrical and thermal conductivity. The use of a metallization layer may offer advantages in the manufacturing process and enable efficient production.The second contacting unit can be designed, in particular, as a support component (lead frame). The use of a rigid component also results in efficient manufacturability and mechanical stability.

[0029] In the configuration of the structurally identical semiconductor packages, the first contact unit is in contact with an area of ​​at least 60%, preferably at least 70%, and particularly preferably at least 80% of the first side of the power semiconductor. Additionally or alternatively, the second contact unit is in contact with an area of ​​the entire second side of the power semiconductor. Contact with a large portion of an area is understood to mean, in particular, contact extending over more than half of the area. Preferably, however, the contact is even more extensive and extends over a higher proportion of the area of ​​the first or second side of the power semiconductor. In particular, it is possible for the second contact unit to be in contact with the entire second side of the power semiconductor.For the first side, a slightly less reliable contact, both thermally and electrically, is accepted in order to also allow for the connection of the control terminal. This results in efficient manufacturability with good electrical and thermal properties.

[0030] In one embodiment of the structurally identical semiconductor packages, the connector comprises a flexible printed circuit board (PCB) with a conductor track. It is understood that additional conductor tracks can also be arranged on the flexible PCB, for example, to bring a Kelvin source terminal of the power semiconductor to the outside and allow for its control. Using a flexible PCB as the connector enables efficient manufacturing. Furthermore, it provides mechanical robustness. It also opens up further possibilities for the integration of additional components, such as a sensor.

[0031] In a preferred embodiment of the structurally identical semiconductor packages, a sintered connection is arranged between the first contact unit and the first side of the power semiconductor and / or between the second contact unit and the second side of the power semiconductor. Sintering can be selected as the connection technology. This results in a mechanically stable connection that is also electrically and thermally advantageous. Furthermore, efficient manufacturability can be achieved, as a sintered connection also allows for high temperatures.

[0032] In one embodiment of the structurally identical semiconductor packages, the cross-sectional area of ​​the first contact unit parallel to a plane of the power semiconductor is smaller in the region where the first contact unit makes contact with the first side of the power semiconductor than in a region spaced away from this point. Preferably, the change in cross-sectional area is discrete. Because the cross-section increases with increasing distance from the surface or the first side of the power semiconductor, heat dissipation can be improved. This results in a further improvement in the efficiency of operating the semiconductor package in a power semiconductor module of a traction converter. The change in cross-sectional area is preferably discrete. In particular, a step can be provided in which the cross-section increases abruptly.A discrete change in cross-sectional area can be manufactured efficiently. Furthermore, a kind of recess can be provided for the connector to attach the control terminal to the first side of the power semiconductor.

[0033] In one embodiment of the structurally identical semiconductor packages, the power semiconductor includes an additional control terminal on its first side. The connector is preferably designed to connect this additional control terminal to the control unit. In particular, a Kelvin source terminal can be provided as this additional control terminal. This terminal can also be connected to the control unit (which is not part of the semiconductor package) to provide and process a control signal. This results in further improved manufacturing efficiency for the semiconductor package. Semiconductor packages with additional functions can thus be provided.

[0034] In one embodiment, the semiconductor package does not include a planar insulating unit for electrically insulating a large portion of the first side of the power semiconductor and / or a large portion of the second side of the power semiconductor. In particular, the semiconductor package does not contain a ceramic layer. Such a layer enables electrical insulation while maintaining thermal conductivity. Even if a planar insulating unit, and especially a ceramic layer, is thermally conductive, it can often impede thermal flow. Therefore, omitting a planar insulating unit further improves the operability of the semiconductor package.

[0035] In this context, a power semiconductor module is understood to be, in particular, an assembly for use in an inverter or traction converter in a vehicle. A power semiconductor or semiconductor switch corresponds, in particular, to a transistor or a chip. A power semiconductor is, in particular, planar. Typically, several transistors are combined to form a topological switch. A power semiconductor module thus comprises several semiconductor switches or several power semiconductors. A power semiconductor module can include a power semiconductor assigned to a high-side and / or low-side. However, a power semiconductor module can also include power semiconductors assigned to several phases. A power semiconductor is, in particular, a transistor. For example, MOSFETs, IGBTs, and JFETs can be used as power semiconductors. Several identical or different power semiconductors can be used in an assembly or...They can be combined in a power semiconductor module. A power semiconductor is, in particular, a semiconductor switch. A power semiconductor typically has at least one gate terminal, one source terminal, and one drain terminal, and optionally a Kelvin source terminal. An electrical and thermal contact is a connection that conducts current and heat with low resistance. A planar contact is understood to be, in particular, a connection over a larger area or a relevant proportion of a total area. Specifically, a planar contact here is a contact without the use of a bond wire. A connector refers, in particular, to a contact structure that comprises at least three electrical conductors. These conductors are insulated from the environment and from each other. In particular, a laminated environment may be used.A connector can be, in particular, a cable or a (flexible) printed circuit board. Here, "orientation" refers specifically to a spatial orientation, which can be defined, for example, by the course of a central axis. A uniform orientation can thus correspond to an orientation with parallel central axes.

[0036] The invention is described and explained in more detail below with reference to some selected embodiments in conjunction with the accompanying drawings. These show: Fig. 1 a schematic representation of a vehicle with a power semiconductor module according to the invention in a traction converter; Fig. 2 a schematic representation of a semiconductor package in a power semiconductor module according to the invention; Fig. 3a, Fig. 3b Schematic representations of a use of two semiconductor packages in a half-bridge circuit in a power semiconductor module according to the invention; Fig. 4 a schematic perspective representation of an embodiment of a semiconductor package for use in a power semiconductor module according to the invention; Fig. 5 a schematic representation of the structure of an embodiment of the power semiconductor module according to the invention; Fig. 6 a schematic perspective representation of an embodiment of the power semiconductor module according to the invention; Fig. 7 a schematic top view of various arrangements of semiconductor packages in power semiconductor modules according to the invention; Fig. 8 a schematic representation of an embodiment of a power semiconductor module according to the invention; Fig. 9 a schematic representation of an embodiment of a power semiconductor module according to the invention; Fig. 10 a schematic representation of an embodiment of a power semiconductor module according to the invention; Fig. 11 a schematic representation of a power semiconductor module according to the invention; Fig. 12 a schematic representation of the structure of an embodiment of a power semiconductor module according to the invention consisting of two assemblies according to the invention; Fig. 13 a schematic representation of the structure of a further embodiment of a power semiconductor module according to the invention, consisting of two assemblies according to the invention; and Fig. 14 a schematic representation of a top view of the arrangement of several semiconductor packages in power semiconductor modules according to the invention.

[0037] In Fig. Figure 1 schematically depicts a vehicle 10 with a traction inverter 12. The traction inverter 12 is arranged between a battery 14 and an electric motor 16 of the vehicle 10 to convert the direct current of the battery 14 into the alternating current required by the electric motor 16. The traction inverter 12 comprises a power semiconductor module 18 according to the invention, which in turn comprises at least two semiconductor packages 20 arranged in a half-bridge circuit. Furthermore, a control unit 21 is provided for controlling the various semiconductors in the semiconductor packages 20, which is specifically connected to the corresponding gate terminals of the semiconductors.

[0038] The representation in Fig. Figure 1 is to be understood as a schematic side sectional view. In the illustrated embodiment, the power semiconductor module 18 comprises two semiconductor packages. It is understood that a traction converter 12 typically contains a plurality of power semiconductor modules, each with several semiconductor packages.

[0039] According to the invention, a semiconductor package 20 is used, which is designed in the manner of a CSP. In particular, the semiconductor package 20 according to the invention preferably comprises at most two individual power semiconductors (chips) and thus represents a unit in the size range of a single chip or a single power semiconductor.

[0040] In the Fig. Figure 2 schematically shows an embodiment of a semiconductor package 20 for use in a power semiconductor module according to the invention. The semiconductor package 20 comprises a power semiconductor 22, a first contact unit 24, a second contact unit 26, and a connector 28. The semiconductor package 20 is encapsulated with a potting compound 29. The illustration is to be understood as a side sectional view. The individual components are not shown to scale in terms of their dimensions, particularly their thickness. The thickness of a power semiconductor is typically in the range of a few hundred micrometers. The current-conducting components are often comparatively thicker. Therefore, the illustration should be understood as... Fig. 2 insofar as it essentially serves as a principle visualization.

[0041] The power semiconductor 22 corresponds to a chip and is essentially planar. The power semiconductor 22 has a first side 30, which corresponds to the top side in the illustration, and a second side 32, which corresponds to the bottom side in the illustration. A control terminal 34 is arranged on the first side 30, which corresponds in particular to the gate terminal of the power semiconductor 22. It is particularly advantageous that the semiconductor package 20 according to the invention does not require the use of planar insulating units. In particular, no insulating layers are required for electrical insulation between the first side 30 of the power semiconductor 22 and components in the direction of the first contacting unit 24. This enables improved thermal contacting as well as efficient manufacturing.

[0042] The first contact unit 24 is in electrical and thermal contact with the first side 30 of the power semiconductor 22. In the illustrated embodiment, the contact is planar and covers a large portion of the first side 30. The electrical and thermal contact thus extends over at least half of the first side 30, or the top surface, of the power semiconductor 22. Preferably, the first contact unit 24 is planar, covering more than 60%, 70%, or even 80% of the first side 30 of the power semiconductor 22. The first contact unit 24 connects the first side 30 of the power semiconductor 22 to a DC or AC side of a half-bridge circuit. The drain or source terminal of the power semiconductor 22 is contacted via the first contact unit 24.In addition to the electrical contact to the power line, a thermal path is also provided via the first contacting unit 24 to dissipate switching heat.

[0043] The second contact unit 26 is in contact with the second side 32 of the power semiconductor 22. The second contact unit 26 is also thermally and electrically contacted over a large area of ​​the second side 32 of the power semiconductor 22. Preferably, as shown in the illustrated embodiment, the entire second side 32 is in contact with the second contact unit 26.

[0044] In the illustrated embodiment, the first contacting unit 24 is designed as a rigid component. In particular, the contacting can be implemented via a copper block as the first contacting unit 24. However, in alternative embodiments, the use of a copper metallization layer as the first contacting unit 24 is also conceivable. For example, this can be achieved through a vapor deposition process. The second contacting unit 26 can also be designed as a rigid component. For example, a copper support (leadframe) can correspond to the second contacting unit 26.

[0045] In the illustrated embodiment, the contact between the first contacting unit 24 and the power semiconductor 22, and between the second contacting unit 26 and the power semiconductor 22, is implemented by means of a sintered connection 36. It is understood that, alternatively or additionally, a soldered connection or another connection technology can be used.

[0046] In the illustrated embodiment, the power semiconductor 22 includes an (optional) additional control terminal 38, which is also located on the first side 30 of the power semiconductor 22. This additional control terminal 38 can, for example, enable the connection of a Kelvin source terminal of the power semiconductor 22. In the illustrated example, the additional control terminal 38 is connected to the outside via the connector 28 (the connector thus includes two signal lines). Alternatively, it is also conceivable that the additional control terminal 38 is brought to the outside via another connector, such as a separate bond wire.

[0047] The connector 28 connects the control terminal 34 of the power semiconductor 22 to the control unit (outside the semiconductor package). In the illustrated embodiment, the connector 28 comprises a flexible printed circuit board (PCB) or is designed as such. A conductor track can be provided on the flexible PCB for contacting the control terminal of the power semiconductor 22, and another conductor track for contacting the additional control terminal 38. The connector 28 can thus act as a common connector, bringing both the control terminal 34 and the additional control terminal 38 to the outside, particularly via two conductor tracks. Furthermore, additional functions can be implemented in this embodiment based on further conductor tracks and, if necessary, additional components.It goes without saying that other connecting parts can also be used as connectors, for example a composite of several bond wires or another type of cable or another type of laminated composite.

[0048] An embodiment of the semiconductor package 20 is shown, in which the cross-sectional area of ​​the first contact unit 24 on the first side 30 of the power semiconductor 22 increases with increasing distance from the first side 30 of the power semiconductor 22, parallel to a plane of the power semiconductor 22. The cross-sectional area of ​​the first contact unit thus becomes larger, enabling improved heat dissipation. In the example shown, the change in cross-sectional area is implemented discretely in the form of a step. The change in cross-section is optional. It is understood that other changes in cross-section, for example a continuous change in cross-section, are also conceivable.

[0049] In comparison to previous approaches, the design of the semiconductor package 20 enables a CSP (Configurable Semiconductor Package) implementation. This means that only the minimum number of components required is used. A power semiconductor module can be constructed from several semiconductor packages 20 according to the invention. This results in great design flexibility, as different numbers of semiconductor packages can be used together. Furthermore, the shape of the power semiconductor module can be adapted with comparatively little effort, since rearranging several semiconductor packages is easily accomplished due to their individual design.

[0050] In the Fig. 3a and Fig. Figure 3b shows that the semiconductor package 20 can be used in a power semiconductor module according to the invention by rotating it by 180° while otherwise maintaining an identical design, on a low-side or high-side of a half-bridge circuit. Regarding the reference numerals in the Fig. 3a and Fig. 3b and also in the following figures, reference is made to the above statements regarding Fig. Reference 2. The same reference numerals denote the same components; figure areas with identical hatching may correspond to the same components. To avoid repetition and improve clarity, all reference numerals are not reintroduced and drawn in the figures. In particular, the differences between the various embodiments and the resulting variations are discussed.

[0051] The depictions in the Fig. 3a and Fig. It can be seen from Figure 3b that the semiconductor package 20 enables a three-dimensional structure of a power semiconductor module according to the invention. In particular, a type of stacking can be enabled in which semiconductor packages 20 are used in a power semiconductor module, one half of which is rotated by 180° relative to a second half. A rotation by 180° is understood to mean, in particular, the use of an otherwise identically designed semiconductor package in a reversed orientation, as shown in the illustration. Thus, for example, one half of the semiconductor packages in a power semiconductor module can be arranged as shown in the illustration. Fig. 3a should be aligned, while the other half should be aligned according to the representation in Fig. 3b is aligned. The option of using or installing in a modified orientation allows for simplified manufacturing of power semiconductor modules from multiple semiconductor packages, as well as flexibility regarding the shape of the power semiconductor module. Furthermore, efficient manufacturing can be achieved.

[0052] In the Fig. Figure 4 schematically shows a perspective view of a semiconductor package 20 for use in a power semiconductor module according to the invention. The arrangement of the power semiconductor 22 between the first contact unit 24 and the second contact unit 26 is shown in particular. For clarity, the potting compound typically used is not shown in the illustration. A source contact can be established via the first contact unit 24, for example. A drain contact can be established via the second contact unit 26, for example. In the illustrated embodiment, an embodiment is shown in which the power semiconductor 22 has a control terminal 34 and a further control terminal 38, which are connected to the control unit 21 of the traction converter via two bond wires as connectors 28 and further connectors 40, respectively.It goes without saying that other types of contact are also conceivable. For example, a laminated flexible film, in particular a flexible printed circuit board, can be used for contacting, which has corresponding conductive traces and leads both contacts from the power semiconductor module to the control unit.

[0053] In Fig. Figure 5 shows an embodiment of the power semiconductor module 18 according to the invention. A side sectional view is shown. The view reveals that the half-bridge circuit is composed of a total of four semiconductor packages 20, two of which are arranged in parallel. Thus, two parallel-connected semiconductor packages 20 are arranged on both the high-side (DC+) and the low-side (DC-). In the illustrated embodiment, the four semiconductor packages are arranged in one plane. Further power semiconductor modules 18 can be arranged in front of or behind this plane.

[0054] An embodiment is shown in which a semiconductor package 20 (or two semiconductor packages) on the high-side is arranged rotated by 180° relative to a semiconductor package 20 (or two semiconductor packages) on the low-side. The two semiconductor packages 20 on the left side of the illustration are, so to speak, upside down.

[0055] Furthermore, in the illustrated embodiment, the two parallel-connected semiconductor packages 20 are each arranged rotated or mirrored relative to each other such that a control element, i.e., a contact point for the connector or the further connector for connection to the control unit, is centrally located in each case. In the illustrated embodiment, this control layer 42 is designed as a laminated flexible film with corresponding conductive traces.

[0056] The first contact units (shown below) of the two semiconductor packages 20 on the right side (low-side) and the two second contact units (shown below) of the two semiconductor packages 20 on the left side (high-side) each form an AC output and are electrically contacted via a common AC contact 44. In particular, this common AC contact 44 can be a busbar or a body made of a conductive material. The second contact units (shown above) of the semiconductor packages 20 on the right side (low-side) and the two second contact units (shown below) of the semiconductor packages 20 on the left side (high-side) are connected via a common AC contact 44.The first contact units (in the illustration above) of the power semiconductors of the semiconductor packages 20 on the left side (high-side) form a DC input and are connected in the illustrated embodiment via a DC contact 46a, 46b to two poles of a DC voltage source 48 (in particular a battery of an electric vehicle).

[0057] Sintered connections (not shown) can be arranged in particular between the DC contacts 46a, 46b and the semiconductor packages 20 or between the AC contact 44 and the semiconductor packages 20.

[0058] In the illustrated embodiment, the power semiconductors in the semiconductor packages 20 are cooled via a common external heat sink 50, and thus exclusively on the side of the AC contact 44. In the illustrated embodiment, an insulating layer 52 is arranged between the AC contact 44 and the external heat sink 50.

[0059] In Fig. Figure 6 is a perspective view of the embodiment from Fig. Figure 5 shows that an arrangement of six semiconductor packages 20 each is connected in parallel on the high-side and the low-side. Furthermore, the power semiconductor module 18 shown comprises twelve semiconductor packages 20 each for each of the three phases AC-U, AC-V, AC-W of an electric motor. Referring to Fig. There are 5 in the direction of the drawing plane in Fig. 5, that is, three times four semiconductor packages per phase with three phases.

[0060] The external heat sink 50 in Fig. 6 is arranged as a common external heat sink for all three phases below the semiconductor packages 20. The electrical contacting is carried out, for example, via three busbars for the AC contacting 44 (for the three phases AC-U, AC-V, AC-W), a common busbar for the high-side DC contacting 46a and three busbars for the low-side DC contacting 46b.

[0061] In Fig. Figure 7 is a schematic bird's-eye view of three different embodiments of the [description of the element]. Fig. 5 and Fig. Figure 6 illustrates the concept of the arrangement of the various semiconductor packages 20. Only one arrangement for each phase is shown. On the left is an embodiment of the power semiconductor module in which a total of six semiconductor packages 20 are provided, three of which form a high-side switch and three of which form a low-side switch in the half-bridge circuit. In the middle is an embodiment in which five semiconductor packages 20 are provided for the low-side and five for the high-side switches. On the right is an embodiment in which six semiconductor packages 20 are provided for the low-side and six for the high-side. The contacting is carried out according to the diagram in Figure 6. Fig. 5 and Fig. The principle shown in 6. Fig. The embodiment shown in section 6 corresponds in this respect to an implementation of the one shown on the right-hand side in Fig. The principle shown in Figure 7 uses six semiconductor packages 20 in parallel for the high and low sides. This arrangement concept enables efficient scalability, with the current increasing progressively from left to right in the illustration of the embodiment. The current scales, so to speak, with the number of semiconductor packages 20 used.

[0062] In Fig. Figure 8 shows an embodiment of a power semiconductor module 18 according to the invention, in which a semiconductor package 20 is arranged as a switch in the corresponding half-bridge circuit for each of the three phases AC-U, AC-V, and AC-W of an electric motor. It is understood that in this embodiment, too, several semiconductor packages can be arranged in the direction of the plane of the drawing and, for example, connected in parallel. The DC contacts 46a and 46b for the high and low sides, respectively, are located on the outer sides (top and bottom). The AC contacts 44 for the three phases AC-U, AC-V, and AC-W are located in the center. In the illustrated embodiment, the control is implemented via a control layer 42, which runs on the AC voltage side.In the illustrated embodiment, the power semiconductors of each of the two semiconductor packages 20 of a phase (the two switches of the half-bridge circuit) are aligned parallel to each other and arranged in different planes. In the illustrated embodiment, the semiconductor packages 20 are aligned in this respect. The two outer heat sinks 50 are thermally contacted and, in the illustrated embodiment, electrically insulated by an insulating layer 52. In each half-bridge circuit, a first contact unit of one semiconductor package and a second contact unit of the other semiconductor package each form an AC output, which is then electrically connected via a common AC contact 44. The connection can be made, for example, by means of sintered connections.

[0063] The in Fig. The embodiment of the power semiconductor module 18 shown in Figure 9 differs from the one previously described in Figure 9 in that it differs from the embodiment shown ... shown in Figure 9 in that shown Fig. The embodiment shown in Figure 8 differs in that the control layer 42 is arranged on the AC side. Otherwise, the embodiments are identical in this respect.

[0064] In Fig. Figure 10 shows an embodiment which supplements the previously described Fig. In the embodiment shown in Figure 8, an intermediate heat sink 54 is arranged between each pair of semiconductor packages 20. The insulation of the intermediate heat sink 54 from the AC contacts and from the three phases AC-U, AC-V, AC-W is provided by an insulating layer 52. In the illustrated embodiment, Fig. 10 the control is implemented by means of a control layer 42 on the DC side.

[0065] In Fig. Figure 11 shows an embodiment of the power semiconductor module 18 according to the invention, in which, as before, an intermediate heat sink 54 is arranged between each of the switches of the half-bridge circuit and is insulated by means of an insulating layer 52. In comparison to the embodiment in Fig. 10 the control layer 42 is located on the AC side.

[0066] In Fig. Figure 12 shows an approach for constructing a power semiconductor module 18 according to the invention from two assemblies 56a, 56b. In the illustrated embodiment, each assembly 56a, 56b comprises three semiconductor packages 20 and a common outer heat sink 50. In the upper part of Fig. Figure 12 shows the two assemblies 56a and 56b still separate. The lower part shows the power semiconductor module 18 when the two assemblies 56a and 56b are connected. For example, an electrically conductive adhesive 58 can be used to connect the two assemblies 56a and 56b. The output to the corresponding phase of the electric motor can be implemented via a suitable AC contact 44. Prefabrication of the assemblies 56a and 56b enables an efficient manufacturing process. The electrically conductive adhesive 58 can also compensate for manufacturing tolerances.

[0067] In Fig. 13 refers to Fig. Figure 12 shows a corresponding embodiment in which an intermediate heat sink 54 is additionally provided between the two assemblies 56a, 56b. The intermediate heat sink can also be connected to the two assemblies 56a, 56b by means of two layers of electrically conductive adhesive 58. The DC contact 46a, 46b for the two sides of the half-bridge circuit is provided for the upper and lower assemblies 56a, 56b, respectively.

[0068] In Fig. Figure 14 schematically shows an arrangement of several semiconductor packages 20 in power semiconductor modules 18 according to the invention. The illustration is to be understood as a bird's-eye view. The arrangement or topology can be particularly relevant to the design described in the Fig. The embodiments shown in sections 8 to 13 correspond to this. On the left side in Fig. Figure 14 shows that in variants A, B, C, and D, depending on the required current, four, six, eight, or ten identical semiconductor packages 20 can be connected in parallel. Only the low-side (or high-side) switches are visible. On the right side in Fig. Figure 14 shows that scaling with 3, 4, 5 or 6 parallel semiconductor packages is also possible.

[0069] The invention has been comprehensively described and explained with reference to the drawings and the description. The description and explanation are to be understood as examples and not as limiting. The invention is not limited to the disclosed embodiments. Other embodiments or variations will become apparent to a person skilled in the art when using the present invention and upon a detailed analysis of the drawings, the disclosure, and the subsequent claims.

[0070] In the claims, the words "comprise" and "with" do not preclude the presence of further elements or steps. The undefined article "a" or "an" does not preclude the presence of multiple elements. A single element or unit can perform the functions of several of the units mentioned in the claims. An element, unit, interface, device, and system can be implemented partially or completely in hardware and / or software. The mere mention of some measures in several different dependent claims is not to be understood as precluding the advantageous use of a combination of these measures. Reference numerals in the claims are not to be interpreted restrictively. Reference sign 10 vehicles 12 traction converters 14 batteries 16 electric machines 18 Power semiconductor module 20 semiconductor package 21 Control unit 22 Power semiconductors 24 first contacting unit 26 second contacting unit 28 connectors 29 Potting compound 30 first page 32 second page 34 Control connection 36 Sintered joint 38 additional control connections 40 additional connectors 42 Control layer 44 AC contact 46a, 46b DC contact 48 DC voltage source 50 external heat sinks 52 Insulating layer 54 Intermediate cooling elements 56a, 56b assembly 58 electrically conductive adhesive QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2022 202 254 A1

[0004]

Claims

[1] Power semiconductor module (18) for a traction converter (12), comprising at least two identical semiconductor packages (20) arranged as switches in a half-bridge circuit, the semiconductor packages each comprising: a power semiconductor (22) with a first side (30), an opposite second side (32) and a control terminal (34) on the first side; a first contacting unit (24) for contacting the first side, which is thermally and electrically contacted over a large part of the first side; a second contacting unit (26) for contacting the second side, which is thermally and electrically contacted over a large area of ​​the second side; and a connector (28) for connecting the control terminal of the power semiconductor to a control unit (21). [2] Power semiconductor module (18) according to claim 1, wherein the power semiconductors (22) of the two semiconductor packages (20) are aligned parallel to each other and are arranged in different planes, in particular in alignment. [3] Power semiconductor module (18) according to claim 2, with two external heat sinks (50) which are arranged on both sides of the two semiconductor packages (20) with respect to the planes of the power semiconductors (22) and are each thermally contacted with the contacting unit (24, 26) of one semiconductor package facing away from the other semiconductor package, wherein the external heat sinks are preferably each electrically insulated from the semiconductor packages by means of an insulating layer (52), in particular an insulating film. [4] Power semiconductor module (18) according to one of claims 2 and 3, with an intermediate heat sink (54) arranged between the two semiconductor packages (20) and thermally contacted with the contacting unit (24, 26) of one semiconductor package facing the other semiconductor package, wherein the intermediate heat sink is preferably electrically insulated from the semiconductor packages by means of an insulating layer (52), in particular an insulating film. [5] Power semiconductor module (18) according to one of the preceding claims, wherein the two semiconductor packages (20) are aligned in the same direction such that a first side of the power semiconductor (22) of one semiconductor package is aligned in the same direction as a first side of the power semiconductor of the other semiconductor package. [6] Power semiconductor module (18) according to claim 5, wherein a first contact unit (24) of one semiconductor package (20) and a second contact unit (26) of the other semiconductor package each form an AC output and are electrically contacted via a common AC contact (44); and The AC contacting is preferably arranged between the semiconductor packages and / or is electrically contacted by means of sintered connections with the first contacting unit of one semiconductor package and the second contacting unit of the other semiconductor package. [7] Power semiconductor module (18) according to one of claims 1 to 4, wherein the two semiconductor packages (20) are arranged rotated by 180° relative to each other, such that a first side of the power semiconductor (22) of one semiconductor package is oriented in the same direction as a second side of the power semiconductor of the other semiconductor package. [8] Power semiconductor module (18) according to one of the preceding claims, comprising at least six identical semiconductor packages (20), wherein two semiconductor packages are arranged as switches in three half-bridge circuits for three phases of an electric motor. [9] Power semiconductor module (18) according to one of the preceding claims, comprising at least four identical semiconductor packages (20), wherein at least two identically aligned semiconductor packages are arranged in a parallel circuit and together form a switch in the half-bridge circuit. [10] Power semiconductor module (18) according to any one of the preceding claims, wherein a second side of the power semiconductor (22) of one semiconductor package (20) and a first side of the power semiconductor of the other semiconductor package each form a DC input and are oriented away from each other; and the DC inputs are each connected via a DC contact (46a, 46b) to two poles of a DC voltage source (48). [11] Assembly (56a, 56b) for a power semiconductor module (18) according to one of the preceding claims, comprising: at least two identical and aligned semiconductor packages (20) in a parallel circuit, which together form a switch in the half-bridge circuit; a common external heat sink (50) which is thermally contacted with the first contacting units (24) of the parallel-connected semiconductor packages; a common AC contact (44) which is electrically contacted with the second contact units (26) of the parallel-connected semiconductor packages; and a common DC contact point that is electrically contacted with the first contacting units of the parallel-connected semiconductor packages. [12] Power semiconductor module (18) with two assemblies (56a, 56b) according to claim 11, wherein the two assemblies are connected to each other on their sides facing away from the external heat sinks (50), preferably via an electrically conductive and tolerance-compensating adhesive (58). [13] Traction converter (12) for a vehicle, with: a power semiconductor module (18) according to one of claims 1 to 11 or 12 or with two assemblies (56a, 56b) according to claim 11; and a control unit (21) for controlling the power semiconductors (22) via their control connections. [14] Traction converter (12) for a vehicle with three power semiconductor modules (18) according to one of claims 1 to 10 and 12, which are assigned to three phases of an electric motor.

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