Power Components, Power Submodules, and Power Modules

Abstract

A power component (100) comprises a power semiconductor device (1) having a top surface (10) and a bottom surface (12), an electrical insulator (2) surrounding the power semiconductor device, and a first contact element (3) and a second contact element (4) both in electrical contact with the power semiconductor device. Each of the first and second contact elements has a terminal area (30, 40) for electrically contacting the power component with the outside world via the contact element. The power component is configured for operation with the first and second contact elements located at different electrical potentials. The terminal areas of the first and second contact elements are located on the same side of the power semiconductor device but at different heights relative to the top surface of the power semiconductor device.

Description

[Technical field]

[0001] The present disclosure relates to a power component, a power sub-module, and a power module. Further, the present disclosure relates to a method for manufacturing a power sub-module and a power module. [Background technology]

[0002] DE 10 2016 125 657 A1 relates to a method for producing an electronic assembly, in which a circuit arrangement is pressed onto at least two contact stamps, whereby the circuit arrangement is in each case plastically deformed by pressing and the contact stamps are electrically conductively connected to one another by the circuit arrangement, and an electrically conductive connection is then created between the contact stamps and first load electrodes of the respective semiconductor chips of the electronic assembly assigned to them. Summary of the Invention [Problem to be solved by the invention]

[0003] What is needed is an improved power component, for example a power component that simplifies the electrical interconnection of several such power components to a power sub-module or power module. What is further needed is an improved power sub-module and an improved power module, both of which include at least one such power component. What is further needed is a method for manufacturing such a power sub-module and such a power module. [Means for solving the problem]

[0004] SUMMARY OF THE DISCLOSURE Embodiments of the present disclosure relate to improved power components, improved power sub-modules, and improved power modules. Further embodiments relate to methods for the manufacture of such power sub-modules and for the manufacture of such power modules.

[0005] First, the power components are defined. According to one embodiment, a power component comprises a power semiconductor device having a top surface and a bottom surface, an electrical insulator surrounding the power semiconductor device, and first and second contact elements, both in electrical contact with the power semiconductor device. Each of the first and second contact elements has a terminal area for electrically contacting the power component with the outside world through the contact element. The power component is configured for operation with the first and second contact elements located at different electrical potentials. The terminal areas of the first and second contact elements are located on the same side of the power semiconductor device but at different heights relative to the top surface of the power semiconductor device.

[0006] A power module or power sub-module typically comprises several power semiconductor devices connected in series and / or parallel to achieve a desired power rating. These power devices are typically bonded to an (insulating) substrate (e.g. fabricated from a ceramic material with top and bottom metallization layers) and the drain pads of the devices are connected to the top metallization layer of the substrate (die bonding). The upper gate and source pads of the devices are then connected by heavy Al wire bonds to different pads on the top metallization layer of the substrate. The top-side connections by wire bonds limit the reliability and lifetime of such power (sub)modules, an issue that is gaining importance with the higher current densities and higher operating temperatures of wide bandgap semiconductors such as SiC and GaN.

[0007] For this reason, novel top-side interconnect methods have been developed, such as heavy Cu wire bonding or soldering or sintering solid clips or lead frames. However, these methods require a robust metallization layer on the top side of the power semiconductor device. The bond buffer introduces additional material and processing costs as well as additional reliability concerns.

[0008] The present invention solves these problems, among others: because the terminal areas are located at different heights, i.e. in unique planes, a reliable interconnection for a subsequent packaging process, for example to form a power module or power sub-module, is facilitated.

[0009] The terms "top" and "bottom" should not be understood to be limited to directions along the direction of gravity. Rather, they may be used to characterize opposite sides or opposite directions, etc.

[0010] The power semiconductor device is, for example, a power semiconductor chip. It may also be a power semiconductor switch. The power component may comprise exactly one power semiconductor device or a number of power semiconductor devices, for example electrically connected to each other. The power semiconductor device comprises at least one, for example exactly one, semiconductor body. The semiconductor body may be made of Si or SiC or diamond or GaN.

[0011] The electrical insulator may be an encapsulant. For example, the insulator is manufactured by transfer molding, such as film assisted transfer molding, or compression molding, or injection molding. The electrical insulator may electrically insulate the first and second contact elements from each other. The insulator may include or consist of a thermoplastic or a thermosetting plastic. For example, the insulator is made of a resin, for example with additional filler material. The insulator may be integrally formed.

[0012] The insulator surrounds the power semiconductor device at least laterally, i.e. in a direction parallel to the top and / or bottom surface. In the laterally direction, the power semiconductor device may be completely surrounded by the insulator. This allows the insulator to be in direct contact with the power semiconductor device and to form-fit or conformally surround the power semiconductor device. That is, the power semiconductor device may be embedded in the electrical insulator.

[0013] The top and bottom surfaces of the power semiconductor device are major surfaces of the device, e.g., parallel to a plane of the main extent of the power semiconductor device. Each of the first and second contact elements may be in electrical contact with the top surface. The bottom surface of the power semiconductor device is opposite the top surface. The thickness of the power semiconductor device, measured as the distance between the top and bottom surfaces, may be less than the lateral extent of the top and bottom surfaces, measured along the top or bottom surface. The top and bottom surfaces of the power semiconductor device are, e.g., partially formed by a semiconductor body of the power semiconductor device.

[0014] Each of the first and second contact elements has a terminal area that is expected to electrically contact the contact element with the outside and thus the power component with the outside by the contact element. The terminal area is not covered by an electrical insulator. In the unmounted or unassembled state of the power component, the terminal area may be exposed, i.e. freely accessible. The terminal area is, for example, a surface of the contact element. The surface may be a flat surface. The first and / or second contact elements may each be integrally formed or each may be formed from several parts. Each of the first and second contact elements is, for example, formed from a metal, such as Al or Cu. For example, the first contact element and / or the second contact element is a solid metal block.

[0015] The first and second contact elements are arranged on the same side of the power semiconductor device. This means that in the vertical direction from the bottom side to the top side of the power semiconductor device, the terminal areas of the first and second contact elements are both located at the front or rear of the power semiconductor device. For example, both terminal areas are located at the top side, i.e., at the rear in the vertical direction of the power semiconductor device.

[0016] The terminal areas of the first and second contact elements are arranged at different heights relative to the top surface. For example, the height difference is at least 50 μm, or at least 100 μm, or at least 300 μm. The terminal area of ​​the first contact element may be arranged at a higher position than the terminal area of ​​the second contact element.

[0017] According to a further embodiment, the first and / or second contact elements and / or the power semiconductor device are embedded in the insulator. This means that the contact elements and / or the power semiconductor device are conformally or form-fittingly surrounded by the insulator at least in the lateral direction. For example, the contact elements extend from the top surface through the insulator.

[0018] According to further embodiments, the power component is a component of a chip-scale package. For example, the footprint of the power component is at most 50% or at most 30% larger than the footprint of the power semiconductor device. The footprint of the power semiconductor device is, for example, primarily determined by the footprint of its semiconductor body. For example, at least 90% of the footprint of the power semiconductor device is due to its semiconductor body.

[0019] According to a further embodiment, the first and / or second contact elements protrude from the electrical insulator. The respective terminal areas may therefore be located outside the insulator and offset with respect to the outer surface of the insulator causing the contact elements to protrude. Alternatively, the first and / or second contact elements may end flush with the outer surface of the insulator. The respective terminal areas may therefore be flush with the outer surface of the insulator. The first and / or second contact elements may protrude from the insulator by at least 10 μm or at least 50 μm and / or by up to 500 μm. For example, the first and second contact elements leave the insulator at different heights with respect to the top surface of the power semiconductor device.

[0020] According to a further embodiment, the first contact element protrudes from or ends flush with an upper surface of the insulator, which is for example at least partially parallel to an upper surface of the power semiconductor device, and which is arranged behind the power semiconductor device in the vertical direction.

[0021] According to a further embodiment, the terminal area of ​​the first contact element faces away from the power semiconductor device, for example the terminal area of ​​the first contact element extends parallel to the top surface of the insulator.

[0022] According to further embodiments, the area of ​​the terminal region of the first contact element is at least 20%, at least 40% or at least 50% of the area of ​​the top surface of the power semiconductor device. The area of ​​the terminal region of the second contact element is, for example, at least 10%, at least 30% or at least 40% of the area of ​​the top surface of the power semiconductor device. Such a large area of ​​the terminal region simplifies the electrical connection to the outside.

[0023] According to further embodiments, the second contact element protrudes from a side surface of the insulator or from a top surface of the insulator. Alternatively, the second contact element may terminate flush with the side surface or top surface of the insulator. A side surface is a surface that extends obliquely or perpendicularly to the power semiconductor device or the top surface of the insulator.

[0024] A configuration in which the first contact element protrudes from the top surface of the insulator or ends flush with the top surface of the insulator and the second contact element protrudes from the side surface of the insulator can increase the creepage distance between the first contact element and the second contact element.

[0025] According to a further embodiment, the top surface of the insulator comprises a first portion and a second portion arranged at different heights relative to the top surface of the power semiconductor device. A step may be formed between the first portion and the second portion. For example, the second portion is located at a lower height relative to the top surface of the power semiconductor device than the first portion. The height difference may be at least 50 μm, or at least 100 μm, or at least 300 μm.

[0026] According to a further embodiment, the terminal area of ​​the first contact element is arranged in the area of ​​the first part. This means that in a top plan view, the terminal area of ​​the first contact element may be arranged inside the first part of the insulator. The first contact element may protrude from the first part. The terminal area of ​​the second contact element may be arranged in the area of ​​the second part of the insulator. The second contact element may protrude from the second part.

[0027] The two-part insulator top surface configuration can increase the creepage distance between the first and second contact elements.

[0028] According to a further embodiment, the power component further comprises a third contact element in electrical contact with the power semiconductor device. The third contact element may contact the power semiconductor device and / or its semiconductor body at a bottom side.

[0029] According to a further embodiment, the third contact element comprises a terminal area for electrically contacting the power component with the outside via the third contact element. The terminal area of ​​the third contact element is not covered by an insulator. This terminal area may be exposed in an unmounted or unassembled state of the power component. The power component is configured, for example, to operate with the third contact element at a different potential than the first and / or second contact elements.

[0030] According to a further embodiment, the terminal area of ​​the third contact element is arranged at a different height with respect to the top side of the power semiconductor device than the terminal areas of the first and second contact elements. For example, the third contact element and / or its terminal area is arranged on a different side of the power semiconductor device than the terminal areas of the first and second contact elements. For example, the terminal area of ​​the third contact element and / or the third contact element itself is arranged on a bottom side of the power semiconductor device. Thus, in the vertical direction, the terminal area of ​​the third contact element and / or the third contact element itself is arranged in front of the power semiconductor device.

[0031] The third contact element may be formed of a metal such as Al or Cu. For example, the third contact element is a lead frame. The third contact element may be formed in one piece or in several parts. The third contact element may be, for example, a substrate having a top metallization and a bottom metallization and an insulating layer between the top and bottom metallizations, for example made of a polymer or ceramic.

[0032] According to a further embodiment, the terminal area of ​​the third contact element faces away from the power semiconductor device. For example, the terminal area of ​​the third contact element may be a surface, for example a flat surface. It may extend parallel to the bottom surface of the power semiconductor device and / or parallel to the terminal area of ​​the first contact element. It may face in an opposite direction to the terminal areas of the first and / or second contact elements.

[0033] According to a further embodiment, the power semiconductor device is an electrical switch, for example a transistor.

[0034] According to a further embodiment, the first and second contact elements are electrically connected to main electrodes of a power semiconductor device, for example the cathode and anode of the power semiconductor device.

[0035] According to a further embodiment, the second contact element is connected to an auxiliary electrode of the power semiconductor device, the auxiliary electrode being, for example, a gate electrode.

[0036] According to a further embodiment, the power semiconductor device is one of a MOSFET, a MISFET, an IGBT, a BIGT, or a thyristor.

[0037] According to a further embodiment, the first contact element is connected to a source electrode or an emitter electrode of the power semiconductor device. The second contact element may be connected to a gate electrode of the power semiconductor device. The third contact element may be connected to a drain electrode or a collector electrode of the power semiconductor device. For example, the source / emitter electrode and the gate electrode are located on a top surface of the power semiconductor device, and the drain / collector electrode is located on a bottom surface of the power semiconductor device.

[0038] Next, the power sub-module is defined. According to one embodiment of the power submodule, the power submodule comprises at least one power component according to any one of the embodiments described herein. The power submodule further comprises an electrically conductive cooling element. The power component is disposed on the cooling element, e.g., attached to the cooling element, and electrically connected to the cooling element. The cooling element comprises a cooling structure for cooling the power semiconductor device. The cooling element further comprises a terminal area facing away from the power semiconductor device. The terminal area of ​​the cooling element is configured to electrically contact the submodule with the outside via the cooling element.

[0039] The cooling element may be a busbar. The cooling element may be made of a metal, for example Cu. The cooling element may be a carrier for a power submodule and may carry at least one power component. The cooling element may be formed in one piece. The cooling element may be a continuous body.

[0040] At least one power component is, for example, attached to a top surface of the cooling element, the opposite bottom surface of which forms the terminal area. The cooling element may have a larger lateral extent, measured parallel to the plane of main extent of the cooling element, than the power component. With respect to the submodule, the lateral direction is understood to be the direction parallel to the plane of main extent of the cooling element.

[0041] The terminal area of ​​the cooling element is foreseen to be in electrical contact with the power submodule or the power component via the cooling element. For example, the submodule is configured to operate with the cooling element at a different potential than the first and second contact elements. In the unassembled or unattached state of the power submodule, the terminal area of ​​the cooling element may be exposed, i.e. freely accessible. The same may apply to the terminal areas of the first and / or second contact elements of the power component.

[0042] The cooling element may be electrically connected to a third contact element of the power component, for example with a terminal area of ​​the third contact element facing the top surface of the cooling element.

[0043] According to a further embodiment, the terminal areas of the first contact element and the cooling element face away from the power semiconductor device and in opposite directions. For example, both terminal areas are flat surfaces that extend essentially parallel to each other. Facing the terminal areas in opposite directions allows at least two such power submodules to be stacked on top of each other for a series electrical connection of the two power submodules.

[0044] Such a series connection is possible without the spring contact elements typically used in stacked power submodules, which improves thermal performance since the heat can also be carried away by the first contact element that contacts the cooling element of the adjacent power submodule.

[0045] The simple stacking of power submodules without spring contacts is a result, among other things, of the terminal areas of the first and second contact elements being located at different heights, since a complex unraveling of the contact elements is avoided. As a result of the electrical insulator surrounding the power semiconductor device, even if the device is destroyed, the semiconductor material cannot escape laterally, so that electrical contact between the first contact element on the top side and the cooling element on the bottom side is always maintained.

[0046] According to a further embodiment, the cooling structure is or comprises a cooling channel or several cooling channels for guiding a cooling fluid through the cooling element. Additionally or alternatively, the cooling structure may be or comprise an arrangement of several cooling ribs and / or an arrangement of several cooling pin fins.

[0047] The cooling channel may have several bends. For example, the cooling channel may be S-shaped or serpentine. The cooling channel may extend from one side end of the cooling element to the other side end.

[0048] The cooling channels may be, for example, microchannels with a channel diameter of less than 1 mm. Alternatively, the channel diameter is greater than 1 mm. The cooling fluid may be a liquid or a gas.

[0049] The inlets and / or outlets of the cooling channels may each be located on a side of the cooling element. For example, the inlets and outlets may be arranged such that two power submodules can be fluidly connected in series such that the outlet of one submodule is aligned with the inlet of the other submodule to form a fluid connection between the individual cooling channels. Alternatively, the cooling elements of the two power submodules may be fluidly connected in parallel such that the inlets can be supplied with cooling fluid of the same temperature.

[0050] According to a further embodiment, the at least one power component is joined to the cooling element, for example by sintering, welding, soldering or gluing. A joining layer, such as a solder layer or a welded layer or a sintered layer or an adhesive layer, is formed, for example, between the terminal area of ​​the third contact element and the cooling element. As an example, only a joining layer is formed between the third contact element and the cooling element.

[0051] According to a further embodiment, the sub-module comprises at least two power components according to any of the embodiments described herein. The at least two power components of the sub-module are, for example, mounted on a cooling element, e.g. laterally adjacent to each other and laterally spaced apart from each other. The cooling element may thus extend over the power components. All features disclosed herein and below in relation to one power component of the sub-module are also disclosed for the other power components of the sub-module. In particular, all power components may be electrically connected to the cooling element in the same way.

[0052] According to a further embodiment, the at least two power components are embedded in a common encapsulant. For example, the common encapsulant may be a thermoplastic or thermosetting plastic, e.g. a resin. The common encapsulant may be manufactured by molding, e.g. injection molding or transfer molding or compression molding.

[0053] The common encapsulation is different from the electrical insulator mentioned above. A common encapsulation is assigned to several power components, while each power component is assigned an individual electrical insulator. The common encapsulation may be in direct contact with the electrical insulators of the power components. However, as a result, an interface is formed between the electrical insulators and the common encapsulation, which indicates that the electrical insulators and the common encapsulation were produced independently of each other.

[0054] According to at least one embodiment, the second contact elements of at least two power components are electrically connected to each other, for example via a connection element, also referred to herein as a second connection element. The second connection element may be in direct mechanical contact with the terminal area of ​​the second contact element. For example, the second connection element is a lead frame or a rigid or flexible circuit board.

[0055] According to a further embodiment, the second connecting element is embedded in the common enclosure. The second connecting element may be led out of the common enclosure, for example at a side of the common enclosure.

[0056] According to a further embodiment, the common encapsulation, for example its upper surface, ends flush with the terminal area of ​​the first contact element.

[0057] Next, the power module is defined. According to one embodiment of the power module, the power module comprises several, i.e. two or more, power components according to any one of the embodiments described herein, the power components being electrically connected to each other.

[0058] For example, the power components are electrically connected in parallel and / or in series. One or more power components may be part of a respective power sub-module according to any of the embodiments described herein. Thus, a power module may comprise two or more power sub-modules electrically connected to each other, for example, in series and / or in parallel.

[0059] The power module may be configured to handle currents in excess of 10 A. The power module may be a low voltage module configured to handle voltages below 1 kV, or may be a medium voltage module configured to handle voltages between 1 kV and 30 kV.

[0060] According to a further embodiment, the power module comprises a first connection element electrically connected to the first contact elements of the at least two power components, i.e. the first contact elements of the at least two power components are electrically connected to each other via the first connection element.

[0061] The first connection element may be adjacent to the terminal areas of the first contact elements of the at least two power components. The first connection element may be a bus bar or a lead frame terminal, or a rigid or flexible circuit board. The first connection element may be a cooling element as described above. Thus, all features disclosed for the cooling element are also disclosed for the first connection element and vice versa. For example, the first connection element is a cooling element of a further power submodule.

[0062] According to a further embodiment, the power module comprises a second connection element electrically connected to the second contact elements of the at least two power components, i.e. the second contact elements of the at least two power components are electrically connected to each other via the second connection element.

[0063] The second connection element may be adjacent to the terminal area of ​​the second contact element, for example, the second connection element may be a bus bar or lead frame terminal, or a rigid or flexible circuit board.

[0064] According to a further embodiment, with respect to the top sides of the power semiconductor devices of the at least two power components, the power semiconductor devices of the at least two power components are arranged at the same height.

[0065] According to a further embodiment, the first and the second connection elements are arranged at different heights with respect to the top sides of the power semiconductor devices of the at least two power components.

[0066] Two elements located at the same height in relation to a flat surface, such as the top surface of a power semiconductor device, means in this specification, for example, that a plane extending parallel to this surface intersects both elements, whereas two elements located at different heights means, for example, that each plane parallel to this surface and intersecting one of the two elements does not intersect the other of the two elements.

[0067] According to a further embodiment, the power module comprises a third connection element electrically connected to the third contact elements of the at least two power components, i.e. the third contact elements of the at least two power components are electrically connected to each other via the third connection element.

[0068] The third connection element may be a bus bar or lead frame terminal, or a rigid or flexible circuit board. For example, the third connection element may be a cooling element. For example, the third connection element may be a cooling element as described above. Thus, all features described with respect to the cooling element are also disclosed for the third connection element, and vice versa.

[0069] According to a further embodiment, at least two power components are stacked on top of one another. The stacked power components are, for example, connected in series. For example, a terminal area of ​​a first contact element of at least one of the stacked power components faces and is electrically connected to a terminal area of ​​a third contact element of a next one of the stacked power components. Here and below, "next power component" means the next power component in the direction of stacking.

[0070] According to at least one embodiment, at least two power sub-modules according to any of the embodiments described herein are stacked together, for example, the at least two stacked sub-modules are connected in series.

[0071] According to at least one embodiment, at least two stacked power submodules are stacked such that a terminal area of ​​a first contact element of at least one of the stacked power submodules faces and is electrically connected to a terminal area of ​​a cooling element of a next power submodule of the stacked power submodules.

[0072] According to a further embodiment, the cooling element is arranged on and in electrical contact with the terminal area of ​​the first contact element of the last power component or power submodule of the stacked power components or power submodules, where "last power component or power submodule" means the last power component or power submodule in the stacking direction.

[0073] According to a further embodiment, the terminal area of ​​a first contact element of at least one of the stacked power components or power submodules is in dry electrical contact with the terminal area of ​​the next power component or power submodule of the stacked power components or power submodules. The terminal area of ​​the next power component or power submodule of the stacked power components or power submodules is either the terminal area of ​​the third contact element or the terminal area of ​​the cooling element. Dry electrical contact means that the terminal areas are only pressed against each other and are not joined to each other. The terminal areas are therefore adjacent to each other in dry electrical contact.

[0074] According to a further embodiment, the power module comprises a pressure device for pressing the stacked power components or power sub-modules together to maintain a dry electrical contact. The greater the pressure, the higher the thermal conductivity between the terminal areas pressed together. The pressure device is, for example, electrically insulated from the power components or power sub-modules.

[0075] The pressure device may comprise, for example, a pin extending in the stacking direction through the sub-modules and their cooling elements. The pressure device may comprise a pressure element at each longitudinal end of the pin. The power component or power sub-module may be arranged between the pressure elements. At least one of the pressure elements may be connected to the pin by a screw thread, such that when the screw thread connection is tightened, the power component or power sub-module is sandwiched between the pressure elements and pressed against each other. One pressure element connected to the pin by the screw thread may be a nut. The other pressure element may be a leaf spring.

[0076] According to a further embodiment, a terminal area of ​​a first contact element of at least one of the stacked power components or submodules is bonded to a terminal area of ​​a next one of the stacked power components or submodules. For example, the terminal areas are directly bonded to one another, such as by soldering, welding, sintering or gluing. Thus, only a solder or sintered or welded or adhesive layer may be arranged between the terminal areas bonded to one another. For example, ultrasonic or laser welding may be used to bond the terminal areas.

[0077] According to a further embodiment, the stacked power components or power sub-modules are connected in a half-bridge configuration, for example the power components or power sub-modules stacked on top of each other belong to two different sides (high side or low side) of a half-bridge.

[0078] A half-bridge is, for example, an electrical circuit comprising two switch structures, the two switch structures being connected in series between two DC nodes, and an AC node being provided between the two switch structures. The DC node and the AC node may be electrically connected to terminals of a power module. Each switch structure may comprise one or more power components electrically connected in parallel.

[0079] The power module may be used in an electrical converter that can rectify a DC voltage that is supplied to, for example, a DC link or a battery, such as the battery of an electric vehicle. The inverter may also be capable of generating an AC voltage that is supplied to an electric motor, such as the motor of an electric vehicle. The power module may be used in automotive applications such as electric cars, motorcycles, buses, off-road construction vehicles, trucks, and charging stations. Applications in power grids where the power module is part of an electrical converter in an HVDC station that converts high voltage AC to high voltage DC and / or vice versa are also possible.

[0080] For example, a power module may comprise two or more power sub-modules, each of which comprises two or more power components connected in parallel, e.g., via first and / or second and / or third connection elements. The two or more power sub-modules may be stacked on top of each other and connected in series.

[0081] Next, a method for manufacturing a power submodule is defined. The method is suitable for manufacturing, for example, the power submodules described herein. Thus, all features disclosed in relation to the power submodule are also disclosed in relation to the method and vice versa.

[0082] According to one embodiment, the method includes providing an arrangement with a cooling element and at least two power components according to any of the embodiments described herein. The power components are arranged adjacent to each other on the cooling element and are electrically connected to the cooling element, with a terminal area of ​​a first contact element facing away from the cooling element. In a further step, an encapsulant is applied onto the cooling element and the power components are embedded in the encapsulant. In a further step, the first contact element and / or the encapsulant are partially peeled off, e.g. planarized, until the terminal area of ​​the first contact element facing away from the cooling element ends flush with the encapsulant and until the terminal area of ​​the first contact element is located at the same height relative to the cooling element or its top surface.

[0083] For example, the third contact element of the power component may be electrically connected to the cooling element. The third contact element may be bonded to the cooling element.

[0084] Next, a method for manufacturing a power module is defined, which method is suitable for manufacturing a power module, for example according to any of the embodiments described herein, and therefore all features disclosed in relation to a power module are also disclosed for a method for manufacturing a power module and vice versa.

[0085] According to one embodiment of a method for manufacturing a power module, the method includes providing at least two power components or power sub-modules according to any of the embodiments described herein and electrically connecting the power components or power sub-modules to each other.

[0086] According to a further embodiment, at least two power components or power submodules are electrically connected in series by stacking the power components or power submodules to be connected in series on top of each other and electrically connecting a first contact element of at least one of the stacked power components or power submodules to a third contact element or cooling element of the next power component or power submodule of the stacked power components or power submodules, the resulting configuration also being referred to herein as an assembly.

[0087] According to a further embodiment, at least two power components or two power sub-modules are electrically connecting the first contact element by a first connecting element; the second contact element is electrically connected by a second connecting element, and optionally Electrically connecting a third contact element of a power component or a cooling element of a submodule by a third connection element Thus, they are connected in parallel.

[0088] According to a further embodiment, the method comprises manufacturing several assemblies of series-connected power components or power sub-modules as described above. These assemblies are then connected in parallel.

[0089] In the following, the power component, the power sub-module, the power module, the method for manufacturing the power sub-module, and the method for manufacturing the power module will be described in more detail based on exemplary embodiments with reference to the drawings. The attached drawings are included to provide a further understanding. In the figures, elements of the same structure and / or function can be referred to by the same reference numbers. It should be understood that the embodiments shown in the figures are representations for illustration purposes and are not necessarily drawn to scale. Insofar as elements or components correspond to each other in terms of their functions in different figures, their description will not be repeated for each of the following figures. For clarity, some elements may not be indicated with corresponding reference numbers in all figures. [Brief description of the drawings]

[0090] [Figure 1] 1 illustrates various exemplary embodiments of a power component. [Diagram 2] 1 illustrates various exemplary embodiments of a power component. [Diagram 3] 1 illustrates various exemplary embodiments of a power component. [Figure 4] 1 illustrates various exemplary embodiments of a power component. [Diagram 5] 1 illustrates various exemplary embodiments of a power module. [Figure 6] 1 illustrates various exemplary embodiments of a power module. [Figure 7] 1 illustrates various exemplary embodiments of a power sub-module. [Figure 8] 1 illustrates various exemplary embodiments of a power sub-module. [Figure 9] 3 shows a further exemplary embodiment of a power module. [Figure 10] 3 shows a further exemplary embodiment of a power module. [Figure 11]3 shows a further exemplary embodiment of a power module. [Figure 12] 1 shows a flow chart of an exemplary embodiment of a method for manufacturing a power sub-module. [Figure 13] 1 shows a flow chart of an exemplary embodiment of a method for manufacturing a power module. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0091] FIG. 1 shows a first exemplary embodiment of a power component 100 in a cross-sectional view. The power component 100 comprises a power semiconductor device 1, a first contact element 3, a second contact element 4, and a third contact element 5. The power semiconductor device 1 is, for example, a transistor, such as an IGBT or a MOSFET, or a thyristor. The first contact element 3 and the second contact element 4 are electrically connected to a top side 10 of the power semiconductor device 1, and the third contact element 5 is electrically connected to a bottom side 12 of the power semiconductor device 1. For example, the first contact element 3 is electrically connected to an emitter or source electrode of the power semiconductor device 1, the second contact element 4 is electrically connected to a gate electrode of the power semiconductor device 1, and the third contact element 5 is electrically connected to a drain or collector electrode of the power semiconductor device 1.

[0092] The power semiconductor device 1, i.e. its semiconductor body, can be based on a wide bandgap material such as SiC or GaN or diamond.

[0093] The power semiconductor device 1 and the first and second contact elements 3 and 4 are surrounded and embedded in an electrical insulator 2. The insulator 2 is an encapsulation manufactured, for example, by transfer molding or injection molding. For example, the insulator 2 is made of resin. The contact elements 3, 4, 5 are electrically insulated from each other so that they can be at different potentials during operation. The first and second contact elements 3 and 4 are partially electrically insulated from each other via the insulator 2.

[0094] Each of the contact elements 3, 4, 5 comprises a respective terminal area 30, 40, 50 in the form of a terminal surface. In the pre-mounted configuration of the power component 100 shown in Figure 1, the terminal areas 30, 40, 50 are exposed and freely accessible from the outside for external electrical connection.

[0095] 1 , the terminal areas 30, 40 of the first contact element 3 and the second contact element 4 are arranged on the same side of the power semiconductor device 1 but at different heights relative to the top surface 10 of the power semiconductor device 1. The terminal area 50 of the third contact element 5 is arranged on a different side of the power semiconductor device 1 than the terminal areas 30, 40. Both the first contact element 3 and the second contact element 4 protrude from a top surface 20 of the electrical insulator 2 which extends essentially parallel to the top surface 10 of the power semiconductor device 1.

[0096] The electrical connection of several such power components 100 is simplified, since the terminal areas 30, 40 of the first contact element 3 and the second contact element 4 are arranged at different heights. Complicated disentanglement can be omitted.

[0097] 1 is a so-called chip-scale package, and the footprint of the entire component 100 is determined primarily by the footprint of the power semiconductor device 1, or its semiconductor body. For example, the footprint of the entire component 100 is at most 50% larger than the footprint of the power semiconductor device 1.

[0098] 2 shows the component 100 of FIG. 1 in a plan view of the upper surface 20 of the insulator 2. The area of ​​the terminal region 30 of the first contact element 3 is at least 50% of the area of ​​the upper surface 10 of the power semiconductor device 1.

[0099] 3 shows a further exemplary embodiment of a power component 100. Here too, the terminal areas 30, 40 are arranged at different heights relative to the top surface 10 of the power semiconductor device 1. In contrast to FIG. 1, however, the second contact element 4 is led out of the electrical insulator 2 at a side surface 21 of the insulator 2 and does not penetrate the top surface 20. Furthermore, the second contact element 4 comprises two parts. The first part extends from the top surface 10 towards the top surface 20. The second part extends laterally from the first part, through the side surface 21 and out of the insulator 1. The second part may be a lead frame.

[0100] Figure 4 shows a third exemplary embodiment of a power component 100. As in figure 1, a first contact element 3 and a second contact element 4 protrude from the electrical insulator 2 at a top surface 20 of the electrical insulator 2. Here, the top surface 20 comprises two parts arranged at different heights relative to the top surface 10 of the power semiconductor device 1. At a first part of the top surface 20 arranged at a higher position, the first contact element 3 protrudes from the top surface 20, and at a second part arranged at a lower height, the second contact element 4 protrudes from the top surface 20. Between the first and second parts of the top surface 20 a step is formed.

[0101] In the power component 100 shown in FIGS. 3 and 4, the creepage distance between the first contact element 3 and the second contact element 4 is increased compared to the power component 100 in FIG.

[0102] Figure 5 shows an exemplary embodiment of a power module 1000 in which two power components 100 according to Figure 1 are electrically connected to one another. With respect to the top side 10 of the power semiconductor device 1, the power semiconductor device 1 is arranged at the same height. The first contact elements 3 are electrically connected via first connection elements 300 and the second contact elements 4 are electrically connected via second connection elements 400. The first connection elements 300 are, for example, bus bars joined to the terminal areas 30. With respect to the top side 10 of the power semiconductor device 1, the first connection elements 300 and the second connection elements 400 are arranged at different heights.

[0103] Figure 6 shows, symmetrically to Figure 5, a second exemplary embodiment of a power module 1000 in which two power components 100 according to Figure 3 are electrically connected. In this case, a first connection element 300 is applied to the terminal areas 30 of the power components 100 in order to electrically connect them. The second terminal areas 40 are for example soldered to one another, whereby a second connection element 400 in the form of a solder connection is realised. The connection elements 300 and 400 are again at different heights with respect to the top side 10 of the power semiconductor device 1.

[0104] Fig. 7 shows a first exemplary embodiment of a power submodule 200. The power submodule 200 comprises the power component 100 according to Fig. 3 attached to an electrically conductive cooling element 6. The cooling element 6 is made of a metal, for example Cu. The cooling element 6 comprises a cooling structure 7 in the form of a cooling channel configured to guide a cooling liquid through the cooling element 6. The cooling channel 7 may be a microchannel. For example, the cooling channel 7 extends in a serpentine shape through the cooling element 6 (see also Fig. 11).

[0105] A terminal area 50 of the third contact element 5 is bonded to a top surface of the cooling element 6, and thereby electrically connected to the cooling element 6. For example, a solder or sintered or adhesive or welded layer 65 is formed between the third contact element 5 and the cooling element 6. The bottom surface of the cooling element 6 facing away from the power semiconductor device 1 constitutes a terminal area 60, which allows the power submodule 200 to be electrically connected. The cooling element 6 has a lateral extent greater than the power component 100.

[0106] Figure 8 shows a further exemplary embodiment of a power submodule 200. In contrast to what is shown in Figure 7, the power submodule 200 in Figure 8 comprises two power components 100 according to Figure 3. Both power components 100 are mounted laterally adjacent to one another on the same cooling element 6 and each is electrically connected to the cooling element 6 via a bonding layer 65. The cooling element 6 electrically connects the third contact elements 5 of both power components 100 to one another. The second contact elements 4 are also electrically connected to one another via a second connection element 400.

[0107] In Fig. 8 both power components 100 are embedded in a common encapsulation 25, for example a resin. The second connection element 400 is also embedded in the encapsulation 25 and protrudes from a side of the common encapsulation 25. The terminal area 30 of the first contact element 3 ends flush with the encapsulation 25.

[0108] The power submodule of FIG. 8 can be manufactured as follows (see also the flow chart of FIG. 12): In step S1_1, two power components 100 according to FIG. 3 are attached to the cooling element 6, for example bonded to the cooling element 6. Then, in step S1_2, the power components 100 are encapsulated in a common encapsulation 25. This can be done, for example, by transfer molding or injection molding. Thereafter, in step S1_3, a flattening is performed, in which the first contact elements 3 and / or the common encapsulation 25 are flattened until the terminal areas 30 of the first contact elements 3 end up flush with the encapsulation 25 and are located at the same height relative to the upper surface of the cooling element 6.

[0109] Since the encapsulant 25 is formed after the insulator 2 of the power component 100, an interface is formed between the encapsulant 25 and the insulator 2. This is true both when the encapsulant 25 is made of a different material than the insulator 2 or when it is made of the same material as the insulator 2.

[0110] FIG. 9 shows a further exemplary embodiment of a power module 1000 in which two power submodules 200 of FIG. 8 are stacked one on top of the other, with the first contact element 3 of the lower power submodule 200 being electrically connected to the cooling element 6 of the upper power submodule 200. A further cooling element 6 is arranged on the upper power submodule 200 and electrically connected to its first contact element 3. The cooling element 6 thereby electrically connects the first contact elements 3 to each other. In this way, a configuration is achieved in which the power submodules 200 are electrically connected in series and the power components 100 in each power submodule 200 are electrically connected in parallel. Each power submodule 200 constitutes one side of a half bridge. For example, the upper cooling element 6 can constitute a DC+ connection point, the lower cooling element 6 can constitute a DC- connection point, and the middle cooling element 6 constitutes an AC connection point.

[0111] In Fig. 9 the electrical connection between the first contact element 3 and the respective adjacent cooling element 6 is a dry electrical connection in which the contact element 3 adjoins and is pressed against the respective cooling element 6. For this purpose a pressure device 800 is used which presses the cooling element 6 against the adjacent first contact element 3. The higher the pressure, the better the thermal connection between the cooling element 6 and the first contact element 3. Thus, due to the pressure device 800, the large area of ​​the first contact element 3 and in particular the direct contact between the cooling element 6 and the first contact element 3 (without a spring contact element in between), the heat generated by the power semiconductor device 1 can be efficiently carried away.

[0112] 9 includes a leaf spring 802 connected to one longitudinal end of a pin 802 and a nut 803 connected to the other longitudinal end of the pin 802. The nut 803 threadably engages the pin 802. The pin 802 extends through the power sub-modules 200. Tightening the nut 802 presses the power sub-modules 200 together.

[0113] FIG. 10 shows a further exemplary embodiment of a power module 1000 with two power submodules 200 each with only one power component 100 attached to a cooling element 6 (see also FIG. 7). The power submodules 200 are electrically connected in series by being stacked on top of each other. Here too, the cooling element 6 is arranged on the upper power submodule 200, so that the first contact element 3 of this upper power submodule 200 is electrically and thermally connected to the cooling element 6. In contrast to FIG. 9, the cooling element 6 is not in dry contact with the adjacent first contact element 3, but is bonded to the adjacent first contact element 3, for example soldered or sintered or glued or welded. A corresponding bonding layer 65 is formed between the first contact element 3 and the respective adjacent cooling element 6 and is in direct contact with the first contact element 3 and the respective adjacent cooling element 6. Due to this bonding connection, a good thermal conductivity between the first contact element 3 and the adjacent cooling element 6 is achieved.

[0114] The power module 1000 of Fig. 10 already constitutes half bridges. To increase the power rating characteristics, several of these half bridges can be connected in parallel to form a larger power module 1000, as shown in Fig. 11.

[0115] In Fig. 11 a plan view is shown for the cross-sectional plane indicated by the dashed line in Fig. 10. The dashed line in Fig. 11 indicates the cross-sectional plane for the view of Fig. 10. As can be seen, three smaller power modules 1000 according to Fig. 10, also called an assembly, are connected in parallel to a larger power module 1000. Thereby, the cooling elements 6 of each plane are electrically connected to each other via a busbar 300 welded to the cooling elements 6. The second contact elements 4 of each plane are electrically connected to each other by a PCB 400 that is press-fitted into the respective second contact elements 4.

[0116] In Fig. 11 the cooling channels 7 of the cooling elements 6 can be seen. Each of the cooling channels 7 has a serpentine shape and extends laterally through a respective cooling element 6. Each cooling channel 7 starts at an inlet 70 of the cooling element 6 and ends at an outlet 71 of the cooling element 6. The cooling elements 6 are arranged to align the inlets 70 and outlets 71 of the different cooling elements 6 such that the inlets 70 and outlets 71 of the different cooling elements 6 are fluidly joined and one continuous cooling channel 7 extending through all three cooling elements 6 is realised.

[0117] A flow chart of an exemplary embodiment of a method for manufacturing the power module 1000 of FIG. 11 is shown in FIG. 13. In step S2_1, two power submodules 200 according to FIG. 7 are connected in series by stacking them on top of each other and electrically connecting the first contact element 3 of the lower power submodule 200 with the cooling element 6 of the upper power submodule 200, for example by soldering. This produces a compact power module 1000 in a half-bridge configuration, also referred to herein as an assembly (see, for example, FIG. 10). In step S2_1, several such assemblies, for example three, are produced. Then, in step S2_2, the assemblies are connected in parallel by connecting the cooling element 6 in each plane by a first connection element 300, for example a busbar 300, and connecting the second contact element 4 in each plane by a second connection element 400, i.e. a PCB 400.

[0118] The embodiments shown in Figures 1-13 as described above represent exemplary embodiments and therefore do not constitute a complete enumeration of all embodiments. Actual configurations may differ from the illustrated embodiments, for example, in terms of arrangement, devices, and elements. [Explanation of symbols]

[0119] sign 1. Power Semiconductor Devices 2. Electrical insulators 3 First Contact Element 4 Second Contact Element 5. Third Contact Element 6 Cooling Elements 7 Cooling structure / cooling channel 10 Top surface of power semiconductor device 1 12 Bottom surface of power semiconductor device 1 20 Upper surface of electrical insulator 2 21 Side of electrical insulator 2 25 Common Inclusion Bodies 30 terminal area of ​​first contact element 3 40 Terminal area of ​​second contact element 4 50 Terminal area of ​​third contact element 5 60 Terminal area of ​​cooling element 6 65 Bonding layer 70 Entrance 71 Exit 100 Power Components 200 Power Submodule 300 First connecting element 400 Second connecting element 800 Pressure Equipment 801 Leaf spring 802 pin 803 Nut 1000 Power Module S1_1~S2_2 Method steps

Claims

1. A power semiconductor device (1) having a top surface (10) and a bottom surface (12); an electrical insulator (2) surrounding the power semiconductor device (1); a first contact element (3) and a second contact element (4), both of which are in electrical contact with the power semiconductor device (1); A power component (100) comprising: each of the first contact element (3) and the second contact element (4) has a terminal area (30, 40) for electrically contacting the power component (100) with the outside via the contact element (3, 4); The power component (100) is configured to operate with the first contact element (3) and the second contact element (4) at different potentials; the terminal areas (30) of the first contact element (3) and the second contact element (4) are arranged on the same side of the power semiconductor device (1) but at different heights with respect to the top surface (10) of the power semiconductor device (1); The contact elements (3, 4) and the power semiconductor device (1) are embedded in the insulator (2); The power component (100) is a chip-scale package component, the footprint of the power component (100) being at most 50% larger than the footprint of the power semiconductor device (1).

2. At least one power component (100) according to claim 1; An electrically conductive cooling element (6) A power submodule (200) comprising: The power component (100) is disposed on the cooling element (6) and is electrically connected to the cooling element (6); The cooling element (6) comprises a cooling structure (7) for cooling the power semiconductor device (1); the cooling element (6) comprises a terminal area (60) facing away from the power semiconductor device (1), the terminal area (60) being configured to electrically contact the power submodule (200) with the outside via the cooling element (6); the terminal area (30) of the first contact element (3) faces away from the power semiconductor device (1) in a direction opposite to the terminal area (60) of the cooling element (6); The cooling structure (7) comprises a cooling channel (7) for directing a cooling fluid through the cooling element, the power sub-module (200).

3. At least two power components (100) according to claim 1, The at least two power components (100) are arranged on the cooling element (6), The power sub-module (200) of claim 2, wherein the at least two power components (100) are embedded in a common enclosure (25).

4. 2. The power component (100) according to claim 1, wherein the contact elements (3, 4) protrude from the electrical insulator (2) such that the terminal areas (30, 40) are located outside the insulator (2).

5. The first contact element (3) protrudes from a top surface (20) of the insulator (2); 5. The power component (100) according to claim 4, wherein the terminal area (30) of the first contact element (3) faces away from the power semiconductor device (1) and extends parallel to the top surface (20) of the insulator (2).

6. 6. A power component (100) according to claim 5, wherein an area of ​​the terminal region (30) of the first contact element (3) is at least 20% of an area of ​​the top surface (10) of the power semiconductor device (1).

7. The power component (100) of any one of claims 4 to 6, wherein the second contact element (4) protrudes from a side surface (21) of the insulator (2) or from the top surface (20) of the insulator (2).

8. the top surface (20) of the insulator (2) comprises a first portion and a second portion arranged at different heights relative to the top surface (10) of the power semiconductor device (1); 7. A power component (100) according to claim 5 or 6, wherein the terminal area (30) of the first contact element (3) is arranged in the area of ​​the first portion of the top surface (20) and the terminal area (40) of the second contact element (4) is arranged in the area of ​​the second portion of the top surface (20).

9. a third contact element (5) in electrical contact with the power semiconductor device (1); a terminal area (50) of the third contact element (5) for electrically contacting the power component (100) with the outside via the third contact element (5) is arranged on a different side of the power semiconductor device (1) and at a different height with respect to the top surface (10) of the power semiconductor device (1) compared to the terminal areas (30, 40) of the first contact element (3) and the second contact element (4); A power component (100) according to any one of claims 1 and 4 to 8, wherein the terminal area (50) of the third contact element (5) faces away from the power semiconductor device (1).

10. The power semiconductor device (1) is one of a MOSFET, a MISFET, an IGBT, a BIGT, and a thyristor; The first contact element (3) is connected to a source electrode or an emitter electrode of the power semiconductor device (1); the second contact element (4) is connected to a gate electrode of the power semiconductor device (1); 10. The power component (100) of claim 9, wherein the third contact element (5) is connected to a drain or collector electrode of the power semiconductor device (1).

11. A power component (100) according to any one of claims 1 and 4 to 10, The power components (100) are electrically connected to each other, forming a power module (1000).

12. a first connection element (300, 6) electrically connected to the first contact elements (3) of at least two power components (100); a second connection element (400) electrically connected to the second contact elements (4) of the at least two power components (100); Further equipped with With respect to the top surface (10) of the power semiconductor device (1) of the at least two power components (100), The power semiconductor devices (1) of the at least two power components (100) are arranged at the same height, 12. The power module (1000) of claim 11, wherein the first connection element (300) and the second connection element (400) are arranged at different heights.

13. At least two power components (100) according to claim 9 or 10 are stacked on top of each other, 13. The power module (1000) of claim 11 or 12, wherein the terminal area (30) of the first contact element (3) of at least one power component (100) of the stacked power components (100) faces and is electrically connected to the terminal area (50) of the third contact element (5) of a next power component (100) of the stacked power components (100).

14. At least two power submodules (200) according to claim 2 or 3 are stacked on top of each other, The power module (1000) according to any one of claims 11 to 13, wherein the terminal area (30) of a first contact element (3) of at least one of the stacked power submodules (200) faces and is electrically connected to the terminal area (60) of the cooling element (6) of a next power submodule (200) of the stacked power submodules (200).

Images