Method for producing a power electronic device, power electronic device and motor vehicle

Abstract

The invention relates to a method for producing a power electronic device (10), wherein a substrate, in particular a printed circuit board, is equipped with a power semiconductor (12) and a metallic region (14) of the substrate is electrically contacted by means of a metallic sleeve (18) for receiving a plug-in contact (20). Contacting comprises establishing a material-to-material connection between the sleeve (18) and the metallic region (14) of the substrate by means of an additive. The additive is first applied to the sleeve (18) before being brought into contact with the metallic region (14).

Description

[0001] The invention relates to a method for producing a power electronic device, a power electronic device produced according to the method and a motor vehicle with a power electronic device produced according to the method.

[0002] Methods for producing power electronic devices are known from the prior art, in which a substrate, for example a printed circuit board, is equipped with a power semiconductor and an area of ​​the substrate is electrically contacted by means of a metallic sleeve for receiving plug contacts. Compared to other methods known from practice, for example those in which plug contacts are designed as leadframes, contacting areas of the printed circuit board by means of a metallic sleeve for receiving a plug contact offers the advantage that the plug contact can be positioned at any location on the printed circuit board using this sleeve. This allows, for example, signal and control contacts close to the power semiconductor to be led away from the printed circuit board in a direction perpendicular to the printed circuit board and in particular out of the power electronic device.Leading out the contact is particularly advantageous when the power semiconductors and the sleeves are potted with a potting compound.

[0003] DE 11 2008 000 229 B4 discloses a power semiconductor device in which cylindrical connecting regions are arranged on a metallic circuit substrate and are connected to the circuit substrate essentially at right angles by a soldering material.

[0004] In practice, however, connecting the sleeves to the metallic areas of the substrate represents a challenge that should not be underestimated, particularly with regard to the spatial arrangement of the various components of the power electronic device on the substrate. For example, soldering processes often require a specific assembly sequence, so that fine wires, for example, which connect the metallic areas to electrical contacts of the semiconductors, can only be attached after the sleeves have been soldered to the substrate. Such wires, which are also referred to as bonding wires, are produced using specially designed tools, so-called bonding tools. The corresponding process is also known as wire bonding. The tools require a certain working space directly above the surface of the substrate, which is therefore not available for placing the sleeves.

[0005] The application of an additive to the areas of the substrate, for example the application of a solder paste, can also be difficult due to the limited space on the substrate. In particular, it may be that areas of the substrate are spatially difficult to access for the tools required for this purpose and are therefore not available for the application of a sleeve.

[0006] The invention is therefore based on the object of demonstrating a method for producing a power electronic device, a power electronic device and a motor vehicle with a power electronic device, which make the production of the power electronic device more flexible, in particular with regard to the possible spatial arrangement of the sleeves and / or the sequence of the process steps.

[0007] The object is achieved by a method for producing a power electronic device, a power electronic device, and a motor vehicle having a power electronic device having the features of the independent claims. The features of the dependent claims relate to advantageous embodiments.

[0008] The method for producing the power electronic device provides for a substrate to be populated with a power semiconductor. The substrate can be a printed circuit board. The substrate can be flat. In particular, the substrate is a substrate that has an insulating layer and metallic regions on the insulating layer. The metallic regions can form a wiring pattern. The substrate can be populated with a plurality of power semiconductors.

[0009] The power semiconductor can, in particular, be a power switch for an inverter, in particular a pulse-controlled inverter. The power semiconductor can comprise an insulated-gate bipolar transistor (IGBT) and / or a metal-oxide-semiconductor field-effect transistor (MOSFET).

[0010] The method provides for electrically contacting a metallic region of the substrate by means of the metallic sleeve for receiving a plug-in contact. The metallic sleeve is arranged, in particular, at an at least substantially right angle to the substrate. In this context, an arrangement at a right angle to the substrate is understood to mean, in particular, that the main extension direction of the sleeve, i.e., in particular, the direction along which a plug-in contact can be inserted into the sleeve, is oriented at right angles to the main extension directions of the substrate.

[0011] Contacting the metallic area by means of the sleeve involves creating a material bond between the sleeve and the metallic area of ​​the substrate by means of an additive.

[0012] This problem is solved in particular by first applying the additive to the sleeve before bringing the material bond into contact with the metallic area. It has been shown in practice that it is possible to first apply the additive to the sleeve. This makes it possible to place the sleeve, complete with the additive, on the substrate.

[0013] A manipulator used to place the sleeve on the substrate can, for example, engage the sleeve in the area of ​​the end facing away from the substrate, creating a gap between the manipulator and the substrate that is bridged by the sleeve. Any limitations of the working space directly above the substrate are thus less of a hindrance than if the additive had to be applied directly to the metallic area of ​​the substrate using a corresponding tool. In other words, the sleeve serves as a carrier for the additive during the assembly of the sleeve onto the substrate.

[0014] The method can provide for the additive to be applied to a contact surface of the sleeve facing the substrate after the material bond has been established. A contact surface of the sleeve oriented in this way allows a sufficiently large amount of additive to be applied to the sleeve and transported to the metallic area of ​​the substrate by means of the sleeve. The contact surface can, in particular, be circular. A circular contact surface can be realized in a practical manner on a sleeve for receiving a plug contact.

[0015] The sleeve can have a widened portion at its end facing the substrate after the material bond has been established. Such a widened portion enables secure connection and good contact, and can also form the contact surface. Such a widened portion can provide a comparatively large contact surface, which is advantageous with regard to the absorption of a sufficient amount of additive, particularly to ensure a reliable material bond.

[0016] The additive could, for example, be a sintering paste. Sintering pastes offer the advantage of process reliability, and they have also been shown to create bonded joints with a long service life. In this context, a silver sintering paste can be used, in particular. Silver sintering pastes have proven particularly suitable in terms of service life.

[0017] Alternatively and / or additionally, the additive can also be a solder and / or an adhesive. The solder can be applied to the sleeve, in particular, in the form of a solder paste.

[0018] The method can provide for the additive to be applied to the sleeve by means of a dispenser, a printing method and / or a dipping method. In this context, a dispenser is understood to mean, in particular, a dosing pump or a device for applying the additive which comprises a dosing pump. The printing method can in particular be a stencil printing method and / or screen printing. Such printing methods have proven to be particularly suitable for applying the materials considered as additives. The dipping method can in particular be a dipping method in which only the sleeve's contact surface is brought into contact with the surface of the additive. The implementation of such dipping methods is also referred to as "dipping".

[0019] The method may provide for the additive to be dried after the additive has been applied to the sleeve and before the additive is brought into contact with the metallic region. By drying the additive in this way, its consistency can be changed such that an additive which, in terms of its consistency, was previously well-suited for application to the sleeve, is, after drying, well-suited for being brought into contact with the metallic region, for creating a material bond with the metallic region, and / or for initially forming a durable coating on the sleeve for a certain period of time.The latter aspect can be particularly advantageous if the additive is not applied to the sleeve immediately before the sleeve is placed on the substrate, but rather the sleeve is placed on the substrate a certain time interval after the additive has been applied to the sleeve. This enables a temporal and thus also spatial separation of the process steps, which can in particular also include intermediate storage and / or transport of the sleeve between the application of the additive to the sleeve and the placement of the sleeve on the substrate.

[0020] The method may provide for the power semiconductors and the sleeves to be encapsulated with a potting compound. During the encapsulation process, the substrate may be accommodated in a suitable mold. Potting compounds of the type in question are also referred to as molding compounds. In particular, a space adjacent to the substrate is filled with the potting compound, creating a composite of substrate and potting compound that is bounded on one side by the substrate.

[0021] The sleeve may be a deep-drawn part. Sleeves of the type in question can be produced cost-effectively in large quantities using a deep-drawing process.

[0022] The power electronic device is manufactured by a method according to the present description.

[0023] The power electronic device can be designed such that the area of ​​the substrate electrically contacted by the sleeve is electrically connected to a control contact and / or a signal contact of the power semiconductor. Such control contacts or signal contacts are, in particular, not designed to transmit the electrical power supplied to the load supplied with electrical energy by the power electronic device. Therefore, much smaller conductor cross-sections are required for the electrical contacting of the control contacts or signal contacts of power semiconductors than for the transmission of the power provided by the power electronic device.The method is therefore particularly suitable for the electrical contacting of such control contacts and / or signal contacts of power semiconductors, since plug contacts with comparatively small cross sections can be advantageously realized by means of the described method.

[0024] The power electronic device can have a plurality of plug contacts, each of which is accommodated in a sleeve, wherein the described method for producing the electronic device has been applied accordingly to a plurality of sleeves during the production of the electronic device.

[0025] The power electronic device can be connected to an electronic component by means of the plug contact.

[0026] This component can, in particular, be a printed circuit board that extends in a plane parallel to the substrate. In this way, an electronic circuit for controlling the power semiconductors can be arranged spatially advantageously relative to the encapsulated power semiconductor in the manner of a layered structure. Furthermore, the orientation of the plug contact pointing at right angles away from the substrate proves to be particularly advantageous in this context. In particular, when the power electronic device has a plurality of plug contacts for contacting metallic regions of the substrate, this plurality of plug contacts, which are then aligned in particular parallel to one another, can be used to contact an electronic component arranged on the side of the encapsulation compound pointing away from the substrate.

[0027] The power electronic device may further comprise a liquid cooling system. This can be arranged, in particular, on the side of the substrate facing away from the encapsulating compound. Such an arrangement allows for efficient cooling of the power semiconductors.

[0028] The power electronics device can be a pulse-controlled inverter for operating an electric drive or a component of such a pulse-controlled inverter. The component of the pulse-controlled inverter is, in particular, a power module containing the power switches of the pulse-controlled inverter. In particular, a power electronics device designed as a power module can be connected to control electronics for controlling the power switches of the pulse-controlled inverter by means of the plug-in contact or the plurality of plug-in contacts. The control electronics can comprise a printed circuit board, via which the control electronics is electrically contacted by means of the plug-in contacts. The printed circuit board is arranged, in particular, parallel to the substrate.

[0029] The pulse-controlled inverter can comprise a plurality of power electronic devices of the type described. In particular, there can be three power electronic devices of the type described. This can be particularly advantageous for providing three-phase alternating current by means of the power electronic device.

[0030] The plurality of power electronic devices of the pulse-controlled inverter can be cooled by means of a common liquid cooling system. For this purpose, the power electronic devices of the pulse-controlled inverter can be arranged with their substrates, in particular, within a common plane. The individual power electronic devices of the pulse-controlled inverter can be connected, in particular, to the same component, in particular a printed circuit board, by means of the plug-in contacts. The printed circuit board can, in particular, extend parallel to the substrates of the individual power electronic devices and / or have control electronics for controlling the power semiconductors of the power electronic devices.

[0031] The motor vehicle has an electric drive and a power electronic device, or a power electronic device manufactured according to the described method. In particular, the motor vehicle can have a pulse-controlled inverter as described above with a plurality of power electronic devices. The power electronic device serves to supply the electric drive with electrical energy.

[0032] Power electronic devices of the type in question can be used particularly advantageously in a motor vehicle to supply its drive system with electrical energy. Due to the achievable compact design and simultaneous suitability for economical series production, the described power electronic devices and the described method for their production are predestined to meet the high requirements of the automotive sector in this regard.

[0033] Further practical embodiments of the invention are described below in conjunction with the drawings. They show: Fig. 1 a schematic representation of exemplary power electronic devices as part of a pulse inverter, Fig. 2 an enlarged view of one of the power electronic devices from Fig. 1, Fig. 3 a schematic representation of an exemplary metallic sleeve

[0034] The power electronic devices 10 shown as examples can be used as in the Fig. 1 and Fig. 2 examples can be components of a pulse inverter. In the case of the embodiment shown in the Fig. As shown in Figure 1, the cleaning inverter comprises three power electronic devices 10. The individual power electronic devices 10 comprise power semiconductors 12 arranged on a substrate. The substrate can be designed as a printed circuit board, as in the example shown, and can have metallic regions 14 arranged on an electrically insulating layer 16 of the substrate.

[0035] As in the Fig. 1 and Fig. 2, metallic areas of the substrate can be electrically contacted by means of metallic sleeves 18, wherein plug contacts 20 are accommodated in the metallic sleeves 18. As in the example shown in Fig. In the example shown in Figure 1, the plug contacts 20 can be designed as press-fit pins. In Fig. 2, the plug contacts 20 are not yet accommodated in the metallic sleeves 18.

[0036] The power semiconductors 12 and the sleeves 18 can be encapsulated with a potting compound. For illustrative reasons, the potting compound is not shown in the examples shown.

[0037] The metallic regions 14 of the substrate, which are electrically contacted by the metallic sleeves 18, can be connected to the power semiconductors 12 by wires 22, as in the example shown. Such contacting is particularly suitable when control inputs and / or signal inputs of the power semiconductors 12 are contacted by means of the plug contacts 20 accommodated in the sleeves 18.

[0038] As in the Fig. In the examples shown in Figure 1, the power electronic devices 10 can be contacted by means of additional electrical contacts 23. These can, in particular, have significantly larger cable cross-sections and accordingly serve to transmit the electrical power passed through the power semiconductors 12.

[0039] Furthermore, as in the examples shown, the power electronic devices 10 can be cooled by means of a liquid cooling system 24. The liquid cooling system 24 can, in particular, be arranged on the side of the substrate facing away from the power semiconductors 12 and the sleeves 18, as shown.

[0040] As in the examples shown, the sleeves 18 and thus the plug contacts 20 can extend away from the substrate at right angles to its plane of extension. A corresponding arrangement, as shown in the Fig. 1 and Fig. 2, allows contacting a printed circuit board arranged parallel to the substrate(s) by means of the plug contacts 20. This can in particular contain control electronics for controlling the power semiconductors 12, Fig. 1 and Fig. 2 is not shown for technical reasons.

[0041] The method for producing a power electronic device 10, in particular according to the Fig. 1 or Fig. 2, can provide that the additive is applied to a contact surface 28 of the sleeve 18 facing the substrate after the material connection has been made. The contact surface 18 can be as in the Fig. 3 example shown be circular.

[0042] The sleeve 18 can, as shown in the figures and in particular in Fig. 3, have a widened portion 26 at their end facing the substrate after the material connection has been established. The widened portion 26 can form the contact surface 28, as in the example shown.

[0043] The features of the invention disclosed in the present description, the drawings, and the claims may be essential, both individually and in any combination, for the realization of the invention in its various embodiments. The invention may be varied within the scope of the claims and taking into account the knowledge of the person skilled in the art. List of reference symbols 10 power electronic device 12 power semiconductors 14 metallic area 16 electrically insulating layer 18 sleeve 20 plug contacts 22 wire 23 electrical contacts 24 Liquid cooling 26 Widening 28 contact surfaces QUOTES CONTAINED IN THE DESCRIPTION

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

[0000] DE 11 2008 000 229 B4

[0003]

Claims

[1] Method for producing a power electronic device (10), wherein a substrate, in particular a printed circuit board, is equipped with a power semiconductor (12) and a metallic region (14) of the substrate is electrically contacted by means of a metallic sleeve (18) for receiving a plug contact (20), wherein the contacting comprises bringing about a material connection between the sleeve (18) and the metallic region (14) of the substrate by means of an additive, characterized by , that the additive is first applied to the sleeve (18) before bringing about the material connection, before it is brought into contact with the metallic area (14). [2] Method according to claim 1, characterized by that the additive is applied to a contact surface (28) of the sleeve (18) which, after the material connection to the substrate has been established, is in particular annular. [3] Method according to claim 1 or 2, characterized by that the sleeve (18) has a widened portion (26) at its end pointing towards the substrate after the material connection has been established, in particular wherein the contact surface (28) is formed by the widened portion. [4] Method according to one of the preceding claims, characterized by that the additive is a solder, in particular as a component of a solder paste, a sintering paste, in particular a silver sintering paste, and / or an adhesive. [5] Method according to one of the preceding claims, characterized by that the additive is applied to the sleeve (18) by means of a dispenser, a printing process, in particular by means of a stencil printing process and / or a screen printing process, and / or by a dipping process. [6] Method according to one of the preceding claims, characterized bythat the additive is dried after the additive has been applied to the sleeve (18) and before the additive is brought into contact with the metallic area (14). [7] Method according to one of the preceding claims, characterized by that the power semiconductor (12) and the sleeve (18) are potted with a potting compound. [8] Power electronic device (10) manufactured by a method according to one of the preceding claims, characterized by that the area of ​​the substrate electrically contacted by means of the sleeve (18) is electrically connected to a control contact (20) and / or a signal contact of the power semiconductor (12). [9] Power electronic device (10) according to claim 8 or manufactured according to one of claims 1 to 7, characterized bythat the power electronic device (10) is a pulse-controlled inverter for operating an electric drive or a component of such a pulse-controlled inverter. [10] Motor vehicle with an electric drive and a power electronic device (10) according to claim 8 or 9 or manufactured according to one of claims 1 to 7 for supplying the electric drive with electrical energy.

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