CN118302854A

CN118302854A - Electronic module

Info

Publication number: CN118302854A
Application number: CN202280078089.6A
Authority: CN
Inventors: S·瓦斯康塞洛斯·阿劳约; C·埃格尔; W·范埃姆登; M·洛伦兹
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2021-11-29
Filing date: 2022-11-28
Publication date: 2024-07-05
Also published as: DE102021213434A1; WO2023094663A1

Abstract

The invention relates to an electronic module comprising at least one circuit carrier provided at least on one side, on which a first electronic circuit of the electronic module is formed. The circuit carrier is at least partially thermally connected to the heat sink for dissipating heat from the electrical and/or electronic components of the first electronic circuit arranged on the circuit carrier. The heat sink has a housing which encloses a particularly closed cavity for a fluid, in particular a refrigerant. The housing is formed at least partially or completely from a semiconductor material, in particular a silicon-based semiconductor material, wherein at least one further electrical and/or electronic component of the electronic module and/or the second electronic circuit is formed in the semiconductor material.

Description

Electronic module

Technical Field

The present invention relates to an electronic module, an inverter comprising an electronic module and a heat sink, in particular comprised in the electronic module, according to the preamble of the independent claim.

Background

DE 10 2015 223 602 A1 by the applicant discloses a power module for an electric motor, which has at least one semiconductor switching half-bridge.

Disclosure of Invention

According to the invention, an electronic module of the above-mentioned type has a heat sink, in particular in the form of a heat-dissipating element, wherein the heat sink has a housing which encloses a cavity for a fluid, in particular a refrigerant. The housing is formed at least partially or completely from a semiconductor material, wherein the heat sink is connected, in particular in a material-locking manner, in a thermally conductive or thermally conductive manner, in particular via the housing, to at least one region of the circuit carrier which is provided at least on one side. The circuit carrier has, in particular, on at least one of its main sides, a first electronic circuit which comprises at least one electrical and/or electronic component. Preferably, the semiconductor material comprises silicon and/or germanium and/or silicon carbide or is formed from one or more of the semiconductors described above.

At least one further electrical and/or electronic structural element and/or a second electronic circuit of the electronic module is formed in the semiconductor material.

Advantageously, the electronic module has a high heat dissipation capacity by means of the described heat dissipation device. In this way, the higher power level electronics module can also be realized very simply and effectively. Furthermore, the semiconductor material of the heat sink serves at the same time as a carrier for the electrical and/or electronic components or the second electronic circuit. In this case, the electrical and/or electronic component and at least a part of the second electronic circuit can be formed at least partially or completely from a semiconductor material. In this case, known and established processes for functionally structuring and forming semiconductor functional structures made partially or completely of semiconductor material can advantageously be used. Therefore, the realization of the electronic module is also applicable in the range of mass production with a large number of pieces. The electronic module can be implemented in a particularly small and compact manner in the manner described, since the single or multiple circuit functions are advantageously located locally in the region of the heat sink. Due to the close proximity of the cooling fluid, the semiconductor material and thus the at least one further electrical and/or electronic structural element and/or the second electronic circuit may optimally be heat-dissipated.

In the case of a power electronic component as part of the first electronic circuit, there is therefore no temperature expansion that differs from one another, since the material between the power semiconductor structural element of the first circuit and the heat dissipating means, in particular as a heat sink or a heat spreading element, is identical or similar. Advantageously, the electronic module can thus be formed particularly permanently and durable.

The heat sink is preferably designed to absorb the heat loss at the location of the heat sink, in particular via the outer surface region of the housing, and to output the heat loss again at other locations spaced apart from this location.

The heat sink preferably has a thermal contact surface configured for a material-locking connection to a heat source, preferably a power semiconductor, and a heat output surface configured for a heat-conducting connection to a heat sink, in particular a heat sink.

The heat sink is preferably of planar design, wherein the thermal contact surface and the heat output surface extend parallel to one another. The heat sink can thus advantageously be constructed flat and space-saving and absorbs the heat loss of at least one power semiconductor or of a plurality of power semiconductors and distributes said heat loss laterally within the heat sink.

It is further preferred that the heat sink is designed for thermal diffusion, wherein the heat sink, in particular the heat diffusion element, is designed to absorb the lost heat at the location of the thermal contact surface and to spatially distribute the lost heat, preferably predominantly transversely, within the heat sink. Advantageously, hot spots, in particular local temperature increases, on electrical and/or electronic components, in particular power semiconductors, can thus be avoided.

In a preferred embodiment of the electronic module, the further electrical and/or electronic structural elements and/or the second electronic circuit within the heat sink are in electrical contact with the first electronic circuit on the circuit carrier. Functionally related electronic circuits are formed using electrical contacts. For the electrical contact, the circuit carrier and the heat sink have corresponding external connection contacts which are electrically connected to circuit parts on the circuit carrier or in the semiconductor material of the heat sink, respectively. In particular, such connection contacts are formed locally in the region of the thermal contact surface of the heat sink, and in particular also in the unarmed surface of the circuit carrier facing the thermal contact surface. The electrical connection of the corresponding external connection contacts is then effected, for example, together with the thermal connection of the circuit carrier and the heat sink, wherein the connection contacts are arranged one above the other and facing each other in a composite arrangement. In general, an advantageous possibility of separating electronic circuits that might otherwise be arranged on a circuit carrier is provided in this way. By locally repositioning the divided circuit parts as new carrier structures within the semiconductor material of the heat sink, the mounting surface of the circuit carrier can advantageously be reduced while maintaining the same electronic functionality. In addition to the compactness of the electronic module which can be achieved thereby, the electronic module can also be provided inexpensively.

In a preferred embodiment, the housing outer surface of the heat sink, in particular the above-mentioned thermal contact surface itself, is configured as a circuit carrier for the first electronic circuit. In this case, a conductor structure is applied on the outer surface, the conductor structure being formed, for example, from copper or copper alloy, silver or silver alloy, platinum or platinum alloy, gold or gold alloy and/or any other known electrically conductive material. Furthermore, electrical and/or electronic components are arranged on the outer surface of the housing and are electrically connected to the conductor structure in the case of the formation of the second electronic circuit. The electrical connection to the further electrical and/or electronic component and/or to the second electronic circuit is achieved in particular by way of a via as a conductive connection channel. In the case of silicon as semiconductor material, the connection channels are formed in the form of through-silicon vias.

A particular advantage arises in embodiments of the electronic module in which the heat sink comprises at least one capacitor, resistor, active structural element or sensor as part of a further electrical and/or electronic structural element and/or a second electronic circuit. For its formation within semiconductor materials, known techniques from semiconductor fabrication are known. Thus, advantageously, verified manufacturing criteria may be used.

In an advantageous embodiment of the electronic module, the electronic module is configured as a commutation unit for an inverter, wherein the first electronic circuit comprises at least one semiconductor switching half-bridge and the heat sink comprises an intermediate circuit capacitor of the commutation unit as part of the further electrical and/or electronic structural element or the second electronic circuit. In this case, a higher power can also be achieved by the commutation unit, since the circuit part arranged on the circuit carrier and the circuit part contained in the heat sink can be effectively dissipated.

The intermediate circuit capacitor is arranged and/or formed in the semiconductor material of the heat sink of the intermediate circuit capacitor. The intermediate circuit capacitor is preferably a semiconductor capacitor.

In a preferred embodiment, the intermediate circuit capacitor has a plurality or a large number of trench capacitors, in particular deep trench capacitors. The deep trench capacitor is preferably an STI capacitor (sti=shallow trench insulator). The intermediate circuit capacitor can thus advantageously be spatially integrated in the semiconductor material of the heat sink.

In a preferred embodiment, the capacitor has a plurality of electrodes, which each pass through a plurality of layers arranged one above the other. The capacitance of the capacitor is formed between the electrode and a layer adjacent to the electrode, at least one of the layers being arranged to overlap, the layer being penetrated by the electrode. Advantageously, the capacitor can therefore be constructed compactly and cheaply in the semiconductor material of the heat sink.

In a preferred embodiment, the intermediate circuit capacitor is formed in a recess in the housing of the heat sink. Advantageously, the intermediate circuit capacitor together with the heat sink can have a cuboid shape, in particular a cuboid shape. Advantageously, the intermediate circuit capacitor thus forms a volume fraction in the cuboid.

In a further preferred embodiment, the intermediate circuit capacitor may be a ceramic capacitor. Preferably, the ceramic capacitor forms a volume fraction in the heat sink.

In a preferred embodiment, the at least one sensor is constructed in the semiconductor material of the heat sink. The sensor can thus advantageously be integrated inexpensively in the semiconductor material and is therefore arranged close to and with a small heat transfer resistance at the heat generating component, in particular the semiconductor switch or the intermediate circuit capacitor.

In a preferred embodiment of the electronic module, the cavity formed in the heat sink is closed. Advantageously, the vapor chamber, heat pipe or thermosiphon may be formed by a heat sink.

In a preferred embodiment, the heat sink, in particular the housing, has a structure, in particular a microstructure, which is formed on the housing inner wall of the housing and faces the opening of the cavity and is designed to hold the fluid in the structure and/or to guide the fluid in the structure and/or to move the fluid. The structure is formed, for example, by an open-cell foam and/or a tube. Advantageously, the heat sink can therefore be operated widely or completely independently of the position.

In a preferred embodiment, the open cell structure is a capillary structure. Advantageously, the capillary structure, in particular the wick structure or the tubule structure, may guide the fluid from the heat source to the heat sink within the cavity by capillary forces.

The heat sink preferably has a heat-absorbing surface and a heat-outputting surface which is especially configured parallel thereto. The heat dissipating device is configured for evaporating a fluid at the heat absorbing surface and condensing at the heat output surface, in particular a heat sink. It is further preferred that the heat sink is configured for guiding condensed fluid back to the heat absorbing surface through the open-celled structure. Thus, advantageously, a closed evaporation-condensation circuit can be formed in the heat sink. Advantageously, the heat sink can therefore spread the heat formed at the heat source, in particular the lost heat generated in the semiconductor material itself, and/or direct it transversely to the planar extension of the heat sink to the fluid in the cavity.

In a preferred embodiment, the fluid comprises a refrigerant. The refrigerant is preferably configured for boiling and recondensing. Advantageously, therefore, the refrigerant can absorb the lost heat upon boiling and, in turn, output the lost heat upon recondensing to a liquid state. Advantageously, heat conduction or diffusion can thus be established in the cavity of the heat sink by the evaporation enthalpy and the movement of the refrigerant in the cavity of the heat sink.

Preferably, the refrigerant has one or more of propane and/or butane, ammonia, water, methanol, ethanol or carbon dioxide. Advantageously, therefore, the refrigerant may be formed ozone-friendly. In a further embodiment, the refrigerant has at least one halogenated, preferably chlorinated and/or fluorinated alkane or alkene, in particular a hydrofluoroalkene, which is also referred to as a hydrofluoroalkene.

In further embodiments, the refrigerant is formed from water or an alcohol. Therefore, advantageously, the refrigerant can be provided inexpensively.

In a preferred embodiment of the electronic module, the housing is in heat-conducting connection with a heat sink which is designed in particular for guiding a fluid. The heat sink is, for example, an aluminum heat sink, which is designed for connection into a fluid circuit, in particular into a cooling circuit of a vehicle, in particular an electric vehicle. Advantageously, the electronic module can therefore be cooled inexpensively and has a particularly low heat transfer resistance from the circuit carrier to the aluminothermic fluid. It is thus further advantageous that a particularly effective heat transfer and good heat diffusion and heat distribution can be achieved between the circuit part itself to be heat-dissipated and the fluid-conducting heat sink, in particular cooling water, by means of the heat-dissipating device which is itself formed from semiconductor material.

The invention also relates to a heat sink, in particular of the type described above. The heat sink, in particular the heat diffusion element, has a housing formed from or having at least one semiconductor material, which encloses a cavity. The cavity is at least partially filled with a refrigerant. The housing preferably has an open-pore structure, in particular a capillary structure and/or a microchannel, or a tubule structure which is formed on a housing wall of the housing and is arranged in the cavity or is directed towards the cavity. At least one electrical and/or electronic component and/or electronic circuit is formed in the semiconductor material.

In a preferred embodiment of the heat sink, the electrical and/or electronic components and/or the electronic circuit are arranged outside the cavity. Thus, there is no risk of electrical contact with the cooling fluid. To ensure potential separation, the semiconductor material may further comprise an insulating layer, which prevents an electrical connection between the electrical and/or electronic structural element and/or the electronic circuit and the cooling fluid.

In a preferred embodiment of the heat sink, the heat sink has electrical external connection contacts, in particular on the outer surface of the housing, which are electrically connected to the electrical and/or electronic component and/or the electronic circuit and are designed such that the electrical and/or electronic component and/or the electronic circuit is electrically connected to a further circuit of the circuit carrier, which can be thermally connected to the heat sink for heat dissipation.

The invention also relates to an inverter having at least one electronic module of the above-described type, in particular in the form of a commutation unit. The inverter has at least one commutation cell for each phase of the inverter.

Further preferably, the inverter has a drive for at least one semiconductor switching half-bridge of the commutation cell.

The invention also relates to an electric vehicle with an inverter of the above-mentioned type and an electric drive machine. The drive machine has at least three phases, five phases or six phases, or a multiple of three phases, and has at least one stator coil for each phase. The inverter is configured to supply power to stator coils of the motor, in particular, the stator, to generate a rotating magnetic field.

Drawings

The invention will now be described hereinafter with the aid of the drawings and further embodiments. Further advantageous embodiments result from the combination of features described in the dependent claims and the figures.

Fig. 1 shows an exemplary embodiment of an electronic module as a commutation unit or inverter, having a refrigerant-filled heat sink, in particular a heat diffusion element, which is designed to absorb lost heat from a semiconductor switching half-bridge connected to the heat sink and to output the lost heat to a fluid-conducting heat sink, wherein the heat sink is formed from or comprises a semiconductor material of this kind and has a semiconductor capacitor, in particular a deep trench capacitor, which is embodied in the semiconductor material.

Detailed Description

Fig. 1 shows an embodiment of an electronic module as a commutation unit or more advanced as an inverter 1. The inverter 1 has a heat sink 2, in particular a heat diffusion element. In this embodiment, the heat sink 2 is formed of a semiconductor material, in particular silicon. The heat sink 2 has a cavity 5 surrounded by two housings 3 and 4 forming the heat sink 2. On the shells 3 and 4, respectively, microstructures, in particular tubule structures or capillary structures, are formed, which are designed to transport the refrigerant 7 accommodated in the cavity 5 and/or to evaporate said refrigerant by surface enlargement, in this embodiment, the shells are each designed as half shells and are connected to one another, for example by welding or bonding, in particular friction welding or ultrasonic welding.

The capillary structure 6 is produced, for example, by means of trench etching or by means of a laser.

The inverter 1 further comprises a heat sink 8, which in this embodiment is formed as a ceramic-structured heat sink. Heat sinks made of copper or copper alloys or aluminum alloys are also conceivable. The heat sink 8 encloses a cavity 10 into which the heat sink extends. The heat sink 11 is exemplarily shown. In addition or independently of the heat sink, the webs can be formed on the heat sink 8. The cooling ribs and/or webs, which are formed in the cavity 10, are each designed to conduct the heat loss surface to a fluid flowing in the cavity 10, for example cooling water, in an increased manner.

In this example, the heat sink 2 is connected to the heat sink 8 by means of a layer 9 (in this embodiment a composite layer), in particular of electrically insulating and/or thermally conductive construction. The heat-conducting layer 9 is formed, for example, from a DCB substrate (dcb=direct copper bonding) or an AMB substrate (amb=active metal brazing), and can thus be soldered or sintered to the heat spreader 2 and the heat sink 8 in this embodiment. The heat sink 8, which is designed to guide a fluid, in particular cooling water, can thus be electrically separated from the heat sink 2, in particular a heat diffusion element.

In this exemplary embodiment, the heat sink 2 is constructed flat and forms, for example, via the half-shell 3, a circuit carrier or substrate for a part of the electronic circuit, i.e. in this exemplary embodiment the commutation unit of the inverter 1.

Furthermore, the intermediate circuit capacitor 12 is formed in particular in the semiconductor material of the heat sink 2 and in particular in the half-shell 3, which in this embodiment also forms the circuit carrier for the electronic circuit described above. The intermediate circuit capacitor 12 is built in the semiconductor material of the heat sink 2, for example as a deep trench capacitor. The deep trench capacitor comprises a plurality of deep trench structures, in particular etched or laser-generated, which are each configured for forming a capacitance with respect to the semiconductor material surrounding the deep trench structures.

In this exemplary embodiment, the conductive layers are connected, in particular in a material-locking manner, to the heat sink 2, in particular to the half-shell 3 forming the circuit carrier, which conductive layers each form a rewiring structure for the electronic circuit, i.e. the semiconductor switching half-bridge of the inverter 1 and the further electronic components in this exemplary embodiment.

The inverter 1 comprises a semiconductor switching half-bridge comprising a high-side transistor 17 and a low-side transistor 18. The high-side transistor 17 is connected to the conductive layer 13 by means of a solder or sintering agent 22. The low-side transistor 18 is connected to the conductive layer 15 by means of a solder 22. The conductive layers 13 and 15 are welded or sintered to the heat sink 2, in particular the housing shell 3. The conductive layer forms a rewiring structure that may be an integral part of the heat sink 2. In this way, an indirect, material-locking connection is formed between the semiconductor switch and the heat sink 2.

The inverter 1 further comprises a driver 19, in particular a gate driver for a semiconductor switching half-bridge, which driver comprises semiconductor switches 17 and 18. The driver 19 is connected to the half-shell 3 of the heat sink 2 by means of the conductive layer 16. A bonding wire 24 connecting the driver 19 with the gate terminal of the low-side semiconductor switch 18 is schematically shown.

The inverter 1, in particular the commutation cell of the inverter 1, further has a current sensor 20 which is designed to detect the output current of the semiconductor switching half-bridge and to generate a current signal representing the detected current and to transmit the current signal to the drive 19. The current sensor 20 is formed, for example, by a shunt resistor or a magnetic field sensor, which is designed to detect the phase current of the commutation cell flowing in the busbar 14. The busbar 14 is connected to the heat sink 2, for example by welding or sintering.

In this embodiment, the inverter 1 further comprises a temperature sensor 21 constructed and arranged to detect the temperature of the semiconductor switching half-bridge. In this embodiment, the temperature sensor 21 is connected to the conductive layer 13 by means of a solder 22 in a material-locking manner. For example, the temperature sensor 21 is formed by an NTC resistor (ntc=negative temperature coefficient).

In addition or independently of the temperature sensor 21, the inverter 1 may have a temperature sensor 23 embodied in the heat sink 2, in particular in the semiconductor material of the heat sink 2. The temperature sensor 23 is produced in the semiconductor material of the heat sink 2, for example by means of cathodic atomization (also referred to as sputtering) or CVD (cvd=chemical vapor deposition). The temperature sensor 22 is therefore designed to detect the temperature in the vicinity of the semiconductor switching half-bridge, in particular the transistors 17 and 18.

The intermediate circuit capacitor 12 can be embodied in the semiconductor material of the heat sink 2 in a space-saving and inexpensive manner and is thus a component of the heat sink 2. The temperature sensor 23 may be an integral part of the heat sink 2.

The transistors of the semiconductor switching half-bridge are configured, for example, as field effect transistors, IGBTs (igbt=insulated gate bipolar transistor) or HEMT transistors (hemt=high electron mobility transistor) or silicon carbide transistors.

The driver 19 is, for example, a CMOS driver, in particular an ASIC (asic=application specific integrated circuit), SIP (sip=system in package), microcontroller or microprocessor. The driver 19 is structured on, for example, an SOI substrate (soi=silicon on insulator).

The semiconductor switches 17 and 18 are, for example, embodied as shell-less semiconductor switches, in particular as bare chips.

In addition to embodiments in the form of a commutation unit or inverter 1, the electronic module can also comprise further electronic functions and/or further circuit components. The division of the functional circuit into a circuit part arranged on the outer surface of the housing of the heat sink 2, in particular on the thermal contact surface, and a circuit part arranged and/or constructed in the semiconductor material of the heat sink can thus be realized quite differently depending on the application. Instead of the housing outer surface of the heat sink 2 as a carrier structure, a separate circuit carrier can alternatively be provided in the electronic module, which circuit carrier is thermally connected to the housing outer surface of the heat sink and is also electrically connected to the circuit parts in the semiconductor material of the heat sink 2.

Claims

1. Electronic module comprising at least one circuit carrier equipped at least on one side, on which a first electronic circuit of the electronic module is formed, wherein the circuit carrier is at least partially thermally connected to a heat sink for dissipating electrical and/or electronic components of the first electronic circuit arranged on the circuit carrier, and wherein the heat sink has a housing (3, 4) which encloses a cavity (5), in particular a closed cavity, for a fluid (7), in particular a refrigerant, characterized in that the housing (3, 4) is formed at least partially or completely from a semiconductor material, in particular a silicon-based semiconductor material, wherein at least one further electrical and/or electronic component (12) of the electronic module and/or a second electronic circuit is formed in the semiconductor material.

2. Electronic module according to claim 1, characterized in that the further electrical and/or electronic structural element and/or the second electronic circuit within the heat sink is in electrical contact with the first electronic circuit on the circuit carrier in the case of forming a functionally relevant electronic circuit.

3. Electronic module according to claim 1 or 2, characterized in that a housing outer surface, in particular a thermal contact surface, of the heat sink is configured as the circuit carrier of the first electronic circuit, and that an electrical conductor structure is applied on the housing outer surface and at least one electrical and/or electronic structural element is arranged, which is electrically connected to the conductor structure in the formation of the first electronic circuit.

4. Electronic module according to any of the preceding claims, characterized in that the heat dissipation means comprises at least one capacitor, resistor, active structural element or sensor as part of the further electrical and/or electronic structural element and/or the second electronic circuit.

5. Electronic module according to any of the preceding claims, characterized in that the electronic module is configured as a commutation unit for an inverter, wherein the first electronic circuit comprises at least one semiconductor switching half-bridge and the heat dissipation means comprises an intermediate circuit capacitor of the commutation unit as part of the further electrical and/or electronic structural element or the second electronic circuit.

6. The electronic module according to claim 5, characterized in that the intermediate circuit capacitor (12) is configured as a semiconductor capacitor, in particular as a plurality or a large number of trench capacitors, such as deep trench capacitors.

7. The electronic module according to claim 5 or 6, characterized in that the intermediate circuit capacitor (12) has a plurality of electrodes passing through a plurality of layers arranged one above the other, wherein the capacitance of the intermediate circuit capacitor (12) is formed between the electrode and at least one of the layers arranged one above the other and the layer adjacent to the electrode.

8. Electronic module according to any of the preceding claims, characterized in that the heat dissipating device (2) has a structure (6) facing the opening of the cavity (5), which structure is configured for holding the fluid in the structure (6) and/or transporting the fluid in a guided manner.

9. Electronic module according to claim 8, characterized in that the open-pore structure (6) is a capillary structure.

10. The electronic module according to any of the preceding claims, characterized in that the refrigerant (7) is configured for boiling by absorbing lost heat and for outputting the lost heat by recondensing.

11. The electronic module according to any of the preceding claims, characterized in that the housing (3, 4) is in heat-conducting connection with a heat sink (8), in particular a heat sink configured for guiding a fluid.

12. Inverter (1) having at least one electronic module according to any one of claims 4 to 11, in particular as a commutation unit (2, 12, 17, 18), wherein the inverter (1) has at least one commutation unit (2, 12, 17, 18) for each phase.

13. Heat dissipation device, in particular for a commutation unit according to any one of claims 4 to 11, wherein the heat dissipation device (2) has a housing (3, 4) formed of or with at least one semiconductor material, in particular silicon-based semiconductor material, which encloses a cavity (5), wherein the cavity (5) is at least partially filled with a refrigerant (7), wherein the housing has an open-pore structure (6), in particular a capillary structure and/or a microchannel, or a tubule structure which is formed on a housing wall of the housing (3, 4) and is arranged in the cavity (5), and wherein at least one electrical and/or electronic component and/or electronic circuit is formed in the semiconductor material.

14. Heat sink according to claim 13, characterized in that the electrical and/or electronic structural element and/or the electronic circuit is arranged outside the cavity.

15. The heat sink according to claim 13 or 14, characterized in that the heat sink has electrical external connection contacts, in particular on an outer surface of the housing, which are electrically connected to the electrical and/or electronic component and/or the electronic circuit and are configured such that the electrical component and/or the electronic circuit is electrically connected to a further circuit of the circuit carrier, which is thermally connectable to the heat sink for heat dissipation.