METHOD FOR FORMING A POWER MODULE

Abstract

A method of forming a power module (20), the method comprising the following steps: Providing a carrier (22); Arranging an electrically conductive first plate (24) on the carrier (22); Arranging an electrically conductive second plate (26) next to the first plate (24) on the carrier (22), wherein the first plate (24) has a first thickness (H1) and the second plate (26) has a second thickness (H2) and wherein the first thickness (H1) is greater than the second thickness (H2); Arranging a vacuum film (70) over the carrier (22), the first plate (24) and the second plate (26) such that a cavity (78) is formed at least between the plates (24, 26) and the vacuum film (70), wherein a gas outlet (72) for evacuating the cavity (78) extends through the vacuum film (70), and that the cavity (78) is sealed gas-tight with the exception of the gas outlet (72); Arranging the carrier (22) and the plates (24, 26) with the vacuum film (70) in a chamber (82) of an autoclave (80); Evacuating the cavity (78) between the plates (24, 26) and the vacuum film (70); Pressurizing the chamber (82) with gas having a temperature sufficient to fix the plates (24, 26) to the carrier (22); Releasing the gas from the chamber (82); Removing the carrier (22) and the plates (24, 26) with the vacuum film (70) from the chamber (82); Removing the vacuum film (70) from the carrier (22) and the plates (24, 26); Arranging at least one semiconductor switch (60, 62) on the first plate (24); and electrically coupling the semiconductor switch (60, 62) to the second plate (26).

Description

[0001] The invention relates to a method for forming a power module, in particular a power module produced by the method.

[0002] A conventional power module may include a carrier, one or more electrically conductive sections on the carrier, and one or more semiconductor switches mounted on the sections. The carrier may include or consist of one or more layers of pre-impregnated fibers ("prepreg"). The semiconductor switches may be controlled by one or more electronic components of the power module. The semiconductor switches may be configured as high-speed and / or high-power switching devices.

[0003] In a conventional method for forming a power module, a plate is placed on the substrate, and the plate is pressed against the substrate by a press, so that the plate is fixed to the substrate after the appropriate pressure is applied. After this fixing step, the plate is etched, so that the plate is separated into sections on which the semiconductor switches and electronic components are arranged, wherein the sections are electrically insulated from one another and wherein the sections are arranged next to one another at a given distance.

[0004] With regard to semiconductor switches, it is advantageous to have a thick section as a support for the corresponding semiconductor switch. The thick section for supporting the semiconductor switch can be referred to as a power pattern. The thick section can contribute to good heat dissipation from the corresponding semiconductor switch. Furthermore, the thick section can contribute to a low inductance of the semiconductor module. The low inductance of the semiconductor module can lead to a high power performance of the semiconductor module. To provide the thick section, a correspondingly thick plate must be coupled to the carrier in the pressing step.However, the thick section has a correspondingly large weight and requires a correspondingly large amount of space. Other parts of the power pattern, which can be referred to as the signal pattern, generate less heat than the power pattern, and a thin plate may be sufficient for the signal pattern. However, providing plates of different thicknesses for the line pattern and the signal pattern will cause problems when arranging the plates in the press due to the different thicknesses.

[0005] US 2009 / 0 129 038 A1 describes a circuit device incorporating a power element that generates a large amount of heat. The circuit device comprises: a circuit board whose surface is covered with an insulating layer; a conductive pattern formed on the surface of the insulating layer; a circuit element electrically connected to the conductive pattern; and a lead connected to a pad formed from the conductive pattern. Furthermore, a power supply element is attached to the upper surface of a land portion formed of a part of the lead. Accordingly, the land portion serves as a heat sink, thus contributing to heat dissipation.

[0006] US 6 291 880 B1 describes a semiconductor device having a main circuit part with a semiconductor device formed on an electrode plate of a lead frame and a control circuit part with protection functions formed into an integral molded structure by a resin molding.

[0007] US 2017 / 0 358 516 A1 describes a power module comprising a first substrate, a first metal layer with a thickness between 5 µm and 50 µm, at least one conductive structure with a thickness of at least 100 µm, and at least one power component. The power component is arranged on the first substrate, the first metal layer, or the conductive structure. A drive electrode of the power component is electrically coupled to the first metal layer, while at least one power electrode of the power component is electrically connected to the conductive structure. Structuring of the first metal layer is possible through isotropic etching.

[0008] US 2015 / 0 319 857 A1 describes an epoxy resin composition comprising an epoxy compound, a curing agent and an inorganic filler, wherein the inorganic filler comprises aluminum oxide and aluminum nitride.

[0009] Therefore, it is an object of the present invention to provide a method of forming a power module comprising at least one semiconductor switch that is simple and inexpensive, that contributes to proper heat dissipation from the semiconductor switch during operation of the power module, that contributes to the power module being lightweight, and / or that contributes to the power module not requiring much space.

[0010] The object is solved by the subject matter of the independent claim. Advantageous embodiments are specified in the dependent claims.

[0011] One aspect relates to a method for forming a power module, the method comprising the following steps: providing a carrier; arranging an electrically conductive first plate on the carrier; arranging an electrically conductive second plate next to the first plate on the carrier, wherein the first plate has a first thickness and the second plate has a second thickness, and wherein the first thickness is greater than the second thickness; arranging a bagging film over the carrier, the first plate, and the second plate such that a cavity is formed at least between the plates and the bagging film, wherein a gas outlet for evacuating the cavity extends through the bagging film, and that the cavity is sealed gas-tight with the exception of the gas outlet; arranging the carrier and the plates with the bagging film in a chamber of an autoclave; evacuating the cavity between the plates and the bagging film;Pressurizing the chamber with gas having a temperature sufficient to fix the plates to the carrier; releasing the gas from the chamber; removing the carrier and the plates with the vacuum film from the chamber; removing the vacuum film from the carrier and the plates; arranging at least one semiconductor switch on the first plate and electrically coupling the semiconductor switch to the second plate.

[0012] The thick first plate can help ensure that heat is properly dissipated from the semiconductor switch during operation of the power module. The thin second plate can help ensure that the power module is lightweight and compact. The vacuum film allows for easy fixing of plates of different thicknesses to the carrier because the pressure is evenly distributed by the vacuum film. In particular, due to the evacuated cavity and the pressurized chamber, the vacuum film provides uniform pressure to the surrounding components, i.e., the plates. Due to the high temperature in the chamber and due to the pressure, the plates are properly fixed to the carrier. Furthermore, the process can be carried out in a simple and cost-effective manner.

[0013] The semiconductor switch can be electrically coupled to the second plate by one or more wire bonds. The semiconductor switch arranged on the thick first plate, i.e., a power pattern, can be used for currents greater than the currents for which the thin second plate, i.e., a signal pattern, is used. This contributes to very good heat dissipation from the semiconductor switch, especially when it is a high-power semiconductor chip. For example, the semiconductor switch can be configured to handle currents of more than 10 A, and the signal pattern can be configured to handle currents of less than or equal to 10 A. In addition to the semiconductor switch, one or more further semiconductor switches can be arranged on the first plate.Alternatively or additionally, one or more electronic components for controlling the semiconductor switch(es) may be arranged on the signal pattern and may be electrically coupled to the one or more semiconductor switches.

[0014] The gas outlet is coupled to the vacuum film in a gas-tight manner. The gas outlet can be coupled to the vacuum film before or after the vacuum film is arranged over the carrier and the plates. The gas outlet can be configured to communicate with the cavity and with a vacuum pump. The gas outlet can extend from the cavity to the vacuum pump. After evacuating the cavity and before pressurizing the chamber, the gas outlet can be closed and disconnected from the vacuum pump. Alternatively, the gas outlet can be coupled to the vacuum pump until the carrier and the plates with the vacuum film are removed from the chamber.

[0015] According to one embodiment, the method comprises, prior to arranging the plates on the carrier, separating the first plate into a first portion and a second portion such that the first portion is electrically insulated from and spaced apart from the second portion; wherein the semiconductor switch is arranged on the second portion and is electrically coupled to the first portion. Optionally, one or more further semiconductor switches may be arranged on the second portion.

[0016] According to one embodiment, the method comprises, prior to arranging the plates on the carrier, separating the second plate into a third section and a fourth section such that the third section is electrically insulated from and spaced apart from the fourth section. If the one or more electronic components for controlling the semiconductor switch(es) are to be arranged on the signal pattern, these electronic components can be arranged on the third section, and the semiconductor switch(es) can be electrically coupled to the electronic component(s) on the third section.

[0017] According to one embodiment, the first and / or second plate are separated into the corresponding sections by sawing. This may allow the omission of an etching step for separating the plates into the corresponding sections.

[0018] According to one embodiment, the vacuum foil is arranged such that it is gas-tightly coupled to a bottom side of the carrier, wherein the bottom side of the carrier faces away from the semiconductor chip. This can help to provide a suitable pressure between the plates and the carrier. The vacuum foil can be gas-tightly coupled to the bottom side of the carrier such that at least a portion of the bottom side is free of the vacuum foil. Alternatively, the vacuum foil can be gas-tightly coupled to a lateral side surface of the carrier. Alternatively, the vacuum foil can completely enclose the carrier and the plates. Alternatively, the carrier with the plates can be arranged on a heat sink, and the vacuum foil can be arranged such that it encloses the carrier, the plates, and at least partially the heat sink.

[0019] According to one embodiment, the vacuum film is coupled gas-tight to the underside of the carrier by a vacuum sealant. This contributes to the gas-tight arrangement of the vacuum film. When the carrier is arranged on the heat sink, the vacuum film can be coupled gas-tight to the underside of the heat sink by the vacuum sealant.

[0020] According to one embodiment, the gas temperature in the chamber is between 50°C and 200°C, e.g., between 80°C and 150°C, e.g., at 120°C. Alternatively or additionally, the overpressure in the pressurized chamber is between 10 kPa and 100 kPa, e.g., between 30 kPa and 60 kPa above atmospheric pressure. Alternatively or additionally, the negative pressure in the evacuated space is between 10 -3 hPa and 10 -8 hPa, e.g. between 10 -4 hPa and 10 -6 hPa.

[0021] According to one embodiment, the semiconductor switch is electrically coupled to the first and / or third section, or optionally to the electronic component on the third section, by at least one wire bond. This can contribute to the ease of coupling the semiconductor switch to the first and / or third section.

[0022] According to one embodiment, the first plate has a thickness between 100 µm and 1 cm; and / or the second plate has a thickness between 1 µm and 1 mm. For example, the first plate has a thickness between 500 µm and 5 mm, and / or the second plate has a thickness between 35 µm and 500 µm.

[0023] According to one embodiment, the first and / or second plate comprises or is / are made of copper.

[0024] According to one embodiment, the carrier comprises or consists of one or more layers of pre-impregnated fibers.

[0025] According to one embodiment, the method comprises: disposing an electrically conductive signal pin on the fourth portion, wherein the signal pin is configured to electrically couple the power module to an external device. The external device may be configured to communicate with the electronic component and / or the semiconductor switch(es).

[0026] The power module comprises: the carrier; the electrically conductive first section and the electrically conductive second section on the carrier, wherein the first section is electrically insulated from and spaced apart from the second section, and wherein the first section and the second section each have the first thickness; the electrically conductive third section and the electrically conductive fourth section on the carrier, wherein the third section is spaced apart from the fourth section, wherein the third section and the fourth section are electrically insulated from and spaced apart from the first section and the second section, wherein the third section and the fourth section each have the second thickness, and wherein the first thickness is greater than the second thickness; the at least one semiconductor switch on the second section, wherein the semiconductor switch is electrically coupled to the first and third sections;and the electrically conductive signal pin on the fourth portion, wherein the fourth portion is electrically coupled to the third portion, and wherein the signal pin is configured to electrically couple the power module to the external device.;

[0027] The first plate may have a thickness between 100 µm and 1 cm and / or the second plate may have a thickness between 1 µm and 1 mm. For example, the first plate may have a thickness between 500 µm and 5 mm and / or the second plate may have a thickness between 35 µm and 500 µm.

[0028] The first and / or second plate comprises or is / are made of, for example, copper. Alternatively or additionally, the carrier comprises or consists of one or more layers of pre-impregnated fibers.

[0029] Optionally, the electronic component is arranged on the third section and is electrically coupled to the semiconductor switch and the fourth section. Furthermore, the power module can comprise the heat sink on which the carrier is arranged.

[0030] These and other aspects of the invention will become apparent and explained with reference to the embodiments described below. Embodiments of the present invention will be described in more detail below with reference to the attached drawings. Fig. 1 shows a side view of an example power module. Fig. 2 shows a side view of embodiments of plates of the power module of Fig. 1. Fig. 3 shows a side view of the plates of Fig. 2, which is mounted on a power module carrier of Fig. 1 are arranged. Fig. 4 shows a side view of the plates on the support of Fig. 3 with an embodiment of a vacuum film. Fig. 5 shows a side view of the Fig. 4, which is arranged in a chamber of an autoclave.

[0031] The reference symbols used in the drawings and their meanings are summarized in the following list of reference symbols. Identical parts in the figures are generally provided with the same reference symbols.

[0032] Fig. 1 shows a side view of an example of a power module 20. The power module 20 includes a carrier 22, an electrically conductive first plate 24 above the carrier 22, an electrically conductive second plate 26 above the carrier 22 adjacent to the first plate 24, at least one semiconductor switch, e.g., a first semiconductor switch 60 and a second semiconductor switch 62, disposed on the first plate 24 and electrically coupled to the second plate 26, and optionally a heat sink 28 below the carrier 22. The power module 20 may form a half-bridge and / or may be disposed in a rectifier or inverter.

[0033] The first and / or second plates 24, 26 may comprise or be made of copper. The carrier 22 may comprise or be made of one or more layers of pre-impregnated fibers. The carrier 22 may be electrically insulating. The heat sink 28 may comprise or be made of aluminum. The heat sink 28 may include one or more cooling fins (not shown in the figures).

[0034] Optionally, the first plate 24 may be separated into a first portion 50 and a second portion 52, such that a first gap 34 is formed between the first portion 50 and the second portion 52. The first gap 34 may extend from a side of the first plate 24 facing away from the support 20 to the support 20. The first gap 34 may be formed by sawing and / or correspond to a saw cut.

[0035] Optionally, the second plate 26 can also be separated into a third section 54 and a fourth section 56, so that a second gap 36 is formed between the third section 54 and the fourth section 56. The second gap 36 can extend from a side of the second plate 26 facing away from the support 20 to the support 20. The second gap 36 can be formed by sawing and / or correspond to a saw cut.

[0036] The first and second semiconductor switches 60, 62 can be arranged on the second section 52. The first semiconductor switch 60 can be electrically coupled to the first section 50, for example, by a wire bond 68. The first semiconductor switch 60 can also be electrically coupled to the second section 52, for example, by an electrical contact (not shown) of the first semiconductor switch 60 on an underside of the first semiconductor switch 60. Furthermore, the first semiconductor switch 60 can be electrically coupled to the second semiconductor switch 62, for example, by another wire bond 68. The second semiconductor switch 62 can be electrically coupled to the second section 52, for example, by an electrical contact (not shown) of the second semiconductor switch 62 on an underside of the second semiconductor switch 62. Furthermore, the second semiconductor switch 62 can, for example,be electrically coupled to the third section 54 by another wire bond 68.

[0037] At least one of the semiconductor switches 60, 62 may be a high-power semiconductor chip. The high-power semiconductor chip may be configured to process high voltages, for example, more than 100 V, and / or high currents, for example, more than 10 A. The semiconductor switches 60, 62 may comprise SiC, GaN, or GaO. The semiconductor switches 60, 62 may each be a transistor, e.g., a FWD, an IGBT, and / or a MOSFET.

[0038] Optionally, an electronic component 64 for controlling the first and / or second semiconductor switches 60, 62 can be arranged on the third section 54. The electronic component 64 can be electrically coupled, for example, to the second semiconductor switch 62 by another wire bond 68 and / or, for example, to the fourth section 56 by one or more further wire bonds (not shown). The electronic component 64 can comprise a chip for controlling the semiconductor switches 60, 62.

[0039] The first plate 24 has a first thickness H1, and the second plate 26 has a second thickness H2 (see Fig. 1 and Fig. 2). The first thickness H1 is greater than the second thickness H2. The first thickness H2 can be in a range from 100 µm to 1 cm, e.g., from 500 µm to 5 mm, e.g., from 1 mm to 3 mm. The second thickness H2 can be in a range from 1 µm to 1 mm, e.g., from 10 µm to 500 µm, e.g., from 35 µm to 500 µm.

[0040] The semiconductor switches 60, 62 arranged on the thicker first plate 24, in particular the thicker second section 52, can be used for currents greater than the currents for which the electronic component 64 on the thinner second plate 26, in particular the thinner third section 54, can be used. For example, the first and second semiconductor switches 24, 26 can be configured to handle currents greater than 10 A, and the electronic component 64 can be configured to handle currents less than or equal to 10 A. In this context, the first plate 24 can be referred to as a "power pattern," and the second plate 26 can be referred to as a "signal pattern."

[0041] If no high-power semiconductor switch 60, 62 is arranged on the first section 50, the first section 50 can optionally be formed from the second plate 26 and / or from another plate with the second thickness H2. Alternatively or additionally, the second section 52 can be divided into two or more subsections that are spaced apart from one another and electrically insulated from one another, wherein each of the semiconductor switches 60, 62 can be arranged on a different one of the subsections.

[0042] An electrically conductive contact pin 66 may be disposed on and electrically coupled to the second plate 26, particularly the fourth portion 56. The contact pin 66 may be provided for mechanically and / or electrically coupling the power module 20 to a driver or driver board (not shown) of the power module 20 and / or an external device, e.g., a battery or a load.

[0043] Optionally, the power module 20 may be embedded in a potting body (not shown), e.g., by potting. The potting body may provide a housing for the power module 20.

[0044] The Fig. 2 to 5 show different states of the power module 20 during a method for forming the power module 20, wherein Fig. 1 shows the final state of the power module 20. Furthermore, the Fig. 1 to 5 are used to describe several steps of the process.

[0045] Fig. Figure 2 shows a side view of embodiments of the plates 24, 26 of the power module of Fig. 1. In particular, Fig. 2 shows a state of the method for forming the power module 20 in which the first plate 24 having the first thickness H1 and the second plate 26 having the second thickness H2 are provided. Moreover, after providing the plates 24, 26, the first plate 24 is separated into the first portion 50 and the second portion 52, and the second plate 26 is separated into the third portion 54 and the fourth portion 56. The first portion 50 is separated from the second portion 52 by the first gap 34. The third portion 54 is separated from the fourth portion 56 by the second gap 36. The plates 24, 26 can be separated into the corresponding portions 50, 52, 54, 56 by sawing.

[0046] In the Fig. 2, the first and second sections 50, 52 and / or the third and fourth sections 54, 56 may still be coupled to one another optionally in a plane in front of or behind the plane of the drawing and may be completely separated from one another in a later step of the method, e.g. after the plates 24, 26 have been fixed to the carrier 22 and before the power module 20 has been completed.

[0047] Fig. 3 shows a side view of the plates 24, 26 of Fig. 2, which are mounted on the carrier 22 of the power module 20 of Fig. 1 are arranged. Optionally, the carrier 22 can be arranged on the heat sink 28, in particular before or after arranging the plates 24, 26 on the carrier 22.

[0048] Fig. 4 shows a side view of the plates 24, 26 on the support 22 of Fig. 3 with an embodiment of a vacuum film 70. The vacuum film 70 is arranged at least above the carrier 22 and the plates 24, such that a cavity 78 is formed at least between the plates 24, 26 and the vacuum film 70 and optionally between the exposed parts of the carrier 22 in the gaps 34, 36 and the vacuum film 70.

[0049] The vacuum film 70 can be gas-tightly coupled to a lateral side surface of the carrier 22 or to a bottom side 30 of the carrier 22, such that at least a portion of the bottom side 30 of the carrier 22 is free of the vacuum film 70. Alternatively, the vacuum film 70 can be arranged to completely enclose the carrier 22 and the plates 24, 26. When the heat sink 28 is arranged, the vacuum film 70 can also completely or partially enclose the heat sink 28. In the latter case, the vacuum film 70 can, for example, be arranged to be gas-tightly coupled to a bottom side 32 of the heat sink 28, with the bottom side 32 of the heat sink 28 facing away from the carrier 22. The vacuum film 70 can be gas-tightly coupled to the bottom side 32 of the heat sink 28 by a vacuum sealing means 74.If the heat sink 28 is not arranged, the vacuum film 70 can be coupled gas-tight to the underside 30 of the carrier 22 by the vacuum sealing means 74.

[0050] A gas outlet 72 for evacuating the cavity 78 can extend through the vacuum film 70. The cavity 78 can be sealed gas-tight with the exception of the gas outlet 72. Thus, the gas outlet 72 can be coupled gas-tight to the vacuum film 70. The gas outlet 72 can be coupled to the vacuum film 70 before or after the vacuum film 70 is arranged over the carrier 22, the plate 24, and optionally the heat sink 28. The gas outlet 72 can be configured to communicate with the cavity 78 and with a vacuum pump (not shown) for evacuating the cavity 78. The gas outlet 72 can extend from the cavity 78 to the vacuum pump. The cavity 78 can be evacuated by the vacuum pump via the gas outlet 72.

[0051] Fig. 5 shows a side view of the Fig. 4, which is arranged in a chamber 82 of an autoclave 80. In this stage of the process, the cavity 78 between the carrier 22, the plates 24, 26, and the vacuum film 70 is evacuated, as can be seen from the vacuum film 70, which clings to the plates 24, 26, the carrier 22, at least partially into the gap 34, and optionally the heat sink 28. The chamber 82 can be pressurized with a gas, e.g., air, via a gas inlet 76 of the autoclave 80, so that an overpressure can be generated in the chamber 82, the gas having a temperature high enough to fix the plates 24, 26 to the carrier 22. The positive pressure of the gas in the chamber 82 and the negative pressure in the cavity 78 can provide a predetermined pressure on the plates 24, 26 to the carrier 22, so that the plates 24, 26 are fixed to the carrier 22.Once the heat sink 28 is positioned, the carrier 22 is further pressed against the heat sink 28, and the heat sink 28 is fixed to the carrier 22. Optionally, an adhesive may be provided between the plates 24, 26 and the carrier 22 and / or between the carrier 22 and the heat sink 28.

[0052] After a predetermined period of time sufficient to properly fix the plates 24, 26 to the carrier 42, the gas is released from the chamber 82. Thereafter, the carrier 22 and the plates 24, 26 surrounded by the vacuum film 70 can be removed from the chamber 82, and the vacuum film 70 can be removed from the carrier 22, the plates 24, 26, and optionally the heat sink 28.

[0053] After evacuating the cavity 78, e.g., by the vacuum pump, and before pressurizing the chamber 82, the gas outlet 72 can be closed and disconnected from the vacuum pump. Alternatively, the gas outlet 72 can be coupled to the vacuum pump until the carrier 22, the plates 24, 26, and optionally the heat sink 28 with the vacuum film 70 are removed from the chamber 82.

[0054] The high gas temperature in the chamber 82 can be between 50°C and 200°C, e.g., between 80°C and 150°C, e.g., at 120°C. The overpressure in the pressurized chamber 82 can be between 10 kPa and 100 kPa, e.g., between 30 kPa and 60 kPa above atmospheric pressure. Alternatively or additionally, the negative pressure in the evacuated space can be between 10 -3 hPa and 10 -6 hPa, e.g. between 10 -4 hPa and 10 -6 hPa, lie.

[0055] Then, the semiconductor switches 24, 26 can be arranged on the second section 52, and optionally the electronic component 64 can be arranged on the third section 54, as shown in Fig. 1. Furthermore, the signal pin 66 can be arranged, e.g., by soldering or gluing, on the second plate 26, in particular on the fourth section 56, as shown in Fig. 1. Finally, wire bonds 68 may be arranged to electrically couple the first portion 50 to the first semiconductor switch 60, the first semiconductor switch 60 to the second semiconductor switch 62, the second semiconductor switch 62 to the electronic component 64, and / or the electronic component 64 to the fourth portion 56 and, via the fourth portion 56, to the signal pin 66.

[0056] Alternatively, there may be more or fewer semiconductor switches 60, 62, electronic components 64, corresponding plates 24, 26, in particular corresponding sections 50, 52, 54, 56, and / or corresponding wire bonds 28. List of reference symbols 20 power module 22 carriers 24 first record 26 second plate 28 heat sinks 30 Underside of the carrier 32 Bottom of the heatsink 34 first gap 36 second gap 50 first section 52 second section 54 third section 56 fourth section 60 first semiconductor switch 62 second semiconductor switch 64 electronic component 66 contact pin 68 wire bond 70 vacuum film 72 Gas outlet 74 Vacuum sealants 76 Gas inlet 78 cavity 80 Autoclave 82 Chamber H1 - H2 thickness one and two

Claims

[1] A method of forming a power module (20), the method comprising the following steps: Providing a carrier (22); Arranging an electrically conductive first plate (24) on the carrier (22); Arranging an electrically conductive second plate (26) next to the first plate (24) on the carrier (22), wherein the first plate (24) has a first thickness (H1) and the second plate (26) has a second thickness (H2) and wherein the first thickness (H1) is greater than the second thickness (H2); Arranging a vacuum film (70) over the carrier (22), the first plate (24) and the second plate (26) such that a cavity (78) is formed at least between the plates (24, 26) and the vacuum film (70), wherein a gas outlet (72) for evacuating the cavity (78) extends through the vacuum film (70), and that the cavity (78) is sealed gas-tight with the exception of the gas outlet (72); Arranging the carrier (22) and the plates (24, 26) with the vacuum film (70) in a chamber (82) of an autoclave (80); Evacuating the cavity (78) between the plates (24, 26) and the vacuum film (70); Pressurizing the chamber (82) with gas having a temperature sufficient to fix the plates (24, 26) to the carrier (22); Releasing the gas from the chamber (82); Removing the carrier (22) and the plates (24, 26) with the vacuum film (70) from the chamber (82); Removing the vacuum film (70) from the carrier (22) and the plates (24, 26); Arranging at least one semiconductor switch (60, 62) on the first plate (24); and electrically coupling the semiconductor switch (60, 62) to the second plate (26). [2] A method according to claim 1, comprising, before arranging the plates (24, 46) on the carrier (22): Separating the first plate (24) into a first portion (50) and a second portion (52) such that the first portion (50) is electrically insulated from and spaced apart from the second portion (52), wherein the semiconductor switch (60, 62) is disposed on the second portion (50) and is electrically coupled to the first portion (50). [3] Method according to claim 2, comprising, before arranging the plates (24, 26) on the support (22): Separating the second plate (26) into a third section (54) and a fourth section (56) such that the third section (54) is electrically insulated from and spaced from the fourth section (56). [4] Method according to one of claims 2 or 3, wherein the first and / or second plate (24, 26) are separated by sawing into the corresponding sections (50, 52, 54, 56). [5] Method according to one of the preceding claims, wherein the vacuum film (70) is arranged such that it is coupled in a gas-tight manner to a bottom side (30) of the carrier (22), the bottom side (30) of the carrier (22) facing away from the semiconductor chip (24, 26). [6] Method according to claim 5, wherein the vacuum film (70) is coupled gas-tight to the underside (30) of the carrier (22) by a vacuum sealing means (74). [7] Method according to one of the preceding claims, wherein the gas temperature in the chamber (82) is between 50°C and 200°C and / or an overpressure in the pressurised chamber (82) is between 10 kPa and 100 kPa above atmospheric pressure, and / or a negative pressure in the evacuated cavity (78) between 10 -3 hPa and 10 -8 hPa. [8] The method of claim 7, wherein the semiconductor switch (60, 62) is electrically coupled to the first and / or third portion (50, 54) by at least one wire bond (68). [9] Method according to one of the preceding claims, wherein the first plate (24) has a thickness between 100 µm and 1 cm; and / or the second plate (26) has a thickness between 1 µm and 1 mm. [10] A method according to any one of the preceding claims, wherein the first and / or second plate (24, 26) comprises or is made of copper. [11] A method according to any one of the preceding claims, wherein the carrier (22) comprises or consists of one or more layers of pre-impregnated fibers. [12] Method according to one of claims 3 to 11, comprising: Disposing an electrically conductive signal pin (66) on the fourth portion (56), the signal pin (66) being configured to electrically couple the power module (20) to an external device.

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