WO2023208331A1

WO2023208331A1 - Power module with heat conductive anti-corrosion coating, power module cooling arrangement and method for its production

Info

Publication number: WO2023208331A1
Application number: PCT/EP2022/061137
Authority: WO
Inventors: Frank Winter; Holger Torwesten
Original assignee: Huawei Digital Power Technologies Co., Ltd.
Priority date: 2022-04-27
Filing date: 2022-04-27
Publication date: 2023-11-02

Abstract

The disclosure relates to a power module (100), comprising: a first module side (111) and a second module side (112) opposing the first module side (111); a mold body (110) arranged between the first module side (111) and the second module side (112); at least one semiconductor chip embedded within the mold body (110); wherein the second module side (112) comprises a metal layer (130) forming a heat dissipation surface of the power module (100); a coolant channel (143) comprising a coolant (145) for cooling the heat dissipation surface of the power module (100); and a heat conductive anti-corrosion coating (114) deposited on the metal layer (130), the heat conductive anti-corrosion coating (114) being provided to shield the metal layer (130) from the coolant (145) in order to prevent corrosion of the metal layer (130). The disclosure further relates to a power module cooling arrangement using stacked power modules (100) and a method for producing such power module (100).

Description

POWER MODULE WITH HEAT CONDUCTIVE ANTI-CORROSION COATING, POWER MODULE COOLING ARRANGEMENT AND METHOD FOR ITS PRODUCTION

TECHNICAL FIELD

The disclosure relates to the field of power modules and cooling strategies for power modules. In particular, the disclosure relates to direct liquid cooling of a power module and an array of power modules for better thermal performance and higher power densities. The disclosure further relates to protection of substrate of direct cooled power module immersed directly into cooling liquid against electro-chemical and mechanical attack.

BACKGROUND

Cooling of power modules is important in order to protect the power modules against overheating and to extend lifespan of the power modules. In orderto increase power density and efficiency in next generation power modules and packages, a very good thermal and electrical management is essential. Up to now, the cooling of the power modules is either indirect by using a thermal interface material or direct with an isolating cooler firmly attached to the power module. Disadvantage of such cooling concepts is in both cases a higher thermal resistance (Rth) and increased junction temperatures for the devices and therefore a lower power rating of the module.

SUMMARY

This disclosure provides a solution for a cooled power module without the above-described disadvantages.

In particular, this disclosure presents a solution for a cooled power module with improved thermal resistance (Rth) and improved power rating. The thermal resistance of such power module is significantly reduced.

The foregoing and other objects are achieved by the features of the independent claims. Further implementation forms are apparent from the dependent claims, the description and the figures. The problem of the higher thermal resistance, Rth, is solved by merging an array of modules directly into the cooling liquid with a suitable sealing device and a protective and isolating, high temperature stable coating of the single modules that can guarantee full covered functionality of the array. Instead of the array of modules, a single module coated with the protective and isolating, high temperature stable coating can equally be used.

The solution presented in this disclosure achieves the above-described objects at a feasible cost by enabling all or at least most of the available heat sinks of the module, e.g., Cu, EMC, Al, etc., as direct contact to the cooling liquid by covering them with a thin protective layer. The protective layer is designed to protect against electro-chemical attack and for mechanical protection and electrical isolation.

The disclosure relates to a power module according to a first aspect, a power module cooling arrangement according to a second aspect, a method for producing a power module according to a third aspect, a computer program product according to a fourth aspect and a computer-readable medium according to a fifth aspect, as described in the following.

According to the first aspect, the disclosure relates to a power module, comprising: a first module side and a second module side opposing the first module side; a mold body arranged between the first module side and the second module side; at least one semiconductor chip embedded within the mold body; wherein the second module side comprises a metal layer forming a heat dissipation surface of the power module; a coolant channel comprising a coolant for cooling the heat dissipation surface of the power module; and a heat conductive anti-corrosion coating deposited on the metal layer, the heat conductive anti-corrosion coating being provided to shield the metal layer from the coolant in order to prevent corrosion of the metal layer.

Such a power module provides the advantage that due to the heat conductive anti-corrosion coating deposited on the metal layer, the metal layer can be directly cooled by the coolant which results in better cooling characteristics and improved thermal dissipation. By this direct cooling concept, the thermal resistance can be decreased which results in a better cooling of the power module. The heat conductive anti-corrosion coating protects the metal layer from the coolant. The coolant may be an aggressive fluid which may harm the metal layer when it is in direct contact with the metal layer, in particular when the coolant is in direct contact with the metal layer for a long period of time. The mold body may comprise electrical outwards connections, also referred to as contact fingers, for electrical connection of the embedded semiconductor chip.

In an exemplary implementation of the power module, the anti-corrosion coating is electrically insulating.

This provides the advantage that a high voltage of the metal layer can be isolated from the coolant channel or cooler body. Hence, the coolant channel carries no dangerous high voltages.

In an exemplary implementation of the power module, the anti-corrosion coating comprises at least one of an atomic layer deposition, ALD, layer, a chemical vapor deposition, CVD, layer or a physical vapor deposition, PVD, layer.

The PVD layer may comprise a thin layer of nanostructures with silicon oxide and/or silicon nitride, for example.

These thin film layers improve the surface properties of the mold body due to their antiresistance, hardness, corrosion resistance, dielectric, optical transparency and further material characteristics.

The anti-corrosion coating serves as protection against electrochemical attack of unnoble metal and enable free choice of cooler body material.

In an exemplary implementation of the power module, the anti-corrosion coating may comprise one ALD layer or a stack comprising multiple ALD layers. For example, the ALD may comprise one layer of AI2O3 30nm, for example in a range from 5 to 100nm, or HfO2 20nm, for example in a range from 5 to 50nm, or stacks from HfO2 and AI2O3. Such structure can be used as a defined ion barrier layer.

In an exemplary implementation of the power module, the anti-corrosion coating is further deposited on at least part of the mold body extending at the second module side.

This provides the advantage that the mold body can be protected by the anti-corrosion coating against harmful environmental influences. This increases the lifespan of the mold body. In an exemplary implementation of the power module, the first module side comprises a second metal layer forming a second heat dissipation surface of the power module, wherein the heat conductive anti-corrosion coating is deposited on both metal layers to shield both metal layers from the coolant in order to prevent corrosion of both metal layers.

This provides the advantage of double-side cooling which increases cooling efficiency. Due to the heat conductive anti-corrosion coating deposited on both metal layers, i.e., at the first module side and the second module side, the metal layers on both sides can be directly cooled by the coolant which results in better cooling characteristics and improved thermal dissipation. The thermal resistance can be decreased which results in a better cooling of such a double-sided cooled power module. The heat conductive anti-corrosion coating protects both metal layers from the coolant.

In an exemplary implementation of the power module, the anti-corrosion coating is further deposited on at least part of the mold body extending at the first module side.

This provides the advantage that the mold body can be protected by the anti-corrosion coating against harmful environmental influences from both module sides. As mentioned above, this increases the lifespan of the mold body.

In an exemplary implementation of the power module, the anti-corrosion coating fully covers the mold body, the metal layer and the second metal layer in order to seal the power module against outside humidity.

This provides the advantage that the power module can be efficiently protected against harmful environmental influences such as outside humidity, etc. which increases the lifespan of the power module.

In an exemplary implementation of the power module, the power module comprises a sealing placed between the coolant channel and the second module side, the sealing being provided to seal the coolant channel against loss of coolant.

The sealing provides the advantage that the coolant channel can be efficiently attached to the power module and the sealing can efficiently seal contact areas between the second module side of the power module and the coolant channel. In an exemplary implementation of the power module, the sealing is configured to provide a hermetically sealing connection with the anti-corrosion coated metal layer and the coolant channel.

This provides the advantage that the sealing allows uneven areas in both, the anti-corrosion coated metal layer and the coolant channel to be sealed well.

In an exemplary implementation of the power module, the sealing is placed between the coolant channel and the anti-corrosion coated metal layer or between the coolant channel and a portion of the anti-corrosion coated mold body extending at the second module side.

This provides the advantage of flexible manufacturing. In the first case when the sealing is placed between the coolant channel and the anti-corrosion coated metal layer, the coating of the metal layer, e.g., by ALD process, can be performed before or after the molding. In the second case when the sealing is placed between the coolant channel and a portion of the anti-corrosion coated mold body, the coating of the mold body should be performed after the molding.

In an exemplary implementation of the power module, the power module comprises a second sealing placed between the coolant channel and the first module side, the second sealing being provided to seal the coolant channel against loss of coolant.

As described above for the sealing, the second sealing provides the advantage that the coolant channel can be efficiently attached to the power module and the second sealing can efficiently seal contact areas between the first module side of the power module and the coolant channel. Thus, the coolant channel may surround the power module for an efficient cooling.

In an exemplary implementation of the power module, the second sealing is placed between the coolant channel and the anti-corrosion coated second metal layer; or between the coolant channel and a portion of the anti-corrosion coated mold body extending at the first module side.

This provides the advantage of flexible manufacturing when applying double side cooling. In the first case when the second sealing is placed between the coolant channel and the anti-corrosion coated second metal layer, the coating of the second metal layer, e.g., by ALD process, can be performed before or after the molding. In the second case when the second sealing is placed between the coolant channel and a portion of the anti-corrosion coated mold body extending at the first module side, the coating of the mold body should be performed after the molding.

According to the second aspect, the disclosure relates to a power module cooling arrangement, comprising: a plurality of power modules according to the first aspect as described above, which are stacked against each other by their respective first module sides and second module sides, the coolant channels of the respective power modules forming a common coolant channel.

By implementing such common coolant channel, the whole array of stacked power modules forming the power module cooling arrangement can be cooled in a very efficient manner, since the cooling liquid of the common coolant channel can flow over the metal layer surfaces of all power modules and thus ensure efficient cooling.

In an exemplary implementation of the power module cooling arrangement, the common coolant channel extends above the first module sides and the second module sides of each of the plurality of power modules.

This arrangement provides for an efficient cooling since the cooling liquid is in direct contact with the first module sides and the second module sides of each power module.

In an exemplary implementation of the power module cooling arrangement, the power module cooling arrangement comprises at least one intermediate sealing being placed between a respective first module side and a respective second module side of two power modules stacked above each other, the at least one intermediate sealing being configured to seal the common coolant channel within the stacked power modules against loss of coolant.

This intermediate sealing provides the advantage that the stacked power modules can also be cooled from module sides which are stacked against each other. The intermediate sealing allows coolant to flow across module sides which are stacked against each other.

In an exemplary implementation of the power module cooling arrangement, each intermediate sealing is placed between the mold bodies or between the metal layers of a respective first module side and a respective second module side of the two stacked power modules. This provides the advantage of flexible manufacturing of the power module cooling arrangement. In the first case when the intermediate sealings are placed between the mold bodies of a respective first module side and a respective second module side, the coating, e.g., by ALD process, should be performed after the molding. In the second case when the intermediate sealings are placed between the metal layers of a respective first module side and a respective second module side, the coating, e.g., by ALD process, can be performed before or after the molding.

These intermediate sealings may be formed by a sealing mesh, e.g., by a rubber mesh that is properly designed.

According to the third aspect, the disclosure relates to a method for producing a power module, the method comprising: molding at least one semiconductor chip within a mold body to form a power module having a first module side and a second module side opposing the first module side, the mold body being arranged between the first module side and the second module side; forming a heat dissipation surface of the power module at the second module side by a metal layer; depositing a heat conductive anti-corrosion coating on the metal layer to shield the metal layer from the coolant in order to prevent corrosion of the metal layer; and providing a coolant channel comprising a coolant for cooling the heat dissipation surface of the power module.

Such a method allows to produce a power module as described above for the first aspect. The power module produced by this method provides the advantages as described above for the first aspect. I.e., due to the heat conductive anti-corrosion coating deposited on the metal layer, the metal layer can be directly cooled by the coolant which results in better cooling characteristics and improved thermal dissipation. The thermal resistance can be decreased which results in a better cooling of the power module. The heat conductive anticorrosion coating protects the metal layer from the coolant.

In an exemplary implementation of the method, the anti-corrosion coating is deposited on the metal layer and/or the mold body before or after the molding.

This provides the advantage of flexible design options. Depending on the respective design, production steps can be saved in order to reduce costs. According to the fourth aspect, the disclosure relates to a computer program product including computer executable code or computer executable instructions that, when executed, causes at least one computer to execute the method according to the third aspect described above.

The computer program product may run on a controller or a processor for implementing the above method to produce the power module according to the first aspect and/or the power module cooling arrangement according to the second aspect described above.

According to a fifth aspect, the disclosure relates to a computer-readable medium, storing instructions that, when executed by a computer, cause the computer to execute the method according to the third aspect described above. Such a computer readable medium may be a non-transient readable storage medium. The instructions stored on the computer- readable medium may be executed by a controller or a processor.

BRIEF DESCRIPTION OF THE DRAWINGS

Further embodiments of the disclosure will be described with respect to the following figures, in which:

Figure 1 shows a cross section of a power module 100 according to a first embodiment;

Figure 2 shows a cross section of a power module 200 according to a second embodiment;

Figure 3 shows a cross section of a power module cooling arrangement 300 according to a first embodiment;

Figure 4 shows a cross section of a power module cooling arrangement 400 according to a second embodiment; and

Figure 5 shows a schematic diagram illustrating a method 500 for producing a power module according to the disclosure. DETAILED DESCRIPTION OF EMBODIMENTS

In the following detailed description, reference is made to the accompanying drawings, which form a part thereof, and in which is shown by way of illustration specific aspects in which the disclosure may be practiced. It is understood that other aspects may be utilized and structural or logical changes may be made without departing from the scope of the disclosure. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the disclosure is defined by the appended claims.

It is understood that comments made in connection with a described method may also hold true for a corresponding device or system configured to perform the method and vice versa. For example, if a specific method step is described, a corresponding device may include a unit to perform the described method step, even if such unit is not explicitly described or illustrated in the figures. Further, it is understood that the features of the various exemplary aspects described herein may be combined with each other, unless specifically noted otherwise.

A power module or power electronic module as described in this disclosure provides the physical containment for several power components, such as power semiconductor devices. These power semiconductors, also referred to as dies, may be soldered or sintered on a power electronic substrate that carries the power semiconductors, provides electrical and thermal contact and electrical insulation where needed. Compared to discrete power semiconductors in plastic housings, power packages provide a higher power density and are in many cases more reliable.

Figure 1 shows a cross section of a power module 100 according to a first embodiment.

The concept of this first embodiment can be summarized as follows: In this first embodiment, the sealing of the cooler body, also called “coolant channel 143” hereinafter against water leakage is done on the Cu surface, or in more general notation the metal layer 130 as shown in Figure 1. The ALD layer, also called in more general terms, the heat conductive anticorrosion coating 114, serves as protection against electrochemical attack of unnoble metal, and enables free choice of cooler body material. The ALD process can be done before or after molding. In the following, this first embodiment of the power module 100 is described in detail.

The power module 100 comprises a first module side 111 and a second module side 112 opposing the first module side 111 ; and a mold body 110 arranged between the first module side 111 and the second module side 112. The power module 100 comprises at least one semiconductor chip embedded within the mold body 110. The second module side 112 comprises a metal layer 130 forming a heat dissipation surface of the power module 100. The power module 100 comprises a coolant channel 143 comprising a coolant 145 for cooling the heat dissipation surface of the power module 100. The power module 100 further comprises a heat conductive anti-corrosion coating 114 deposited on the metal layer 130. The heat conductive anti-corrosion coating 114 is provided to shield the metal layer 130 from the coolant 145 in order to prevent corrosion of the metal layer 130.

The mold body 110 may comprise electrical outwards connections 113, also referred to as contact fingers, for electrical connection of the embedded semiconductor chip. The electrical outwards connections 113 described above may be part of a leadframe, for example.

The anti-corrosion coating 114 may be electrically insulating. The anti-corrosion coating 114 may comprise, for example, at least one of an atomic layer deposition, ALD, layer, a chemical vapor deposition, CVD, layer or a physical vapor deposition, PVD, layer.

Atomic layer deposition (ALD) is a thin-film deposition technique based on the sequential use of a gas-phase chemical process; it is a subclass of chemical vapor deposition. The majority of ALD reactions use two chemicals called precursors (also called "reactants"). These precursors react with the surface of a material one at a time in a sequential, selflimiting, manner. A thin film is slowly deposited through repeated exposure to separate precursors. ALD is a key process in fabricating semiconductor devices, and part of the set of tools for synthesizing nanomaterials.

The anti-corrosion coating may comprise one ALD layer or a stack comprising multiple ALD layers. For example, the ALD may comprise one layer of AI2O3 30nm (e.g., in a range of 5 to 100nm) or HfO2 20nm (e.g., in a range of 5 to 50nm) or stacks from HfO2 and AI2O3. Such structure can be used as a defined ion barrier layer.

Chemical vapor deposition (CVD) is a vacuum deposition method used to produce high quality, and high-performance, solid materials. The process can be used in the semiconductor industry to produce thin films. In typical CVD, the wafer (substrate) is exposed to one or more volatile precursors, which react and/or decompose on the substrate surface to produce the desired deposit. Frequently, volatile by-products are also produced, which are removed by gas flow through the reaction chamber.

Physical vapor deposition (PVD) describes a variety of vacuum deposition methods which can be used to produce thin films and coatings. PVD is characterized by a process in which the material goes from a condensed phase to a vapor phase and then back to a thin film condensed phase. The most common PVD processes are sputtering and evaporation. PVD is used in the manufacture of items which require thin films for mechanical, optical, chemical or electronic functions.

The anti-corrosion coating 114 may be further deposited on at least part of the mold body 110 extending at the second module side 112.

The electrical outwards connections 113 may not be covered by the heat conductive anticorrosion coating 114 if this coating is electrically insulating. When a heat conductive anticorrosion coating 114 is applied that is electrically conductive, the electrical outwards connections 113 may also be covered by the heat conductive anti-corrosion coating 114.

The first module side 111 may comprise a second metal layer 120 forming a second heat dissipation surface of the power module 100. Such a power module corresponds to a double side cooling module. The heat conductive anti-corrosion coating 114 may be deposited on both metal layers 130, 120 to shield both metal layers 130, 120 from the coolant 145 in order to prevent corrosion of both metal layers 130, 120.

The anti-corrosion coating 114 may further be deposited on at least part of the mold body 110 extending at the first module side 111. The anti-corrosion coating 114 may fully cover the mold body 110, the metal layer 130 and the second metal layer 120 in order to seal the power module 100 against outside humidity.

The power module 100 may comprise a sealing 141 placed between the coolant channel 143 and the second module side 112. The sealing 141 may be provided to seal the coolant channel 143 against loss of coolant 145.

The sealing 141 may be configured to provide a hermetically sealing connection with the anti-corrosion coated 114 metal layer 130 and the coolant channel 143.

The sealing 141 may be placed between the coolant channel 143 and the anti-corrosion coated 114 metal layer 130.

In an alternative embodiment, i.e., the second embodiment as shown in Figure 2, the sealing 141 may be placed between the coolant channel 143 and a portion of the anti-corrosion coated 114 mold body 110 extending at the second module side 112

In an alternative embodiment, not shown in Figure 1 but shown in Figure 3, the power module 100 may comprise a second sealing 241 placed between the coolant channel 143 and the first module side 111. The second sealing 241 may be provided to seal the coolant channel 143 against loss of coolant 145.

The second sealing 241 may be placed between the coolant channel 143 and the anticorrosion coated 114 second metal layer 120 as shown in Figure 3. Alternatively, the second sealing 241 may be placed between the coolant channel 143 and a portion of the anticorrosion coated 114 mold body 110 extending at the first module side 111 , as shown in Figure 4.

The sealing 141 may be a sealing ring having a circular shape or a rectangular or square shape. The sealing 141 may be made of rubber or plastic. The sealing 141 may have an upper part to engage in the coated metal layer 130 and a lower part to engage in the coolant channel 143, e.g., a main body of the coolant channel 143. The sealing 141 may have a middle part between the upper part and the lower part to immerse in the coolant 145 in order to seal the coolant 145 in the coolant channel 143 from the outside environment and to avoid loss of coolant 145. The coolant 145 may be water or oil or any other type of coolant used for cooling vehicles, for example.

Figure 2 shows a cross section of a power module 200 according to a second embodiment.

The concept of this second embodiment can be summarized as follows: In this second embodiment, the sealing 141 of the cooler body, also called “coolant channel 143” is done, as a difference to embodiment 1 , on the mold body 110 surface, where the ALD, i.e., the heat conductive anti-corrosion coating 114 in more general terms, serves as protection against humidity seeping into the mold compound, i.e., the mold body 110. This increases the possible cooled areas, and reduced stress on ceramic isolation, improving performance and lifetime. The ALD process can be done after molding.

The basic structure of the second embodiment of the power module 200 is similar to the first embodiment illustrated in Figure 1. That means, the power module 200 comprises a first module side 111 and a second module side 112 opposing the first module side 111 ; and a mold body 110 arranged between the first module side 111 and the second module side 112. The power module 200 comprises at least one semiconductor chip embedded within the mold body 110. The second module side 112 comprises a metal layer 130 forming a heat dissipation surface of the power module 200. The power module 200 comprises a coolant channel 143 comprising a coolant 145 for cooling the heat dissipation surface of the power module 200. The power module 200 further comprises a heat conductive anticorrosion coating 114 deposited on the metal layer 130. The heat conductive anti-corrosion coating 114 is provided to shield the metal layer 130 from the coolant 145 in order to prevent corrosion of the metal layer 130.

Figure 3 shows a cross section of a power module cooling arrangement 300 according to a first embodiment.

The concept of this first embodiment of the power module cooling arrangement 300 can be summarized as follows: In this first embodiment, an array of modules (in this exemplary case 3 modules, however any other number can be used as well), as described above with respect to Figures 1 and 2, is stacked in a single cooler for full 6-pack configuration. It understands that any other configuration may be used as well. The sealing is done on the Cu surfaces, i.e. the metal layers 120, 130 in more general terms, of the substrates. A fitting sealing construct is provided to guarantee the waterflow also in between the modules 100. This can be done e.g., by a properly designed rubber mesh. The ALD process can be done before or after molding.

In the following, this first embodiment of the power module cooling arrangement 300 is described in detail.

The power module cooling arrangement 300 comprises a plurality of power modules 100 as described above with respect to Figure 1 , which are stacked against each other by their respective first module sides 111 and second module sides 112. The coolant channels 143 of the respective power modules 100 are forming a common coolant channel 243.

The common coolant channel 243 may extend above the first module sides 111 and the second module sides 112 of each of the plurality of power modules 100.

The power module cooling arrangement 300 may further comprise: at least one intermediate sealing 341 placed between a respective first module side 111 and a respective second module side 112 of two power modules 100 stacked above each other. The at least one intermediate sealing 341 is configured to seal the common coolant channel 243 within the stacked power modules 100 against loss of coolant 145.

Each intermediate sealing 341 may be placed between the metal layers 130, 120 of a respective first module side 111 and a respective second module side 112 of the two stacked power modules 100 as shown in Figure 3.

In an alternative embodiment as shown in Figure 4, i.e., the second embodiment of the power module cooling arrangement 400, each intermediate sealing 341 may be placed between the mold bodies 110 of two stacked power modules 100.

Figure 4 shows a cross section of a power module cooling arrangement 400 according to a second embodiment.

The concept of this second embodiment of the power module cooling arrangement 400 can be summarized as follows: In this second embodiment, an array of modules (in this exemplary case 3 modules, however any other number can be used as well) is stacked in a single cooler for a full 6-pack configuration. It understands that any other configuration than 6-pack can be used as well. The sealing can be done on the mold body 110. The ALD process can be done after molding. The basic structure of the second embodiment of the power module cooling arrangement 400 is similar to the first embodiment illustrated in Figure 3. That means, the power module cooling arrangement 400 comprises a plurality of power modules 200 as described above with respect to Figure 2, which are stacked against each other by their respective first module sides 111 and second module sides 112. The coolant channels 143 of the respective power modules 200 are forming a common coolant channel 243.

The common coolant channel 243 may extend above the first module sides 111 and the second module sides 112 of each of the plurality of power modules 200.

The power module cooling arrangement 400 may further comprise: at least one intermediate sealing 341 placed between a respective first module side 111 and a respective second module side 112 of two power modules 200 stacked above each other. The at least one intermediate sealing 341 is configured to seal the common coolant channel 243 within the stacked power modules 200 against loss of coolant 145.

Each intermediate sealing 341 may be placed between the mold bodies 110 of two stacked power modules 200.

Figure 5 shows a schematic diagram illustrating a method 500 for producing a power module according to the disclosure. The method may produce the power module 100 or the power module 200, for example, as described above with respect to Figures 1 and 2.

The method 500 comprises: molding 501 at least one semiconductor chip within a mold body 110 to form a power module 100, 200 having a first module side 111 and a second module side 112 opposing the first module side 111 , the mold body 110 being arranged between the first module side 111 and the second module side 112.

The method 500 comprises: forming 502 a heat dissipation surface of the power module 100, 200 at the second module side 112 by a metal layer 130, e.g., as described above with respect to Figures 1 and 2.

The method 500 comprises: depositing 503 a heat conductive anti-corrosion coating 114 on the metal layer 130 to shield the metal layer 130 from the coolant 145 in order to prevent corrosion of the metal layer 130, e.g., as described above with respect to Figures 1 and 2. The method 500 comprises: providing 504 a coolant channel 143 comprising a coolant 145 for cooling the heat dissipation surface of the power module 100, 200, e.g., as described above with respect to Figures 1 and 2.

The anti-corrosion coating 114 may be deposited 503 on the metal layer 130 and/or the mold body 110 before or after the molding 501 , e.g., as described above with respect to Figures 1 and 2.

While a particular feature or aspect of the disclosure may have been disclosed with respect to only one of several implementations, such feature or aspect may be combined with one or more other features or aspects of the other implementations as may be desired and advantageous for any given or particular application. Furthermore, to the extent that the terms "include", "have", "with", or other variants thereof are used in either the detailed description or the claims, such terms are intended to be inclusive in a manner similar to the term "comprise". Also, the terms "exemplary", "for example" and "e.g." are merely meant as an example, rather than the best or optimal. The terms “coupled” and “connected”, along with derivatives may have been used. It should be understood that these terms may have been used to indicate that two elements cooperate or interact with each other regardless whether they are in direct physical or electrical contact, or they are not in direct contact with each other.

Although specific aspects have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific aspects shown and described without departing from the scope of the disclosure. This application is intended to cover any adaptations or variations of the specific aspects discussed herein.

Although the elements in the following claims are recited in a particular sequence with corresponding labeling, unless the claim recitations otherwise imply a particular sequence for implementing some or all of those elements, those elements are not necessarily intended to be limited to being implemented in that particular sequence.

Many alternatives, modifications, and variations will be apparent to those skilled in the art in light of the above teachings. Of course, those skilled in the art readily recognize that there are numerous applications of the disclosure beyond those described herein. While the disclosure has been described with reference to one or more particular embodiments, those skilled in the art recognize that many changes may be made thereto without departing from the scope of the disclosure. It is therefore to be understood that within the scope of the appended claims and their equivalents, the disclosure may be practiced otherwise than as specifically described herein.

Claims

CLAIMS:

1. A power module (100, 200), comprising: a first module side (111) and a second module side (112) opposing the first module side (111); a mold body (110) arranged between the first module side (111) and the second module side (112); at least one semiconductor chip embedded within the mold body (110); wherein the second module side (112) comprises a metal layer (130) forming a heat dissipation surface of the power module (100); a coolant channel (143) comprising a coolant (145) for cooling the heat dissipation surface of the power module (100); and a heat conductive anti-corrosion coating (114) deposited on the metal layer (130), the heat conductive anti-corrosion coating (114) being provided to shield the metal layer (130) from the coolant (145) in order to prevent corrosion of the metal layer (130).

2. The power module (100, 200) of claim 1 , wherein the anti-corrosion coating (114) is electrically insulating.

3. The power module (100, 200) of claim 1 or 2, wherein the anti-corrosion coating (114) comprises at least one of an atomic layer deposition, ALD, layer, a chemical vapor deposition, CVD, layer or a physical vapor deposition, PVD, layer.

4. The power module (100, 200) of any of the preceding claims, wherein the anti-corrosion coating (114) is further deposited on at least part of the mold body (110) extending at the second module side (112).

5. The power module (100, 200) of any of the preceding claims, wherein the first module side (111) comprises a second metal layer (120) forming a second heat dissipation surface of the power module (100), wherein the heat conductive anti-corrosion coating (114) is deposited on both metal layers (130, 120) to shield both metal layers (130, 120) from the coolant (145) in order to prevent corrosion of both metal layers (130, 120).

6. The power module (100, 200) of claim 5, wherein the anti-corrosion coating (114) is further deposited on at least part of the mold body (110) extending at the first module side (111).

7. The power module (100, 200) of claim 6, wherein the anti-corrosion coating (114) fully covers the mold body (110), the metal layer (130) and the second metal layer (120) in order to seal the power module (100) against outside humidity.

8. The power module (100, 200) according to any of the preceding claims, comprising: a sealing (141) placed between the coolant channel (143) and the second module side (112), the sealing (141) being provided to seal the coolant channel (143) against loss of coolant (145).

9. The power module (100) of any of the preceding claims, wherein the sealing (141) is configured to provide a hermetically sealing connection with the anti-corrosion coated (114) metal layer (130) and the coolant channel (143).

10. The power module (100, 200) of any of the preceding claims, wherein the sealing (141) is placed between the coolant channel (143) and the anti-corrosion coated (114) metal layer (130) or between the coolant channel (143) and a portion of the anti-corrosion coated (114) mold body (110) extending at the second module side (112).

11 . The power module (100, 200) of any of claims 5 to 7, comprising: a second sealing (241) placed between the coolant channel (143) and the first module side (111), the second sealing (241) being provided to seal the coolant channel (143) against loss of coolant (145).

12. The power module (100, 200) of claim 11 , wherein the second sealing (241) is placed between the coolant channel (143) and the anti-corrosion coated (114) second metal layer (120); or between the coolant channel (143) and a portion of the anti-corrosion coated (114) mold body (110) extending at the first module side (111).

13. A power module cooling arrangement (300, 400), comprising: a plurality of power modules (100, 200) according to any of the preceding claims which are stacked against each other by their respective first module sides (111) and second module sides (112), the coolant channels (143) of the respective power modules (100) forming a common coolant channel (243).

14. The power module cooling arrangement (300, 400) of claim 13, wherein the common coolant channel (243) extends above the first module sides (111) and the second module sides (112) of each of the plurality of power modules (100).

15. The power module cooling arrangement (300, 400) of claim 13 or 14, comprising: at least one intermediate sealing (341) being placed between a respective first module side (111) and a respective second module side (112) of two power modules (100, 200) stacked above each other, the at least one intermediate sealing (341) being configured to seal the common coolant channel (243) within the stacked power modules (100, 200) against loss of coolant (145).

16. The power module cooling arrangement (300, 400) of claim 15, wherein each intermediate sealing (341) is placed between the mold bodies (110) or between the metal layers (130, 120) of a respective first module side (111) and a respective second module side (112) of the two stacked power modules (100, 200).

17. A method (500) for producing a power module (100, 200), the method (500) comprising: molding (501) at least one semiconductor chip within a mold body (110) to form a power module (100, 200) having a first module side (111) and a second module side (112) opposing the first module side (111), the mold body (110) being arranged between the first module side (111) and the second module side (112); forming (502) a heat dissipation surface of the power module (100, 200) at the second module side (112) by a metal layer (130); depositing (503) a heat conductive anti-corrosion coating (114) on the metal layer

(130) to shield the metal layer (130) from the coolant (145) in order to prevent corrosion of the metal layer (130); and providing (504) a coolant channel (143) comprising a coolant (145) for cooling the heat dissipation surface of the power module (100, 200). 18. The method of claim 17, wherein the anti-corrosion coating (114) is deposited (503) on the metal layer (130) and/or the mold body (110) before or after the molding (501).