Power semiconductor module comprising a molded body, and method for manufacturing a power semiconductor module

Abstract

A power semiconductor module (10) is provided. The power semiconductor module (10) comprises a carrier (1), at least one module member (3), a housing frame (4) and an encapsulation body (2), the module member (3) being arranged on the carrier (1) and laterally surrounded by the housing frame (4). The housing frame (4) is arranged on the carrier (1) and protrudes vertically beyond the carrier (1) and the module member (3). The housing frame (4) has a housing frame opening (4C) in which the module member (3) is arranged, the housing frame opening (4C) being filled with the encapsulation body (2). The housing frame (4) has at least one outer side surface (4S) that is not covered by the encapsulation body (2), the encapsulation body (2) being a molding, the molding being an object made of a molding material and formed by a molding process. Furthermore, a method for manufacturing such a power semiconductor module (10) is provided.

Description

Technical Field

[0001] The present disclosure relates to a power semiconductor module including a molded body and a method for manufacturing the power semiconductor module.

Background Art

[0002] Hitherto, general industrial power electronic modules have utilized a silicone gel layer as an electrical insulator, and the silicone gel layer also acts to protect the power electronic module environmentally and mechanically. The silicone gel layer can be formed during one of the last manufacturing steps using a potting process. However, the requirements regarding the reliability and environmental robustness of power semiconductor modules are constantly increasing. Therefore, new solutions or new module concepts are needed by power module manufacturers. Alternatively, the module may have a rigid encapsulant made of a potting resin material such as an epoxy material.

[0003] Documents US 2020 / 185291 A1, US 2020 / 211921 A1, US 2019 / 318996 A1, and US 2018 / 286778 A1 describe semiconductor elements and manufacturing methods for manufacturing such elements. The element may include a resin case and a semiconductor unit installed therein. The resin case may have a frame-shaped main body and external connection terminals disposed on the frame-shaped main body. The resin case includes a storage space and a gate filled with a sealing material and sealed with the sealing material. Document US 2020 / 098701 A1 relates to a member having a housing opening filled with a sealing resin. Document DE 11 2017 008226 T5 describes a member having a case completely filled with an encapsulating material made of, for example, silicone gel or epoxy resin. This document further teaches that the case and the encapsulating material can be integrally molded using a molding resin when formed simultaneously.

Summary of the Invention

[0004] Embodiments of this disclosure relate to a mechanically stable power semiconductor module that is highly robust against environmental and external mechanical influences. Further embodiments of this disclosure relate to a simplified and efficient method for manufacturing a power semiconductor module.

[0005] Embodiments of this disclosure address, in whole or in part, the aforementioned shortcomings of the prior art. Further embodiments of power semiconductor modules and methods for manufacturing power semiconductor modules are the subject of further claims.

[0006] According to an embodiment of a power semiconductor module, the power semiconductor module comprises a carrier, at least one module member, a housing frame, and an encapsulation body, wherein the module member is placed on the carrier and surrounded laterally by the housing frame. The housing frame is placed on the carrier and protrudes vertically beyond the carrier and the module member. The housing frame has a housing frame opening in which the module member is placed, and the housing frame opening is filled with the encapsulation body. The housing frame has at least one outer side surface that is not covered by the encapsulation body. The encapsulation body is a molded body.

[0007] The vertical direction is understood to mean the direction oriented perpendicular to the main extension plane of the carrier. The transverse direction is understood to mean the direction parallel to the main extension plane of the carrier. The vertical and transverse directions are orthogonal to each other. The carrier can be a base plate or a substrate. The base plate may have an electrically conductive or electrically insulating substrate, or it may have a metal base, an insulating layer and a circuit metal coating on its upper and / or back surface. The substrate may have, for example, an electrical insulator (e.g., ceramic) and a circuit metal coating on its upper surface. A metal layer may also be formed on the back surface of the substrate. Furthermore, the substrate may be mounted on the base plate, for example by soldering.

[0008] A molded body is understood to mean an object made of a molding material. Such a molded body can be formed by a molding process, such as injection molding, transfer molding, compression molding, or film-assisted molding. The molding process can be carried out using a molding tool. A molding tool is, for example, a molding machine or part of a molding machine that can be used to provide the molding material. In general, a molded body is different from a resin body formed by a process other than the molding process, such as a potting process. The difference between a molded body and a potted resin body, or between a molded body and an object formed by a potting process, can be reflected in characteristic properties such as stiffness, material structure, or material composition. Therefore, a molded body is not a potted resin body, i.e., an object made of resin material or an object made by a potting process. Features that distinguish a molded body from a potted resin can be reflected in geometric features such as the formation of a meniscus in the molding material, which is available after the potting process rather than after the molding process. Therefore, a molded body will not have a meniscus-like geometric structure.

[0009] For example, the molding material for forming the inclusion is an electrically insulating material. The electrically insulating material may include, or be composed of, a thermosetting material or a thermoplastic material. The thermosetting material may be made based on an epoxy material. The thermoplastic material may include one or more materials from the group consisting of polyetherimide (PEI), polyethersulfone (PES), polyphenylene sulfide (PPS), or polyamideimide (PAI). The thermoplastic material can be melted by applying pressure and heat during the molding process or lamination and can be reversibly cured upon cooling and release of pressure.

[0010] The molding material may include or be composed of polymer materials. The molding material may include at least one of filled or unfilled polymer materials, for example, at least one of filled or unfilled thermoplastic materials, filled or unfilled thermosetting materials, filled or unfilled laminates, fiber-reinforced laminates, fiber-reinforced polymer laminates, and fiber-reinforced polymers laminated with filler particles.

[0011] As an example, the molded body is formed from an electrically insulating matrix material such as epoxy material. Fillers may be incorporated into the matrix material to improve the stability and robustness of the molded body. The fillers may be in the form of particles or reinforcing fibers. Furthermore, fillers may be used to adjust the coefficient of thermal expansion (CTE) or to improve the thermal conductivity of the inclusion. The fillers may have a lower or higher coefficient of thermal expansion compared to the matrix material.

[0012] Furthermore, fillers can be used to adjust the viscosity of the inclusion material during the inclusion formation process, thereby simplifying the method of applying the inclusion into the housing frame opening. For example, a molding material can be used to form an inclusion, and the molding material includes a matrix material and a filler incorporated therein to improve the viscosity of the molding material. In other words, a matrix material containing a filler may have a higher viscosity than a matrix material without a filler. This would simplify the inclusion formation process.

[0013] According to further embodiments of the power semiconductor module, the filler content of the encapsulation is at least 60 or at least 70 vol% or weight%. The filler content may be 60 to 95 vol% or weight% (including 60 vol% or weight% and 95 vol% or weight%), for example 70 to 90 vol% or weight% (including 70 vol% or weight% and 90 vol% or weight%), 70 to 85 vol% or weight% (including 70 vol% or weight% and 85 vol% or weight%), 70 to 80 vol% or weight% (including 70 vol% or weight% and 80 vol% or weight%), or 70 to 75 vol% or weight% (including 70 vol% or weight% and 75 vol% or weight%), or 60 to 75 vol% or weight% (including 60 vol% or weight% and 75 vol% or weight%). However, this disclosure is not limited to the case where the filler content of the encapsulation is at least 60 vol% or weight%. The filler content of the inclusion may be less than 60% by volume or weight, for example, 10-60% by volume or weight, or 10-50% by volume or weight, or 10-30% by volume or weight. For example, when using injection molding, the filler content may be about 10% by volume or weight.

[0014] According to a further embodiment of the power semiconductor module, the power semiconductor module comprises a plurality of module members arranged on a carrier, wherein, in a top view, the encapsulation protects the module members from environmental and external mechanical influences by, for example, completely covering the module members and filling the spaces between the module members. In the lateral direction, the encapsulation can completely surround at least one or more module members. The encapsulation is formed from an electrically insulating material. Such an insulating material may be, for example, opaque to light in the visible spectral range. However, the material of the encapsulation is not limited to an opaque material and may be radiatively transparent or partially radiatively transparent. The module members may be, but are not limited to, power semiconductor elements or substrates having mounted power semiconductor elements.

[0015] According to embodiments of the manufacturing method for a power semiconductor module, for example, described herein, the method includes the step of forming direct contact between a molding tool and the upper surface of a housing frame by applying the molding tool to the upper surface of the housing frame. For example, the upper surface of the housing frame is configured to receive the molding tool. The housing frame opening is filled with molding material to form an inclusion by a molding process using the molding tool. The housing frame has at least one outer side surface that is not covered by the molding material.

[0016] For example, at least two or three or all of the outer sides of the housing frame may not be covered by the molding material or encapsulant. Within manufacturing tolerances, the top surface of the housing frame may not be covered by the molding material or encapsulant. For example, an encapsulant formed by a molding process using a molding tool may be called a molded body. The molding process may be injection molding, transfer molding, foil-assisted molding, or other similar molding methods.

[0017] According to a further embodiment of this method, the molding material comprises a matrix material and a filler incorporated therein. For example, a matrix material containing a filler has a higher viscosity than a matrix material without a filler. The increased viscosity of the molding material allows the process of applying the molding material to module members located within housing frame openings to be carried out in a simplified and precise manner. In general, using the molding process is more effective than using the potting process, for example, when small gaps are present, because the molding process is carried out by applying pressure in a way that allows even small gaps to be properly filled.

[0018] According to a further embodiment of this method, the molding material is applied directly onto the module member, completely covering the module member in a top view. In a top view, the front side, i.e., the top side, of the power semiconductor module may be partially formed by the surface of the encapsulation. In other words, in a plan view of the power semiconductor module, the encapsulation may not be covered at all by the other layers of the power semiconductor module, or at least partially. At least in the region of the housing frame opening, the encapsulation may be the outermost layer of the power semiconductor module.

[0019] The encapsulant can partially or completely fill the housing frame opening. In a top view, the encapsulant can completely cover the bottom surface of the housing frame opening. For example, the bottom surface of the housing frame opening is configured to receive one or more modular members. In this sense, the bottom surface of the housing frame opening can be referred to as the carrier mounting area. Laterally, such a mounting area is bounded by being enclosed by the housing frame.

[0020] Forming encapsulated bodies as molded bodies improves the reliability and environmental robustness of power semiconductor modules. For example, by using molded materials with built-in fillers, the encapsulated bodies exhibit improved properties such as environmental protection, mechanical robustness, thermal expansion coefficient matching, and heat dissipation. Furthermore, using a molding process can reduce manufacturing costs in terms of raw material prices compared to potting materials.

[0021] According to this method or a further embodiment of the power semiconductor module, the upper surface of the housing frame is configured to receive a molding tool. With respect to geometric size and structure, the contact surfaces of the upper surface of the housing frame and the molding tool can be adapted to each other to achieve a tightly coordinated position of the molding tool on the upper surface, for example, an aligned position. For example, the upper surface may have one or more planar areas to allow the molding tool to be firmly connected to the upper surface of the housing frame.

[0022] This disclosure includes several aspects of power semiconductor modules and methods for manufacturing power semiconductor modules, based on their embodiments and examples. Any feature described in relation to one of these aspects is also disclosed herein in relation to other aspects, even if each feature is not explicitly mentioned in the context of a particular aspect. For example, the methods described herein are directed toward the manufacture of any of the embodiments of power semiconductor modules described herein. Thus, features and advantages described in relation to power semiconductor modules can be used in this method, and vice versa.

[0023] While various modifications and alternative forms are possible with respect to them, their specific details are shown in the drawings as examples and described in detail. However, it should be understood that the present invention is not limited to the specific embodiments and examples described herein. Rather, the present invention encompasses all modifications, equivalents, and alternatives that fall within the scope of the present disclosure as defined by the appended claims.

[0024] The attached drawings are included to provide further understanding. In the drawings, elements of the same structure and / or function may be assigned the same reference numeral. It should be understood that the examples shown in the drawings are illustrative and not necessarily to scale. [Brief explanation of the drawing]

[0025] [Figure 1A] The top view of a power semiconductor module according to one example. [Figure 1B] The cross-sectional view of a power semiconductor module during the step of applying a molding material for forming an encapsulation according to one example. [Figure 1C] The cross-sectional view of a power semiconductor module having an encapsulation according to a further example. [Figure 2] The top view of a power semiconductor module according to a further example.

Embodiments for Carrying Out the Invention

[0026] FIG. 1A is a top view of an example of a power semiconductor module 10 according to an exemplary embodiment. The power semiconductor module 10 includes a carrier 1, at least one module member 3, and a housing frame 4. The module member 3 is disposed on the carrier 1 and is surrounded laterally by the housing frame 4. The power semiconductor module 10 may include at least two module members 3 or a plurality of module members 3. The housing frame 4 is disposed on the carrier 1 and protrudes vertically beyond the carrier 1 and the module member 3. The housing frame 4 and the carrier 1 may be formed of different materials.

[0027] The carrier 1 may include a base 1G as shown, for example, in FIG. 1B. The back side of the carrier 1 or the base 1G forms the back side 10B of the power semiconductor module 10. Basically, FIG. 1B can be considered to show a cross-sectional view of the power semiconductor module 10 shown in FIG. 1A. However, in contrast to FIG. 1B, for clarity, the encapsulation 2 is not shown in FIG. 1A. The subject matter shown in FIG. 1A can also be considered as the power semiconductor module 10 in a state before the encapsulation 2 is formed.

[0028] The substrate 1G may be composed of a metal or a metal alloy. For example, the substrate 1G may be composed of Cu or Al, or a corresponding alloy. Alternatively, the substrate 1G may be composed of composite materials such as aluminum silicon carbide (AlSiC) or magnesium silicon carbide (MgSiC), or ceramic materials. However, the substrate 1G is not limited to the materials mentioned above.

[0029] In Figure 1B, the carrier 1 may be formed as a base plate. The base plate may be an integrated metal or ceramic substrate comprising a substrate 1G, an intermediate layer 1I, and / or a conductive layer 1L. The intermediate layer 1I is, for example, an electrical insulating layer.

[0030] Deviating from Figure 1B, the carrier 1 may be an insulating substrate or a conductive substrate formed as the base 1G. The component module 3 may be placed on the carrier 1. The component module 3 may comprise a component substrate, for example, a ceramic component substrate, and a semiconductor element, the component substrate may have upper and lower metal coating layers. The semiconductor element may be placed on the component substrate, for example, on the upper metal coating layer.

[0031] Deviating from Figure 1B, the substrate 1G may also be an insulating substrate. The insulating substrate may be a ceramic body or a resin insulating layer. In this case, the intermediate layer 1I may be omitted. The upper metal coating layer, which may be one of the conductive layers 1L, is placed on the upper surface of the substrate 1G. The component module 3 may be placed on the upper metal coating layer. Optionally, the back metal coating layer may be placed on the back side of the substrate 1G.

[0032] In Figure 1B, in the vertical direction, the intermediate layer 1I is positioned between the substrate 1G and the conductive layer 1L. If the substrate 1G is formed from an electrically insulating material, the conductive layer 1L can be formed directly on the substrate 1G.

[0033] The intermediate layer 1I can be an insulating layer or a connecting layer, and in the form of a connecting layer, the intermediate layer 1I is used to fix the conductive layer 1L onto the substrate 1G. One primary purpose of the intermediate layer 1I is electrical insulation. Laterally, the conductive layers 1L can be spatially separated from each other. As shown in Figure 1B, the intermediate layer 1I can be used to fix the housing frame 4 onto the carrier 1, for example, onto the substrate 1G. The intermediate layer 1I may contain an adhesive material or a resin material. The intermediate layer 1I may be used for mounting the housing frame 4. As an alternative, the housing frame 4 can be formed directly onto the carrier 1. A stable mechanical connection between the housing frame 4 and the carrier 1 can be formed during the curing process. However, other joining methods are also possible, such as using a joining material like an adhesive, or other methods such as screwing and / or applying a sealing layer.

[0034] The housing frame 4 may be made of an electrically insulating material. For example, the housing frame 4 may have a one-piece form. "One-piece housing frame" means, for example, that the housing frame 4 is made of a single part. For example, the housing frame 4 does not include separate parts connected to each other using, for example, a connecting material. More precisely, the housing frame 4 includes only one-piece parts that are connected to each other, i.e., connected without the use of further connecting materials. Such one-piece parts of the housing frame 4 may be formed from the same material. However, this disclosure is not limited to the case where the housing frame is one-piece. The housing frame may also comprise a frame portion and a cover portion, and the cover portion may be formed on or fixed to the underlying frame portion.

[0035] The housing frame 4 may be formed on the carrier 1 as a surrounding wall structure, for example, a continuous wall structure. In the lateral direction, the housing frame 4 extends along all edges of the carrier 1. In a top view, the housing frame 4 has a housing frame opening 4C. The module members 3 are arranged within the housing frame opening 4C. For example, all module members 3 of a power semiconductor module 10 are arranged within the housing frame opening 4C. The module members 3 may be electrical or electronic components. Such components may comprise one or more of the following: electronic chips, semiconductor chips, embedded semiconductor chips, substrates on which one or more chips are arranged, diodes, components containing Si and / or SiC, and discrete elements (resistors, capacitors, inductive elements, and / or transistors such as IGBTs and MOSFETs).

[0036] The housing frame opening 4C has a bottom surface 1M enclosed by the housing frame 4. The member 3 is fixed onto the bottom surface 1M. Soldering, sintering, gluing, diffusion bonding, or a transitional liquid phase bonding process can be used to fix the member 3 onto the bottom surface 1M. Thus, the bottom surface 1M of the housing frame opening 4C is configured to receive the module member 3. In this sense, the bottom surface 1M can be referred to as the mounting area for the module member 3. As shown in Figure 1B, the bottom surface 1M of the housing frame opening 4C is formed in places by surfaces of the intermediate layer 1I and / or by surfaces of the conductive layer 1L. For example, the bottom surface 1M has a plurality of separate bonding areas for receiving the module member 3, and these separate bonding areas may be, for example, spatially separated electrically conductive surfaces of the conductive layer 1L.

[0037] Outside the housing frame opening 4C, i.e., outside the housing frame 4, the carrier 1 may have at least one carrier opening 1C configured to receive screws for, for example, fixing a power semiconductor module 10 to an external carrier, such as a cooler or heat sink. Along the vertical direction, the carrier opening 1C may extend across the entire substrate 1G or across the entire carrier 1. Thus, the surface of the carrier 1 located outside the housing frame opening 4C is referred to not as a mounting area 1M for receiving module members 3, but rather as an assembly surface 1Z for fixing the carrier 1 or the power semiconductor module 10 to the external carrier.

[0038] According to Figure 1A, the carrier 1 has four carrier openings 1C located at the four corners of the carrier 1. At the corners of the carrier 1, the housing frame 4 is curved to conform to the geometric shape of the carrier openings 1C of the carrier 1. Deviating from Figure 1A, the carrier openings 1C may be formed in locations other than the corners of the carrier 1. However, the carrier openings 1C are located outside the housing frame openings 4C.

[0039] Therefore, according to at least one example of the power semiconductor module 10, the carrier 1 has at least one carrier opening 1C or two or more carrier openings 1C configured to receive at least one screw for fixing the power semiconductor module 10 to, for example, an external carrier. For example, all of the carrier openings 1C are located outside the housing frame 4.

[0040] As shown in Figure 1A, the power semiconductor module 10 includes, for example, at least one terminal 5 for electrically connecting the module member 3 to, for example, an external power supply. As shown in Figure 1B, the terminal 5 is partially integrated into the housing frame 4 and is accessible on the top surface 4A of the housing frame 4 or from outside the housing frame 4. The terminal 5 may have an external access area 5E that is accessible from the outside, and the external access area 5E of the terminal 5 is located outside the housing frame opening 4C. The external access area 5E may have, for example, through holes for receiving mounting screws used for electrical connections, such as mechanically attaching the module to busbars, cables, etc. Generally, good mechanical connections also result in good electrical connections. In a top view, the external access area 5E may be located beside the housing frame 4 and / or beside the substrate 1G of the carrier 1.

[0041] As shown in Figures 1A and 1B, the power semiconductor module 10 may have multiple such terminals 5, for example, two, four, or five or more such terminals 5. Two different terminals 5 may be assigned to different electrical polarities of the power semiconductor module 10. These two different terminals 5 may be located on opposing edge regions of the carrier 1, or on the same edge region of the carrier 1. Furthermore, control or signal terminals may be located within the module housing.

[0042] Therefore, according to at least one example of the power semiconductor module 10, the power semiconductor module 10 includes at least one terminal 5 that is partially integrated into the housing frame 4 and accessible, for example, on the upper surface 4A of the housing frame 4. The terminal 5 is accessible in an external access area 5E.

[0043] Within the housing frame opening 4C, terminal 5 may have an internal access area 5I for receiving, for example, a portion of the wiring structure 6. The wiring structure 6 may include multiple wires, such as bond wires. Through the wiring structure 6, the internal access area 5I of terminal 5 may be electrically connected to one or more conductive layers 1L and / or one or more module members 3. Furthermore, the wiring structure 6 can be used to electrically connect the conductive layers 1L to each other and / or the module members 3 to each other. Terminal 5 may be formed as a main power or auxiliary terminal that is part of the housing of the power semiconductor module 10. Terminal 5 may be electrically connected to one or more conductive layers 1L or one or more module members 3 using, for example, wire bonding or welding. However, in some cases, terminal 5 may be directly connected to the substrate by, for example, soldering or welding. Furthermore, terminal 5 may also be located on other housing components. Furthermore, terminal 5 may be a pin-shaped auxiliary or control terminal located on the side of the housing. These terminals extend vertically from the peripheral area of ​​the top surface.

[0044] The housing frame 4 has an upper surface 4A configured to receive a molding tool 9. For example, the upper surface 4A of the housing frame 4 partially forms the front side 10A, i.e., the upper side 10A, of the power semiconductor module 10. Therefore, the upper surface 4A of the housing frame 4 is freely accessible from the outside.

[0045] A portion of the upper surface 4A, for example, the contact surface 4R of the housing frame 4, is adapted to the size and / or geometric structure of the contact surface of the molding tool 9 to achieve a tightly adjusted position of the molding tool 9 on the upper surface 4A, for example, an aligned position. For example, the upper surface 4A or the contact surface 4R of surface 4A comprises one or more planar areas to allow for a close connection between the contact surface of the molding tool 9 and the upper surface 4A of the housing frame 4.

[0046] In a top view, the top surface 4A configured to receive the molding tool 9, for example, the contact surface 4R of the top surface 4A, extends between the external access area 5E and the internal access area 5I of the terminal 5, and / or between the external access area 5E and the housing frame opening. In other words, the external access area 5E and internal access area 5I of the same terminal 5 are located on different sides of the top surface 4A, or on different sides of the contact surface 4R of the top surface 4A of the housing frame 4. Therefore, the external access area 5E and internal access area 5I of the terminal 5 are not damaged when the molding tool 9 is placed on the top surface 4A. In a top view, the contact surface 4R can completely surround the housing frame opening 4C.

[0047] Normally, the orientation and position of the terminals 5 would make the molding equipment very complex in terms of forming the encapsulated body 2 as a molded body within the housing frame opening 4C. The molding process would require several additional manufacturing steps. Furthermore, it would not always be possible to meet the high-precision requirements of the molding process. However, by using a housing frame 4 having an upper surface 4A or a contact surface 4R configured to receive a molding tool 9, the molding process, which can be performed in a precise manner, would be greatly simplified.

[0048] Figure 1B shows the method steps for forming the encapsulation body 2 as a molded body. The molding tool 9 can be positioned at a predetermined location on the upper surface 4A of the housing frame 4, for example, directly on the contact surface 4R. Since only the upper surface 4A or the contact surface 4R will be fitted to the molding tool 9, a typical housing frame 4 requires only minor modifications, for example, by preparing a flat upper surface to allow for a close connection between the molding tool 9 and the housing frame 4. This solution can be applied to any type of power semiconductor module 10 where the molding process would be difficult or nearly impossible without using the housing frame 4.

[0049] As shown in Figure 1B, the housing frame opening 4C is filled with molding material to form the encapsulation body 2 using a molding process. Since the housing frame 4 is positioned on the carrier 1 and protrudes vertically beyond the carrier 1 and module member 3, only the housing frame opening 4C can be filled with molding material. The encapsulation body 2 thus formed can be referred to as a molded body. For example, at least one, at least two, or all of the outer sides 4S of the housing frame 4 are not covered by the material of the encapsulation body 2.

[0050] In one example of this method, the molding material comprises a matrix material 2M and a filler 2F incorporated therein, wherein the matrix material 2M containing the filler 2F has higher viscosity than the matrix material 2M without the filler 2F. For example, the matrix material 2M is an epoxy material. The matrix material 2M containing the filler 2F has excellent properties, for example, with respect to robustness and thermal conductivity, or with respect to the adjustment of the coefficient of thermal expansion. The filler content of the molding material or inclusion 2 may be at least 60, 65, 70, or at least 75% by volume or weight.

[0051] Therefore, according to at least one example of the power semiconductor module 10, the encapsulation body 2 comprises a matrix material 2M and a filler material 2F. For example, the filler content of the encapsulation body 2 is at least 60% by volume or weight. The filler content of the encapsulation body 2 can also be 10-60% by volume or weight, or 10-50% by volume or weight.

[0052] According to at least one example of this method, the molding material is applied directly onto the module member 3, completely covering the module member 3 in a top view. The molded body can completely cover the bottom surface 1M of the housing frame opening 4C. However, the outer side surface 4S of the housing frame 4 and / or the outer assembly surface 1Z of the housing frame opening 4C can be devoid of molding material, i.e., the material of the encapsulant 2. Since the top surface 4A of the housing frame 4 is covered by the molding tool 9 during the molding process, the top surface 4A can be devoid of molding material, i.e., the material of the encapsulant 2, at least partially or completely.

[0053] In at least one example of the power semiconductor module 10, the encapsulation body 2 is directly adjacent to the module member 3 and can completely cover the module member 3 in a top view. In a top view, the upper side 10A of the power semiconductor module 10 may be partially formed by the surface of the encapsulation body 2.

[0054] For example, the formation of the encapsulation body 2 is carried out after the module member 3 is wired, i.e., after the wiring structure 6 is formed. Therefore, the internal access area 5I of the terminal 5 located within the housing frame opening 4C can be covered at least partially or completely by the material of the encapsulation body 2. The wiring structure 6 within the housing frame opening can be covered at least partially or completely by the material of the encapsulation body 2.

[0055] In at least one example of a power semiconductor module 10, the encapsulation body 2 is located within the housing frame opening 4C or partially located on the housing frame 4 rather than outside it. For example, in a top view, the encapsulation body 2 completely covers the housing frame opening 4C. Generally, the assembly surface 1Z outside the housing frame opening 4C is not covered by the material of the encapsulation body 2.

[0056] According to at least one example of this method, the housing frame opening 4C is partially or completely filled with molding material. In a top view, the upper side 10A of the power semiconductor module 10 is partially formed by the surface of the encapsulation body 2.

[0057] Along the vertical direction, the inclusion body 2 has a vertical thickness 2T, which can be 1mm to 40mm (including 1mm and 40mm), 1mm to 20mm (including 1mm and 20mm), for example, 1mm to 15mm (including 1mm and 15mm), 1mm to 10mm (including 1mm and 10mm), or 3mm to 20mm (including 3mm and 20mm), 5mm to 20mm (including 5mm and 20mm), or 5mm to 15mm (including 5mm and 15mm). For example, the thickness 2T of the inclusion body 2 is 10mm ± 3mm.

[0058] If the housing frame opening 4C is completely filled with the molding material, the vertical thickness 2T of the encapsulation body 2 is at least as large as, or greater than, the vertical depth of the housing frame opening 4C. In the latter case, the encapsulation body 2 can protrude vertically beyond the upper surface 4A of the housing frame 4. If the housing frame opening 4C is partially filled with the molding material, the vertical thickness 2T of the encapsulation body 2 is smaller than the vertical depth of the housing frame opening 4C, for example, by 4 mm ± 2 mm. Deviating from this, it is also possible that the housing frame opening 4C of the housing frame 4 is completely filled with the molding material, in which case the vertical thickness 2T of the encapsulation body 2 is larger than the vertical depth of the housing frame opening 4C.

[0059] Figure 1C shows another example of the power semiconductor module 10 after the molding tool 9 has been removed. The power semiconductor module 10 shown in Figure 1C is essentially the same as the power semiconductor module 10 shown in Figure 1B. In contrast, the housing frame opening 4C is not completely filled by the encapsulant 2. Otherwise, all features described in relation to the power semiconductor module 10 shown in Figure 1B or Figure 1A can be applied to the power semiconductor module 10 shown in Figure 1C.

[0060] Figure 2 shows another example of the power semiconductor module 10. The power semiconductor module 10 shown in Figure 2 basically corresponds to the power semiconductor module 10 shown in Figure 1A, Figure 1B, or Figure 1C. For example, contrary to Figure 1A, the encapsulation body 2 within the housing frame opening 4C is clearly shown. Furthermore, as shown in Figure 2, the power semiconductor module 10 may include at least one module member 3 or just one module member 3. However, it is possible for the power semiconductor module 10 to have two or more module members 3. Otherwise, all features described in relation to the power semiconductor module 10 shown in Figures 1A, 1B, and 1C can be applied to the power semiconductor module 10 shown in Figure 2.

[0061] According to at least one example of the power semiconductor module 10, the upper surface 4A of the housing frame 4, for example, the contact surface 4R as part of the upper surface 4A, is configured to receive a molding tool 9. The upper surface 4A may include one or more planar areas to allow for close contact of the molding tool 9. For example, the upper surface 4A or at least the contact surface 4R is not covered by the material of the encapsulation body 2. The encapsulation body 2 may be made of an opaque material and formed, for example, not radiatively transparent to light in the visible spectral range. In deviation from this, the encapsulation body 2 may be radiatively transparent or partially radiatively transparent.

[0062] The embodiments or examples shown in the drawings above illustrate exemplary embodiments of improved power semiconductor modules or improved manufacturing methods for power semiconductor modules. Therefore, these embodiments or examples do not constitute a complete list of all embodiments or examples relating to improved power semiconductor modules or methods. Actual configurations of power semiconductor modules or methods may vary from the exemplary embodiments described above.

[0063] This application claims priority to European Patent Application EP 21 167 842.0, the disclosures of which are incorporated herein by reference. [Explanation of Symbols]

[0064] 10 Power Semiconductor Modules Top side of 10A power semiconductor module Back side of a 10B power semiconductor module 1 Carrier 1C Carrier opening of the carrier 1G support substrate 1. Intermediate layer, insulating layer, connecting layer 1M Housing frame opening bottom 1L conductive layer 1Z Assembly surface 2 Inclusions 2F Filling material for inclusions 2M encapsulation matrix material 2T Vertical thickness of the inclusion 3. Module components 4 Housing Frame 4A Top view of the housing frame 4C Housing Frame Housing Frame Opening 4S Housing Frame Outer Side 5 terminals External access area of ​​terminal 5E 5I terminal internal access area 6 Wiring structure 9. Molding Tools

Claims

1. A power semiconductor module (10) comprising a carrier (1), at least one module member (3), a housing frame (4), and an encapsulation body (2), The module member (3) is placed on the carrier (1) and is surrounded laterally by the housing frame (4). The housing frame (4) is positioned on the carrier (1) and protrudes vertically beyond the carrier (1) and the module member (3). The housing frame (4) has a housing frame opening (4C) in which the module member (3) is placed, and the housing frame opening (4C) is at least partially filled with the sealing body (2). The housing frame (4) has at least one outer side surface (4S) that is not covered by the encapsulating body (2), The aforementioned encapsulated body (2) is a molded body, and the molded body is an object made of a molding material, formed by a molding process. The power semiconductor module (10) includes at least a terminal (5) that is partially incorporated within the housing frame (4) and accessible from the outside of the housing frame opening (4C), the terminal (5) having an external access area (5E), The upper end surface of the external access area (5E) is located vertically above the upper end surface of the encapsulating body (2). The upper surface (4A) of the housing frame (4) is configured to receive the molding tool (9), In the state where the upper surface (4A) is receiving the molding tool (9), the molding tool (9) is positioned inside the external access area (5E) of the power semiconductor module (10).

2. The power semiconductor module (10) according to claim 1, wherein the upper surface (4A) of the housing frame (4) includes one or more planar regions to enable close connection to the molding tool (9).

3. The power semiconductor module (10) according to claim 1, wherein the upper surface (4A) of the housing frame (4) or at least a portion of the upper surface (4A) is not covered by the material of the encapsulation body (2).

4. The power semiconductor module (10) according to any one of claims 1 to 3, wherein the carrier (1) is a base plate or includes an insulating substrate.

5. The power semiconductor module (10) according to any one of claims 1 to 3, wherein the encapsulation body (2) comprises a matrix material (2M) and a filler (2F).

6. The power semiconductor module (10) according to claim 5, wherein the filler content of the encapsulated body (2) is at least 60% by volume or by weight.

7. The power semiconductor module (10) according to claim 5, wherein the filler content of the encapsulated body (2) is 10 to 60% by volume or by weight.

8. The power semiconductor module (10) according to any one of claims 1 to 3, wherein the encapsulated body (2) is located only within the housing frame opening (4C), or is located within the housing frame opening (4C) but not outside the housing frame (4) and is partially located on the housing frame (4).

9. The power semiconductor module (10) according to any one of claims 1 to 3, wherein the external access area (5E) is accessible from the outside, is located outside the housing frame opening (4C), and has through holes for receiving electrical connections.

10. The power semiconductor module (10) according to any one of claims 1 to 3, wherein the carrier (1) has at least one carrier opening (1C) configured to receive screws for fixing the power semiconductor module (10) onto an external carrier, and the at least one carrier opening (1C) is located outside the housing frame (4).

11. The encapsulating body (2) is directly adjacent to the module member (3) and completely covers the module member (3) when viewed from above. In a top view, the upper side (10A) of the power semiconductor module (10) is partially formed by the surface of the encapsulation body (2), as described in any one of claims 1 to 3.

12. A method for manufacturing a power semiconductor module (10) comprising a carrier (1), at least one module member (3), a housing frame (4), and an encapsulation body (2), The module member (3) is placed on the carrier (1) and is surrounded laterally by the housing frame (4). The housing frame (4) is positioned on the carrier (1) and protrudes vertically beyond the carrier (1) and the module member (3). The housing frame (4) has a housing frame opening (4C) in which the module member (3) is arranged. The power semiconductor module (10) includes at least a terminal (5) that is partially incorporated within the housing frame (4) and accessible from the outside of the housing frame opening (4C), the terminal (5) having an external access area (5E), The upper end surface of the external access area (5E) is located vertically above the upper end surface of the encapsulating body (2). The upper surface (4A) of the housing frame (4) is configured to receive the molding tool (9), With the upper surface (4A) receiving the molding tool (9), the molding tool (9) is positioned inside the external access area (5E). The aforementioned method, The steps include applying the molding tool (9) to the upper surface (4A) of the housing frame (4) to form direct contact between the molding tool (9) and the upper surface (4A) of the housing frame (4), A method comprising the steps of filling the housing frame opening (4C) with molding material (2M, 2F) to form an inclusion (2) by a molding process using the molding tool (9), wherein the housing frame (4) has at least one outer side surface (4S) that is not covered by the molding material (2M, 2F), and the molding process is injection molding, transfer molding, compression molding, or a film-assisted molding process.

13. The method according to claim 12, wherein the molding material (2M, 2F) comprises a matrix material (2M) and a filler (2F) incorporated therein, and the matrix material (2M) containing the filler (2F) has a higher viscosity than the matrix material (2M) without the filler (2F).

14. The molding material (2M, 2F) is applied directly onto the module member (3), completely covering the module member (3) in a top view. The method according to claim 12 or 13, wherein, in a top view, the upper side (10A) of the power semiconductor module (10) is partially formed by the surface of the encapsulation body (2).

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