Power semiconductor module and method for manufacturing a power semiconductor module

Abstract

The present invention relates to a power semiconductor module (1), the power semiconductor module (1) comprising a module housing (50) having an alignment element (52), and a substrate structure (10) which is plate-shaped and has an upper side (12), an upper metallized layer (30) disposed on the upper side, a power semiconductor element (18) disposed on the upper side (12) and electrically connected to the upper metallized layer (30), and a concave feature (20) disposed on the upper side (12), wherein the substrate structure (10) is fastened to the module housing (50) to house the power semiconductor element (18), and the alignment element (52) penetrates into and / or through the concave feature (20) from the upper side (12), thereby providing a mechanical engagement between the module housing (50) and the substrate structure (10) with respect to movement in at least one direction in a plane (P) along the upper side (12).

Description

Technical Field

[0001] Technical Field The present invention relates to a power semiconductor module. The power semiconductor module includes a module housing and a substrate structure that is plate-shaped and has an upper side, an upper metallization layer, and a power semiconductor element. The substrate structure is fastened to the module housing, and the power semiconductor element is electrically connected to the upper metallization layer. The present invention also relates to a method for manufacturing a power semiconductor module.

Background Art

[0002] Background Art The substrate structure of a power semiconductor module is typically plate-shaped, and the outer edge of the substrate structure is used to position the module housing relative to the substrate structure by a fitting portion that extends away from the surface of the module housing and abuts against the upper side of the substrate structure. The fitting portion fits into the outer edge and realizes positioning substantially parallel to the substrate structure. The fitting portion may be formed as a snap-fit portion in order to realize a mechanical connection perpendicular to the substrate structure by, for example, a snap mechanism.

[0003] Such an alignment structure, for example, a fitting portion, is typically a protruding structure on the bottom surface of a housing frame that extends downward and at least partially contacts the outer edge of the base plate.

[0004] The manufacturing processes for the base plate and the module housing in which the outer edge is used for the above positioning are complicated. For example, the substrate structure may have geometric features such as recesses on its outer edge. The substrate structure may have a shape deviating from a simple rectangular shape (for example, a dog-bone shape). This requires separate machining steps or more complex molding tools, and the available area of the power module is reduced. Such geometric features reduce the heat dissipation capacity of the substrate structure. In addition, the manufacturing of a module housing having a fitting portion, for example, a snap-fit portion, or other alignment structure is costly. [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] Summary of the Invention Therefore, an object of the present invention is to provide a power module and a method for manufacturing the same that improves the positioning of the substrate structure relative to the module housing, particularly at low cost. In particular, an object is to avoid or mitigate the shortcomings of known solutions. [Means for solving the problem]

[0006] The object of the present invention is resolved by the features of the independent claim. Preferred implementations are described in detail in the dependent claims.

[0007] Therefore, the above objective is particularly addressed by a power semiconductor module, which is a power semiconductor module. A modular housing having alignment elements, The substrate structure comprises a plate-shaped substrate structure, the substrate structure having an upper side, an upper metallized layer disposed on / on the upper side of the upper side, a power semiconductor element disposed on the upper metallized layer, which is particularly fastened, particularly electrically connected, for example, soldered on / on the upper side of the substrate structure, and a particularly formed concave feature disposed on the upper side, the substrate structure being fastened to a module housing to accommodate the power semiconductor element, The alignment element is positioned to penetrate and / or pass through the concave feature from the upper side, and / or penetrate and / or pass through the concave feature from the upper side, thereby providing a mechanical engagement between the module housing and the substrate structure, particularly positive mechanical engagement and / or secure fit and / or shape fit, with respect to movement in a plane at least along the upper side, in particular, with respect to at least one direction, or oblique to each other, and / or multiple directions contained in the plane.

[0008] The above objective is further solved by a power semiconductor module or a method for manufacturing such a power semiconductor module, the method comprising a module housing having alignment elements and a plate-shaped substrate structure, the substrate structure having an upper side, an upper metallized layer disposed on the upper side of the substrate structure, power semiconductor elements disposed on the upper metallized layer, particularly fastened, particularly electrically connected, for example, soldered to the upper side of the substrate structure, and a particularly formed concave feature disposed on the upper side, the module housing being designed to accommodate the power semiconductor elements, and the method is, - The method includes the step of positioning the module housing on the upper side, wherein the alignment element penetrates a concave feature from the upper side to position the module housing relative to the substrate structure along a plane along the upper side, and this method further, - Includes the step of fastening the substrate structure to the module housing by joining and / or screwing.

[0009] The proposed solution is based on the idea that positioning between the substrate structure and the module housing can be achieved by a concave feature in the substrate structure that can be penetrated by the alignment element of the module housing. This idea essentially implies that the concave feature is intended to be penetrated. This could mean that the concave feature is located in one of the central locations of the substrate structure as a blind hole or pocket that can fix the alignment element in at least one direction, in multiple diagonally aligned directions in the plane, or in all directions parallel to the substrate structure / plane. It is particularly preferable that the concave feature (for the alignment element) is formed by a separation groove between / inside the metallization pattern of the upper metallization layer. In particular, the concave feature cannot be located on or around the outer edge of the substrate structure in order to allow penetration into / through the concave feature. Another option is that the concave feature is located laterally away from the power semiconductor element so that it can be accommodated even when the module housing is closed, for example.

[0010] In particular, the present invention allows for easy positioning of a typical, and especially partially and / or at least substantially, plate-shaped, substrate structure having at least one power semiconductor element relative to the module housing when attaching the module housing to the substrate structure. For example, alignment elements protruding into the module housing engage with a concave feature of the substrate structure, achieving positioning in a direction parallel to the extended portion of the substrate structure. The concave feature is positioned such that all sides are surrounded by the outer edge of the plate-shaped substrate structure so that it is housed in and / or covered by the module housing. In other words, the concave feature is substantially located anywhere on the upper surface of the substrate structure and / or not located on the outer edge of the substrate structure.

[0011] In particular, the upper metallized layer may form a concave feature. Specifically, the concave feature in the sense of the present invention does not have to be formed on the power semiconductor device, such as the chip, and / or on the base plate. Alternatively, the concave feature may be formed on the power semiconductor device.

[0012] The idea of ​​the present invention is that, in particular, topography of one side (e.g., the upper side) of the substrate structure, especially topography for the electrical interconnection of power semiconductor elements, is used to position the module housing relative to the substrate structure.

[0013] This invention provides a solution that enables extremely precise positioning between the module housing and the substrate structure, allowing power semiconductor elements to be housed and electrically used while keeping the risk of defective products extremely low.

[0014] The present invention, and the aspects described herein, provide an improved power semiconductor module that is easier to manufacture.

[0015] Further advantageous realizations of the present invention are shown below. The named features in the realizations may be considered individually in combination with each other or individually. Features may be considered in methods and / or power semiconductor modules.

[0016] Power semiconductor modules are intended to be, for example, in-vehicle power modules used in hybrid or plug-in electric vehicles, or in trains such as commuter trains, to convert direct current from a battery into alternating current for electric motors.

[0017] The module housing may have at least substantially an interior for housing power semiconductor elements. The module housing may have at least one side wall and / or top cover. The top cover is intended to be located on the opposite side of the substrate structure. Thereafter, a closable space for the upper side and / or power semiconductor elements may be provided. When the substrate structure is placed and / or fastened to the module housing with its upper side facing the module housing, the power semiconductor elements can be housed, specifically located and / or protected within the module housing.

[0018] The module housing may, in particular, serve to accommodate alignment elements. The alignment elements may face and / or be in contact with the upper metallized layer, and may be coupled to the module housing on the opposite side of the substrate structure for positioning purposes; “coupled” may include being formed integrally with the module housing or being connected to the housing as a separate part. The alignment elements may not particularly face and / or be in contact with the outer edge of the substrate structure, but rather may be located particularly within the module housing.

[0019] Plate-like means that the shape is flat and extends at least substantially in two of the three dimensions. The plate may be flat in one direction, or substantially elongated in two directions, and all three directions are perpendicular to each other. In particular, for a plate to be considered plate-like, each of the width and length of the plate is at least 2, 5, 10, 50, 100 or more times greater than the thickness. Plate-like structures may still contain non-planar topography on the top and / or bottom sides of the substrate structure, for example, on the side containing power semiconductor elements, insulating grooves, chips, wires, etc.

[0020] A substrate structure is understood to be plate-like if a typically substantial portion of the substrate structure, such as the base plate / bottom plate or the insulating layer, is plate-like. The substantial portion is preferably considered to constitute at least 10% of the weight and / or volume of the substrate structure, and this typically applies to one or both of the base plate / bottom plate and the insulating layer. In particular, it is most preferable that the insulating layer and / or the bottom plate are plate-like, and / or at least substantially plate-like.

[0021] Furthermore, the metallized layer and / or metallized pattern may be considered to be plate-like. "Penetrating" means that the alignment element enters / through the substrate structure, enters / passes through the substrate structure, and / or penetrates the substrate structure. The alignment element is substantially understood to be located inside the substrate structure, and / or within the substrate structure, and / or at least partially at any location in the center of the substrate structure, and / or at any location on the top surface of the substrate structure. Penetration is particularly insufficient if, for example, it merely faces the substrate structure at its outer edge, and / or merely touches the substrate structure. In particular, the substrate structure must surround the alignment element, particularly at least partially, and / or from one, two or more sides. In particular, penetration may include the alignment element being in contact with the substrate structure.

[0022] The plane extends substantially along the upper side of the substrate structure and / or along the dominant extension. For example, the plane extends parallel to those of the substrate structure in any layer, such as a metallization layer, an insulating layer, and / or in any plate, such as a bottom plate / base plate / bottom metal plate.

[0023] The upper side may not have a completely flat surface and, in particular, exhibits a specific topography due to, for example, insulating grooves, power conductor elements, and / or other features. The upper side is associated with substantially one side of the substrate structure, including, for example, the upper metallization layer and the chip, and the bottom side is associated with substantially another side of the substrate structure, for example, for the arrangement of the entire power semiconductor module, for example, for heat transfer.

[0024] In a first preferred embodiment, the substrate structure has an insulating layer having an upper metallized layer and optionally a bottom metallized layer on the opposite side of the upper metallized layer. The insulating layer may comprise a ceramic material and / or resin sheet typically filled with inorganic particles or fibers for electrical insulation. The insulating layer is typically a dielectric layer made of, for example, a flexible material or a solid material. The upper metallized layer and / or bottom metallized layer particularly contain or consist of copper. The substrate structure may have an insulating layer having an upper metallized layer on the upper side of the substrate structure and a bottom metallized layer on the bottom side. The insulating layer may be a ceramic layer containing, for example, at least one type of ceramic and / or oxide, such as aluminum oxide. The upper metallized layer and / or bottom metallized layer may be layers attached to and / or coated on the insulating layer. The insulating layer and the metallized layer may be attached to each other, for example, to form a structural unit. At least one or both of the metallized layers contain copper, aluminum, or an alloy thereof. One or both of the metallized layers may be directly coated and / or formed on the insulating layer. The insulating layer may provide structural integrity to the substrate structure, the upper metallized layer may provide at least electrical interconnection of power semiconductor elements, and / or the bottom metallized layer may provide thermal radiation or heat dissipation means. In some specific power semiconductor module designs, the bottom metallized layer may provide electrical interconnection.

[0025] The upper and / or lower metallized layers may contain, or may contain, copper and / or aluminum or corresponding alloys. The upper and / or lower metallized layers may have a coating, such as a nickel coating, for improved corrosion resistance, improved electrical properties, improved bonding properties, and / or cost reduction.

[0026] In another implementation example, the substrate structure has a bottom plate on the bottom side opposite to the upper side. Optionally, the bottom plate is coupled (e.g., directly or indirectly) to an insulating layer, preferably (indirectly) via a bottom metallization layer and / or (directly) sandwiching the bottom metallization layer. Optionally, the bottom plate includes a metal or a metal composite material, such as AlSiC, MgSiC, aluminum, copper, steel, and / or other metals or alloys. In particular, the bottom plate may include metals within the alloy and / or within the composite material, particularly AlSiC and / or MgSiC.

[0027] The bottom plate is understood or may generally be referred to as a base plate or a heat sink, for example, to serve as a base of a power semiconductor module. The bottom plate is typically distinguished from a layer (e.g., metallization and / or insulation), especially by its thickness preferably being more than 2 mm or 3 mm and / or less than 6 mm or 5 mm, and the layer typically exhibits a smaller thickness than that. The bottom plate is distinguished from a layer (e.g., metallization and / or insulation), especially by its material preferably including more than 2 wt% of aluminum, steel, carbon, silicon, and / or other materials, and the layer may exhibit different materials. The bottom plate may be made of the same material as the bottom metallization layer. There is also the option that the bottom plate is made of a different material from the bottom metallization layer. The bottom plate may exhibit a plate-like shape in that it has a solid and flat structure extending substantially in-plane / along the plane. For example, the bottom plate may include arcuate portions, ridges, and / or recesses, but is substantially plate-like.

[0028] The base plate and / or bottom plate may be soldered and / or bonded and / or bonded to the insulating layer, preferably via a bottom metallized layer. Thus, the substrate structure may comprise an insulating layer having an upper metallized layer on the upper side of the substrate structure and a bottom plate on the lower side. The insulating layer may be directly bonded and / or laminated onto the bottom plate to provide an insulating substrate, in particular an insulating metal substrate. The insulating layer may be a polymer layer, for example, comprising at least one polymer, in particular a polymer compound, resin, polymer compound layer, resin layer and / or resin sheet, typically filled with inorganic particles or fibers. The bottom plate may provide a function for attachment to thermal radiation means or heat dissipation means and, for example, cooling means.

[0029] A bottom metallized layer and / or bottom plate can be provided on the underside of the substrate structure, particularly to thermally connect the substrate structure to the cooler.

[0030] Power semiconductor elements may be electrically connected to the upper metallized layer. At least one contact area may be provided for external contact with the power semiconductor module, particularly the power semiconductor elements, by one or more terminals or connectors, such as terminal pads. The terminals or connectors may be metallized areas that can be used for mounting external terminals, and such patterns may be electrically connected to the power semiconductor elements. The upper metallized layer may have one or more power semiconductor elements and may further comprise one or more contact areas.

[0031] The upper metallized layer may provide multiple patterns for mounting power semiconductor elements and / or other electronic elements such as sensors, control elements and / or passive elements, and / or for main terminals and auxiliary terminals, in particular for external terminals for external connections. Patterns in the upper metallized layer for terminal mounting may be electrically connected to power semiconductor elements or other elements, or to other patterns in the upper metallized layer.

[0032] Power semiconductor elements may be in the form of chips. Multiple power semiconductor elements may be provided within a power semiconductor module. The power semiconductor elements may include one or more transistors and / or switching elements, such as insulated gate bipolar transistors (IGBTs), metal-oxide-semiconductor field-effect transistors (MOSFETs), diodes, and / or others.

[0033] Power semiconductor elements can be mounted on the same substrate structure for the module housing, or on several substrate structures, for example, on one substrate structure and on another. It is also possible to mount them, for example, on a common base plate, with a bottom metallized layer, an insulating layer, and an upper metallized layer, or several configurations comprising these.

[0034] All power semiconductor elements may be of the same type, or there may be at least two different types of power semiconductor elements, such as diodes and / or transistors. Power semiconductor elements may include or be selected from the group consisting of metal-oxide-semiconductor field-effect transistors (MOSFETs), metal-insulating semiconductor field-effect transistors (MISFETs), insulated-gate bipolar transistors (IGBTs), bipolar junction transistors (BJTs), gate turn-off thyristors (GTOs), gate commutation thyristors (GCTs), junction-gate field-effect transistors (JFETs), high electron-mobility transistors (HEMTs), and diodes. If there are multiple power semiconductor elements, all power semiconductor elements may be of the same type, or there may be power semiconductor elements of different types.

[0035] The term "power semiconductor module" means, for example, that the module is configured for high current. For instance, a power semiconductor module is configured to handle currents of at least 10A, at least 50A, at least 100A, or at least 500A. Correspondingly, a power semiconductor element may be a high-power element, particularly a high-power chip.

[0036] The metallized layer may be in direct contact with the insulating layer. The insulating layer may be the only layer between the upper metallized layer and the lower metallized layer and / or the bottom plate. The insulating layer may be the only layer between the upper metallized layer and the bottom plate.

[0037] The insulating layer may comprise one or more ceramic layers. For example, the ceramic layers may comprise a resin material filled with particles or fibers of AlN, Si3Ni, Al2O3, BN, or an inorganic material. The insulating layer may comprise, or consist of, at least one insulating resin sheet. The insulating layer may be filled with an inorganic filler, such as inorganic particles. At least one inorganic filler may be a ceramic material such as AlN, Al2O3, Si3N4, or BN.

[0038] The substrate structure provides an electrical contact platform for one, some, or all of the power semiconductor elements.

[0039] In another preferred implementation, the substrate structure is fastened to the module housing, preferably by contact surfaces or at least one section thereof, and / or the contact surfaces are in direct contact with the module housing. The contact surfaces are, in particular, part of any layers such as a bottom plate and / or an insulating layer, and / or formed together with them. The contact surfaces are typically circumferentially located with respect to the upper metallized layer, primarily / substantially. Alternatively or in addition to this, the module housing may have contact surfaces, in particular, the contact surfaces of the module housing and the substrate structure corresponding to each other. Fastening may be achieved, for example, by bonding using adhesives, and / or by screwing, for example, screws being screwed into the module housing, and / or by clamping, for example, by clamps that hold the module housing and / or the substrate structure. Bonding may be achieved by particularly circumferential and / or annular contact surfaces of the module housing that abut the (as described above) contact surfaces of the substrate structure on the upper side, in particular contact surfaces surrounding power semiconductor elements and / or alignment elements. The contact surfaces may be located on one side of the module housing and / or on the front of the side wall of the housing and / or on the opposite side of the upper cover of the module housing intended to face the substrate structure. The contact surfaces may be located in a contact plane that limits the extension of the module housing, including an alignment element, particularly on one side of the module housing. Threading may be achieved by screws threaded from the bottom and / or top sides, particularly perpendicular to the plane, particularly through the plane. To connect the entire substrate structure to the housing, the substrate structure, such as a bottom plate, can be threaded into the module housing from the bottom side opposite the top side. Screws can also be threaded from the top side through the module housing into the substrate structure. Threads or threaded nuts / structures may be located within the substrate structure and / or module housing for threading. However, self-cutting screws may be used for threading.

[0040] In another preferred implementation, the upper metallized layer has a thickness of at least 0.25 mm, 0.5 mm, 0.75 mm, 1 mm or more. The thickness of the upper metallized layer may be up to 5 mm, 4 mm, 3 mm, 2 mm or less. The upper metallized layer may be deposited in a coating process, a lamination process, and / or a brazing process. The thickness may be the nominal thickness of the metallized layer as considered immediately after the (raw) production of the metallized layer.

[0041] In another preferred implementation, the upper metallized layer has isolation grooves to form individual conductive sections and / or at least one electrical circuit of the upper metallized layer, which are in particular at least substantially the same thickness. Multiple isolation grooves may be provided. The isolation grooves and / or individual conductive sections may be understood as topography of the substrate structure and thus may be at least partially derived from concave features. Preferably, power semiconductor elements are located above the upper metallized layer, particularly in contact with the upper metallized layer, in particular in individual electrical connections to the conductive sections. Another substrate structure may be provided on the upper metallized layer, for example, this other substrate structure may be at least substantially smaller than the above substrate structure. This other substrate may be an auxiliary substrate on which gate resistors or control elements are located. Optionally, main terminals and / or auxiliary terminals may be located on the upper metallized layer. Thus, the upper metallized layer can be provided to form electrical circuits by providing each conductor formed, for example, by topography and / or shape along the upper side of the upper metallized layer itself.

[0042] Multiple concave features may be provided. Multiple alignment elements may be provided. Multiple concave features or concave features may correspond to multiple alignment elements or alignment elements. The concave features may be arranged at a distance from each other along a plane. The alignment elements may be arranged at a distance from each other along a plane.

[0043] The isolation groove may at least partially form a concave feature or a plurality of concave features for one or more alignment elements. In particular, the isolation groove may have a depth of 0.25 mm, 0.5 mm or more for good stability. The concave features may be integrated into the substrate structure to synergistically use the isolation groove for both electrical isolation and positioning of the module housing. When the alignment element penetrates the isolation groove in this manner, the possibility of creep current through the isolation groove is further reduced. At the position of the alignment element, the creep distance is even beneficially blocked.

[0044] In another preferred implementation, the concave feature is partially or completely surrounded by the upper metallized layer, particularly within the upper metallized layer, to a radial size of at least 1 mm, starting from the boundary of the concave feature. The concave feature may be a localized reduction in the thickness of the upper metallized layer, e.g., a blind hole and / or recess. The concave feature may be a bore and / or hole penetrating the metallized layer. The concave feature may be completely or at least partially surrounded by the metallized layer. Thus, the mechanical stability of the concave feature is increased. The concave feature may be provided and / or formed directly by the metallized layer, and / or manufactured together with it.

[0045] The alignment element may be in the form of a projection, for example, projecting obliquely and / or perpendicularly to a plane, particularly from the module housing. The alignment element may project and / or extend and / or be located inside the module housing. The alignment element may be in the form of a pin.

[0046] In another preferred implementation, the alignment element penetrates and / or passes through the upper metallized layer, in particular. The alignment element preferably penetrates and / or passes through the insulating layer, such as a resin sheet and / or ceramic material, in particular. The alignment element may preferably penetrate and / or pass through the bottom metallized layer and / or bottom plate. The recessed feature may be a blind hole that begins on the upper side and ends at any location in the substrate structure, such as the upper metallized layer, the insulating layer and / or the bottom metallized layer and / or bottom plate. The recessed feature may be a hole that passes through the substrate structure, for example, that begins on the upper side and ends on the opposite side, i.e., the bottom side.

[0047] In another preferred implementation, the front of the alignment element is positioned at a distance from the substrate structure or in contact with the substrate structure, particularly in a direction perpendicular to the plane. The alignment element may be positioned at a distance from the substrate structure, e.g., a minimum distance, or in contact with the substrate structure, particularly when assembling power semiconductor modules, to provide a gap. Thus, the alignment element may stop in a specific movement path perpendicular and / or oblique to the plane. The alignment element may simply protrude into a concave feature without stopping.

[0048] The front portion of the alignment element, for example, the side facing the substrate structure, may be designed to contact the substrate structure on at least one side of the front portion. The alignment element may also serve to make contact on at least one side, for example, its tip and / or one side of the front portion, for positioning purposes. The alignment element may also be in circumferential contact, for example, partially or completely, with the concave feature, i.e., the geometric shape of the substrate structure that defines the extent of the concave feature. The front portion can be understood as the front portion of the alignment element and / or its front surface.

[0049] In another preferred implementation, the alignment element is formed integrally with the module housing and / or made of the same material as the module housing. To be integral, the alignment element may be joined in / to the module housing and / or formed integrally with it. In particular, if the module housing is made of a fiber-reinforced polymer compound, for example, if it is manufactured by injection molding or transfer molding, the alignment element may be formed together with the manufacture of the entire module housing. The alignment element may be manufactured together with the module housing by injection molding and / or transfer molding.

[0050] In another preferred implementation, the alignment element is formed separately from the module housing and / or made of a different material from the module housing. In particular, the alignment element may be made of metal (for example, when the concave feature is electrically insulated and / or located at a distance from the electrical circuit, and / or when the alignment element is inserted into a concave feature that is not part of the isolation groove and mounted in the isolation housing), and / or made of a polymer compound. The alignment element may be attached to the module housing. The alignment element may be a separate component from both the substrate structure and the module housing, and / or may be positioned between the module housing and the substrate structure.

[0051] In another preferred implementation, the alignment element has a circular, polygonal, triangular, rectangular, square, and / or prismatic shape in cross-sectional view. This shape may be present at least at its front portion, or at least 10%, 25%, 50%, or 75% of its length as considered perpendicular to the plane. This shape may be fitted into an insulating groove and / or other available recess in the substrate structure. The insulating groove may have a shape that at least partially corresponds to the shape of the alignment element, particularly the shape of the front portion of the alignment element.

[0052] The front portion of the alignment element may be at least substantially flat and / or extend at least substantially parallel to the plane. The alignment element may have an elongated shape at least substantially perpendicular to the plane.

[0053] In another preferred implementation, the alignment element and / or concave feature have a size / diameter of at least 0.7 mm along and / or parallel to the plane. This is beneficial for mechanical stability and positioning accuracy.

[0054] The alignment element may have a length of at least 1.0 mm and may, for example, protrude from the upper cover of the module housing toward the substrate structure and / or be located between the side walls of the module housing and / or be located inside the module housing.

[0055] Alignment elements, particularly their front / tip and / or periphery, may be molded to correspond to the upper separation pattern and / or separation groove and / or bottom metallized layer. Separation grooves or a plurality of separation grooves may form the separation pattern.

[0056] With particular consideration given to directions parallel to the plane, and more specifically to directions including alignment elements that should contact concave features for positioning, the alignment elements and concave features may exhibit at least substantially the same size in the plane, for example, within ±1%, ±2.5%, ±5%, or ±10%. This size can be considered as the radial size. This allows for easy positioning within tolerances on the one hand, and provides a highly reliable positioning means on the other hand.

[0057] In another preferred implementation, the outer edge of the substrate structure is not in contact with the module housing, for example, its mating portion, and in particular the mating portion has a snap-fit ​​feature and / or is in the form of a snap-fit ​​portion. The substrate structure does not have to be covered in the side view. In particular the module housing, for example its mating portion or protruding edge, does not cover the substrate structure and / or is not in contact with it in the side view. In particular the substrate structure is not covered on all sides and / or is not considered from multiple or all possible side views. In particular the module housing is omitted if it has elements that protrude further than the surface in contact with the substrate structure, such as mating portions, in particular mating portions for gripping and / or covering the outer edge of the substrate structure. No part or section of the module housing has to be designed to extend beyond the outer edge of the substrate structure, except particularly for positioning purposes.

[0058] In another preferred implementation, the substrate structure is fastened, for example, by bonding using adhesive and / or by screwing, for example, screws into the module housing, and during fastening, for example, during the application or curing of adhesive and / or screwing in of screws, the alignment element penetrates the concave feature and plays a role in positioning the module housing along the plane relative to the substrate structure.

[0059] In another preferred implementation, the alignment element acts as a support configured to support the upper cover of the module housing relative to the substrate structure. Thus, the alignment element may be in contact with and / or bonded to the upper cover on one side, particularly in a direction oblique or perpendicular to the plane, and may be in contact with and / or bonded to the substrate structure on the opposite side. This improves the overall mechanical stability of the power semiconductor module and may allow for cost reductions through the possibility of rebuilding the module housing. Therefore, the alignment element can provide both alignment and support functions. The alignment element provides improved stability.

[0060] These and other aspects of the present invention will become apparent from the examples described below and will be explained with reference to those examples. [Brief explanation of the drawing]

[0061] [Figure 1] This is a schematic cross-sectional view of a power semiconductor module in which an alignment element penetrates a concave feature. [Figure 2] This is a schematic cross-sectional view of a power semiconductor module in which an alignment element penetrates a concave feature. [Figure 3] This is a schematic cross-sectional view of a power semiconductor module having a substrate structure and an upper power semiconductor element, wherein alignment elements provide secure mating of the module housing to the substrate structure. [Figure 4] This is a perspective view of a power semiconductor module. [Modes for carrying out the invention]

[0062] Explanation of implementation examples This description includes procedural or methodological aspects in describing the structural features of power semiconductor modules, and the structural features can be fully understood in this manner. It is emphasized to the reader that such structural features can be actively or, without the problem of intermediate generalization, extracted from the context described to form aspects of the invention. It is also emphasized to the reader that each of the structural features described below, while potentially extracted from the context, can be understood as an individual aspect of the invention to distinguish it from known solutions.

[0063] In Figures 1 and 2, a power semiconductor module 1 is shown comprising a module housing 50 having alignment elements 52 and a plate-shaped substrate structure 10. The upper surface of the substrate structure 10 defines a plane P at least substantially.

[0064] The power semiconductor module 1, particularly its substrate structure 10, has power semiconductor elements 18 in the form of chips, which are not visible in the parts shown in Figure 1 or Figure 2. The power semiconductor elements 18 are located and mounted on the upper side 12 and electrically connected to it. The opposite side of the upper side 12 is the bottom side 14.

[0065] In both Figure 1 and Figure 2, the substrate structure 10 is fastened to the module housing 50 by screws and / or joints (or vice versa). The fastening is substantially provided to the upper side 12 of the substrate structure 10, particularly the sides and / or near the outer edge. This accommodates the upper side 12 at least substantially, in particular the semiconductor element 18.

[0066] In both Figure 1 and Figure 2, the alignment element 52 plays a role in positioning the module housing 50 relative to the substrate structure 10 along the plane P by mechanical engagement and / or secure fitting. In the configuration shown, the alignment element 52 stops within the concave feature 20 as it moves laterally along the plane P.

[0067] The alignment element 52 can move toward and from the planes of Figures 1 and 2, i.e., obliquely, vertically, or perpendicularly to plane P. In this case, as shown in the figure, the concave feature 20 is formed by an insulating groove 24 extending in the above direction. In particular, the alignment element 52 may be movable along the extension of the insulating groove 24 along plane P, and the alignment element 52 may have a proposed mechanical engagement obliquely to the extension, for example, in the left or right direction in Figures 1 and 2.

[0068] In Figure 1, the alignment element 52 is formed separately from the module housing 50 and is removably connected to the module housing 50. The alignment element 52 and the module housing 50 are each composed of at least one polymer compound, for example, the same or different polymer compounds.

[0069] In Figure 2, the alignment element 52 is formed integrally with the module housing 50. Both the alignment element 52 and the module housing 50 are made of a specific polymer compound as injection molded products.

[0070] In both Figure 1 and Figure 2, the substrate structure 10 has an upper metallized layer 30 containing copper, an insulating layer 32 made of an insulating material (such as a ceramic material, a resin sheet, or a polymer compound), and a bottom metallized layer 34 on the opposite side of the upper metallized layer 30 containing copper. Layers 30 and 34 are laminated, bonded, or coated on both sides of the insulating layer 32 and are therefore mechanically bonded to it.

[0071] In Figure 1, the substrate structure 10 has a concave feature 20 formed only on the upper metallized layer 30, the concave feature 20 extending in the direction of depth 22 along its thickness 31 of at least 0.5 mm through the upper metallized layer 30, and having a size 21 as a diameter 5% to 10% larger than the size 52 as the diameter of the alignment element 52 that protrudes on and / or toward the upper side 12. The length 56 of the alignment element 52 is at least 1 mm.

[0072] In Figure 2, the substrate structure 10 has a concave feature 20 formed thereon that extends through the entire substrate structure 10 in the direction of depth 22. The concave feature 20 extends in the depth direction through layers 30, 32, and 34 having thicknesses 31, 33, and 35. The concave feature 20 has a diameter size 21 which is at least substantially the same as the diameter size 53 of the alignment element 52 that protrudes from and / or toward the upper side 12. In particular, the length of the concave feature 20, especially oblique or perpendicular to the plane P, is at least 1% greater than that of the alignment element 52. The length 56 of the alignment element 52 is at least 1 mm.

[0073] In both Figure 1 and Figure 2, the alignment element 52 penetrates the concave feature 20, but in Figure 2, the alignment element 52 also penetrates the concave feature 20, and therefore essentially penetrates the substrate structure 10.

[0074] In Figure 1, the front portion 54 of the alignment element 52 is not in contact with the bottom of the recessed feature 20 and / or is positioned at a distance from the substrate structure 20, for example, from the bottom of the recessed feature 20, however, if the module housing 50 is further pushed toward the substrate structure 10, the alignment element 52 may come into contact with the bottom of the recessed feature 20. Optionally, the recessed feature 20 is in the form of a bore and / or a blind hole and / or groove. In Figure 1, the insulating layer 32 represents the bottom of the recessed feature 20.

[0075] In Figure 2, the front portion 54 of the alignment element 52 is located on the bottom side of the substrate structure 10. In Figure 2, the concave feature 20 is at least partially in the form of a through bore and / or through hole. The upper part of the concave feature 20 is located within the separation groove 24 of the upper metallized layer 30.

[0076] In Figures 1 and 2, the alignment element 52 is designed to contact the substrate structure 10 at the side surface 57 of the front portion 54. In Figure 1, the side surface 57 is not in contact with the substrate structure 10. In Figure 2, the side surface 57 is in contact with the substrate structure 10.

[0077] Considering that the concave feature 20 is a blind hole in Figure 1, with respect to plane P, the concave feature 20 is surrounded all around by the upper metallized layer 30, i.e., only by a radial size 26 of more than 1 mm starting from the boundary of the concave feature 20.

[0078] Considering that the concave feature 20 is part of a separation groove 24 extending parallel to the plane P in Figure 2, with respect to the plane P, the concave feature 20 is at least partially surrounded by the upper metallized layer 30 from at least two sides for a radial size 26 greater than 1 mm, starting from the boundary of the concave feature 20.

[0079] In Figure 2, the concave feature 20 is at least partly part of a separation groove 24 designed to form individual conductive sections of the upper metallized layer 30. The separation groove 24 forms at least partially the concave feature 20.

[0080] Preferably, the alignment element 52 has a circular, elongated shape. However, other shapes are also possible.

[0081] In particular, the front portion 54 of the alignment element 52 is flat. Figure 3 shows a cross-sectional view of a power semiconductor module 1. Module 1 has a substrate structure 10 comprising a bottom metallized layer 34 on the bottom side 14 and an upper metallized layer 30 on the upper side 12. The metallized layers 30 and 34 are attached to an insulating layer 32 on both sides 12 and 14, for example, as a metal coating or laminate. The insulating layer 32 is shown schematically, in particular, to indicate that it is at least twice as thick as the metallized layers 30 and 34.

[0082] The module housing 50 is attached and / or fastened to the substrate structure 10, for example, on an insulating layer 32, by bonding, which also serves to accommodate another substrate structure or auxiliary substrate structure if one exists. Furthermore, two power semiconductor elements 18 are supported on the upper side 12.

[0083] The power semiconductor elements 18 are electrically connected to the upper metallized layer 30, particularly by soldering or sintering. An insulating groove 24, which may also serve as a concave feature 20, may be located between two of the semiconductor elements. The power semiconductor elements 18 are electrically connected to each other. Terminal pads for electrically contacting the power semiconductor elements 18 with the external terminals of the module housing 50 are not shown.

[0084] The substrate structure 10 has separation grooves 24 in the upper metallized layer 30, the separation grooves 24 at least partially form and / or function at least partially as recessed features 20, and in particular provide separation patterns to form individual conductive sections of the upper metallized layer 30. Two of the recessed features 20 are located in the upper metallized layer 30 attached to the insulating layer 32 in an embodiment very similar to the recessed features 20 in Figure 1.

[0085] To simply illustrate the possible locations of the concave features 20, Figure 3 shows one of the concave features 20 located on each of the power semiconductor elements 18. Typically, the power semiconductor elements 18 do not have concave features 20 on their upper side and preferably have a flat top surface and / or no recess on the top.

[0086] Although Figure 3 does not show that the concave feature 20 is located in the insulating layer or the bottom metallized layer 34, this is also one of the options.

[0087] The concave feature 20, which is penetrated by the alignment element 52, is located only in the substrate structure 10, and specifically in the upper metallized layer 30. The concave feature 20 extends perpendicularly to the plane P on the upper side 12, passing through the entire thickness 31 of the upper metallized layer 30, and ends on the upper part of the insulating layer 32 supporting the upper metallized layer 30. In particular, the concave feature 20 is part of a separation groove 24 that extends across the plane P, but it may also be a blind hole.

[0088] The alignment element 52 has a rectangular shape in a cross-section parallel to the plane P. The front portion 54 of the alignment element 52 is particularly flat to contact the substrate structure 10, for example, the insulating layer 32. The side surface 57 of the front portion 54 is in contact with the upper metallized layer 30 for positioning along the plane P.

[0089] Figure 4 shows a power semiconductor module 1 formed by a substrate structure 10 whose upper side 12 is fastened to a module housing 50. The substrate structure 10 comprises a partially shown bottom plate 36 on which a bottom metallized layer 34, an insulating layer 32, and an upper metallized layer 30 (not shown) are arranged and / or fastened. A power semiconductor element 18 is bonded to the upper metallized layer 30 (not shown). Features not shown are housed in the module housing 50. Terminal pads, electrical connectors, etc., may serve to electrically connect the power semiconductor module 1 (not shown).

[0090] The module housing 50 has four side walls 62 and an upper cover 60 that substantially form the shape of the module housing 50. The side walls 62 and the upper cover 60 are integrally formed from each other, for example, an electrical insulating material.

[0091] Each of the side walls 62 has a contact surface on the side furthest from the upper cover 60. An alignment element 52 is integrally formed on the upper cover 60.

[0092] In this case, the bottom plate 36 is screwed into the module housing 50 from the bottom side 14 opposite the top side 12 in order to connect the entire substrate structure 10 to the housing 50 that houses the power semiconductor element 18. The substrate structure 10 is further joined via two abutting annular contact surfaces 38 on both the bottom plate 36 and the module housing 50.

[0093] In addition to or instead of this, the substrate structure 10 and the module housing 50 can be bonded together. Alternatively, or in addition to this, the substrate structure 10 and the module housing 50 may be in contact only via a sealing material.

[0094] The bottom plate 36 has a thickness 37 that is at least 2, 3, 4 or more times greater than the upper metallized layer 30.

[0095] In Figure 4, at least one upper metallized layer 30 is attached to the base plate 36, both on top of the base plate 36 and inside the module housing 50. The upper metallized layer 30 is surrounded by a contact surface 38. In addition, a bottom metallized layer 34 and an insulating layer 32 are provided on top of the base plate 36, below the upper metallized layer 30, and similarly inside the module housing 50.

[0096] In this embodiment, since the four mating recesses 17 are located on each of the four sides, particularly on the outer edge 16, the outer edge 16 of the base plate 36 still has a dogbone shape. The dogbone shape is typically used for positioning by the mating portion of the module housing 50.

[0097] However, in this case, the module housing 50 does not have a fitting portion to cover the outer edge 16. The outer edge 16 is not in contact with the module housing 50 and / or its fitting portion. The substrate structure 10 is not covered by the module housing 50 and / or its fitting portion in the side view. Therefore, in order to increase the cooling area, the fitting recess 17 can be omitted and the surface area of ​​the bottom side 14 of the substrate structure can be enlarged.

[0098] In Figure 4, the alignment element 52 acts as a support column configured to support the upper cover 60 of the module housing 50 relative to the substrate structure 10. Internally, one side of the alignment element 52 is coupled to the upper cover 60, and the other side is coupled to the substrate structure 19 via the concave feature 20.

[0099] When module 1 in Figure 4 is assembled, the internal alignment element 52 of the housing 50 penetrates at least partially through the substrate structure 10 in order to position the housing 50 relative to the substrate structure 10 along the plane P that aligns with the substrate structure 10. This makes the curing of the adhesive and / or screwing of the screws for joining the substrate structure 10 to the housing 50 easier and more accurate, resulting in product-by-process characteristics such as improved process reliability and a reduction in the occurrence of defective products.

[0100] The aspects of the embodiments described and illustrated above may be combined. [Explanation of symbols]

[0101] 1 Power semiconductor module, 10 Substrate structure, 12 Top side, 14 Bottom side, 16 Outer edge, 17 Mating recess, 18 Power semiconductor element, 20 Concave feature, 21 Size, e.g., diameter, 22 Depth, 24 Separation groove, 26 Radial size, 30 Top metallized layer, 31 Thickness, 32 Insulating layer, 33 Thickness, 34 Bottom metallized layer, 35 Thickness, 36 Bottom plate, 37 Thickness, 38 Contact surface, 50 Module housing, 52 Alignment element, 53 Size, e.g., diameter, 54 Front, 56 Length, 57 Side, 60 Top cover, 62 Side wall, P Plane.

Claims

1. A power semiconductor module (1), A module housing (50) having an alignment element (52), The substrate structure (10) is plate-shaped and comprises an upper side (12), an upper metallized layer (30) disposed on the upper side, a power semiconductor element (18) disposed on the upper side (12) and electrically connected to the upper metallized layer (30), and a concave feature (20) disposed on the upper side (12), wherein the substrate structure (10) is fastened to the module housing (50) to accommodate the power semiconductor element (18). The alignment element (52) penetrates the concave feature (20) from the upper side (12) and / or passes through the concave feature (20), thereby providing a mechanical engagement between the module housing (50) and the substrate structure (10) with respect to movement in at least one direction in a plane (P) along the upper side (12) of the power semiconductor module (1).

2. The power semiconductor module (1) according to the preceding claim, wherein the substrate structure (10) has an insulating layer (32) having the upper metallized layer (30) and optionally a bottom metallized layer (34) opposite the upper metallized layer (30), and in particular the insulating layer (32) comprises a ceramic material or a resin sheet for electrical insulation, and in particular the metallized layer or at least one metallized layer (32, 34) contains or is made of copper.

3. The power semiconductor module (1) according to any one of the preceding claims, wherein the substrate structure (10) has a bottom plate (36) on the bottom side (14) opposite to the upper side (12), and optionally the bottom plate (36) is bonded to the insulating layer (32), preferably via the bottom metallized layer (34), and optionally the bottom plate (36) comprises a metal, for example, in alloys and / or in composite materials, particularly AlSiC and / or MgSiC.

4. The power semiconductor module (1) according to any one of the two preceding claims, wherein the substrate structure (10) is fastened to the module housing (50) by a contact surface (38) of the bottom plate (36) or the insulating layer (32), and the contact surface (38) is circumferentially positioned with respect to the upper metallized layer (30).

5. The power semiconductor module (1) according to any one of the preceding claims, wherein the upper metallized layer (30) has a thickness of at least 0.5 mm (31).

6. The power semiconductor module (1) according to any one of the preceding claims, wherein the upper metallized layer (30) has separation grooves (24) to form individual conductive sections of the upper metallized layer (30), and the separation grooves (24) at least partially form the concave features (20), or a plurality of the concave features (20) for a plurality of the alignment elements (52).

7. The power semiconductor module (1) according to any one of the preceding claims, wherein the concave feature (20) is partially or completely surrounded by the upper metallized layer (30) in the plane (P) by a radial size (53) of at least 1 mm, starting from the boundary of the concave feature (20).

8. The alignment element (52) penetrates the upper metallized layer (30), as described in any one of the preceding claims, for the power semiconductor module (1).

9. The alignment element (52) penetrates the insulating layer (32), as described in any one of the preceding claims, for the power semiconductor module (1).

10. The alignment element (52) penetrates the bottom metallized layer (34), as described in any one of the preceding claims, for the power semiconductor module (1).

11. The alignment element (52) penetrates the bottom plate (36), as described in any one of the preceding claims, for the power semiconductor module (1).

12. The front portion (54) of the alignment element (52) is positioned at a distance from the substrate structure (10) or is in contact with the substrate structure (10), the power semiconductor module (1) according to any one of the preceding claims, wherein the distance is considered in a direction perpendicular to the plane (P).

13. The power semiconductor module (1) according to any one of the preceding claims, wherein the front portion (54) of the alignment element (52) is designed to contact the substrate structure (10) at least one side of the front portion (54).

14. The alignment element (52) is integrally formed with the module housing (50) and / or made of the same material as the module housing (50), as described in any one of the preceding claims, for the power semiconductor module (1).

15. The alignment element (52) is manufactured together with the module housing (50) by injection molding or transfer molding, as described in any one of the preceding claims, for the power semiconductor module (1).

16. The power semiconductor module (1) according to any one of the preceding claims, wherein the alignment element (52) is formed separately from the module housing (50) and / or is made of a different material from the module housing (50).

17. The power semiconductor module (1) according to any one of the preceding claims, wherein the alignment element (52) has at least a circular, polygonal, triangular, rectangular, square, and / or prismatic shape on its front portion (54) in a cross-sectional view.

18. The power semiconductor module (1) according to any one of the preceding claims, wherein the front portion (54) of the alignment element (52) is partially or completely flat.

19. The alignment element (52) has an elongated shape in a direction substantially perpendicular to the plane (P), as described in any one of the preceding claims, for the power semiconductor module (1).

20. The power semiconductor module (1) according to any one of the preceding claims, wherein the alignment element (52) and / or the concave feature (20) have a size (21, 53) of at least 0.7 mm along the plane (P), and / or the alignment element (52) has a length (56) of at least 1.0 mm, and / or the alignment element (52) and the concave feature (20) exhibit at least substantially the same size (21, 53), for example within ±5%, within the plane (P).

21. The power semiconductor module (1) according to any one of the preceding claims, wherein the outer edge (16) of the substrate structure (10) is not in contact with the module housing (50), for example, its mating portion, and / or the substrate structure (10) is not covered in particular by the module housing (50), for example, its mating portion, in a side view.

22. The power semiconductor module (1) according to any one of the preceding claims, wherein the substrate structure (10) is fastened, for example, by bonding using an adhesive and / or by screwing, for example, screws into the module housing (50), and during the fastening, for example, during the application or curing of the adhesive and / or during the screwing, the alignment element (52) penetrates the concave feature (20), thereby playing a role in positioning the module housing (50) relative to the substrate structure (10) along the plane (P).

23. The alignment element (52) serves as a support column configured to support the upper cover (60) of the module housing (50) relative to the substrate structure (10), as described in any one of the preceding claims, for the power semiconductor module (1).

24. A method for manufacturing a power semiconductor module (1) or a power semiconductor module (1) according to any one of the preceding claims, comprising: a module housing (50) having alignment elements (52); and a substrate structure (10) which is plate-shaped and has an upper side (12), an upper metallized layer (30) disposed on the upper side (12), a power semiconductor element (18) disposed on the upper side (12), and a concave feature (20) disposed on the upper side (12), wherein the module housing (50) is designed to accommodate the power semiconductor element (18), - The step includes positioning the module housing (50) on the upper side (12) of the substrate structure, wherein the alignment element (52) penetrates the concave feature (20) from the upper side (12) to position the module housing (50) relative to the substrate structure (10) along a plane (P) along the upper side (12), and further, - A method comprising the step of fastening the substrate structure (10) to the module housing (50) by joining and / or screwing.

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