Joint connection, power module assembly and method for attaching first joint partner to second joint partner

Abstract

The invention relates to a joining connection (1) for attaching a first joining partner (2) to a second joining partner (3), comprising a joining material (4) and an intermetallic phase layer (5), the joining material (4) being arranged between the first joining partner (2) and the second joining partner (3) and the intermetallic phase layer (5) being arranged between the joining partner (2) and the second joining partner (3). -the intermetallic phase layer (5) is arranged between the bonding material (4) and at least one of the first bonding partner (2) and the second bonding partner (3),-the intermetallic phase layer (5) has at least two regions different from each other, comprising at least one first region (6) having a first height (8) and at least one second region (7) having a second height (9). Furthermore, a power module assembly (11) and a method for attaching a first joining partner (2) to a second joining partner (3) are specified.

Description

Technical Field

[0001] This disclosure relates to a joining connector for attaching a first joining partner to a second joining partner, a power module assembly, and a method for generating the joining connector. Summary of the Invention

[0002] Embodiments of this disclosure relate to a particularly reliable joint connector. Further embodiments of this disclosure relate to a module assembly having such a joint connector and a method for producing such a joint connector.

[0003] This is achieved through the subject matter title of the independent claim. Further embodiments will be apparent from the dependent claims described below.

[0004] A bonding connector is described for attaching a first bonding mating member to a second bonding mating member. Exemplarily, the bonding connector is formed in a power semiconductor module having at least one power semiconductor device. The term "power" herein and hereinafter refers, for example, to a power semiconductor module, power semiconductor device, and / or power semiconductor chip suitable for handling voltages greater than 100 V and / or currents greater than 10 A (exemplarily, voltages up to 10 kV and ampere currents up to 5000 A).

[0005] The first mating member includes, for example, a first connecting portion, and / or the second mating member includes, for example, a second connecting portion. The first connecting portion and / or the second connecting portion are particularly formed of a conductive material. The first connecting portion and / or the second connecting portion comprise, for example, a metal or a metal alloy, or are composed of, a metal or a metal alloy. Exemplarily, the first connecting portion and / or the second connecting portion comprises, for example, at least one of copper (Cu), aluminum (Al), and nickel (Ni). In particular, the first connecting portion and / or the second connecting portion comprises or is composed of an alloy comprising at least two of the following materials: copper (Cu), aluminum (Al), and nickel (Ni).

[0006] Specifically, the first connecting portion is the metallized portion of the first mating member, and the second connecting portion is the metallized portion of the second mating member. The metallized portions of the first mating member and / or the second mating member (i.e., the first connecting portion and / or the second connecting portion) can be, for example, a backside metallized portion of the chip as a thin coating, or it can be a substrate metallized portion as, for example, a bulk metal, or it can be the entire backside surface of the chip, or it can be a portion of the surface of the substrate metallized portion. The substrate metallized portion may have at least a partial additional coating. In some cases, the connecting portion can be a terminal pin or a mating portion of a clamp.

[0007] The first and second mating members each extend within a main extending plane, which extends in a lateral direction. The first and second mating members are arranged opposite each other in a vertical direction, perpendicular to the lateral direction. Specifically, the first connecting portion faces the second connecting portion such that the first connecting portion is arranged opposite the second connecting portion in a vertical direction. Exemplarily, the first connecting portion completely overlaps the second connecting portion in a lateral direction in a plan view.

[0008] For example, at least one of the first connecting portion and the second connecting portion has a circular, elliptical, or polygonal (such as a quadrilateral) shape in a plan view. Exemplarily, the engaging connector has the same shape as the first connecting portion and / or the second connecting portion in a plan view. For example, in a plan view, the shape of at least one of the first connecting portion and the second connecting portion has a range equal to or greater than the shape of the engaging connector.

[0009] According to an embodiment, the bonding connector includes a bonding material. The bonding material is particularly formed of a conductive material. The bonding material includes, for example, a metal or metal alloy, or is composed of a metal or metal alloy. The bonding material includes, for example, at least one selected from tin (Sn), lead (Pb), silver (Ag), antimony (Sb), and copper (Cu). Specifically, the bonding material includes or is composed of an alloy comprising at least two of the following materials: tin (Sn), lead (Pb), silver (Ag), antimony (Sb), and copper (Cu). The bonding material may include other substances, such as rare earth materials or bismuth or indium, to influence material properties (e.g., wetting behavior and / or diffusion rate).

[0010] According to an embodiment, the bonding connector includes an intermetallic phase layer. The intermetallic phase layer includes at least one metal, such as a bonding material, and at least one metal from either the first connecting portion or the second connecting portion.

[0011] Exemplarily, during the method steps for producing the joined connector, the joining material is heated such that it melts and wets the corresponding joining portions, thereby creating a metallurgical bond. Exemplarily, atoms from the joining material and the joining portions diffuse across the interface between the joining material and the joining portions, thereby forming an intermetallic phase layer. That is, the intermetallic phase layer comprises or is composed of a metal alloy, the metal alloy being at least one of the metals of the joining material and at least one of the metals of one of the first joining portions or the second joining portion.

[0012] According to an embodiment of the coupling connector, a coupling material is arranged between a first coupling mating member and a second coupling mating member. Specifically, the coupling material is arranged between the first connecting portion and the second connecting portion. That is, the first coupling mating member, the coupling material, and the second coupling mating member are stacked on top of each other in a stacking direction oriented vertically.

[0013] According to an embodiment of the bonding connector, an intermetallic phase layer is disposed between the bonding material and at least one of the first and second bonding mating members. Specifically, the intermetallic phase layer is the interface region between the bonding material and at least one of the first and second bonding mating members. The intermetallic phase layer is in direct contact with the bonding material, for example. Exemplarily, the intermetallic phase layer is in direct contact with at least one of the first and second bonding mating members.

[0014] According to an embodiment of the joining connector, the intermetallic phase layer has at least two regions that are distinct from each other, including at least one first region having a first height and at least one second region having a second height. The height is the range of the intermetallic phase layer in the vertical direction.

[0015] Specifically, these different regions having a first height and a second height will not be compared with the roughness of the interface between the intermetallic phase layer and the bonding material, or the interface between the intermetallic phase layer and at least one of the first and second bonding mating members. Such roughness of the corresponding interfaces is typically due to manufacturing tolerances. That is, the difference between the first height and the second height is greater than the roughness of the corresponding interface of the intermetallic phase layer. The roughness is typically in the range of a few micrometers at most.

[0016] Specifically, the coupling connector provides mechanical stability for the first and second coupling mating parts, as well as electrical and / or thermal connections.

[0017] Soldering is a common bonding technique used in the assembly of power semiconductor devices and modules, for example, to bond a first bonding pair (i.e., a power semiconductor chip) to a second bonding pair (i.e., an isolation substrate) or vice versa, or to bond a substrate to a base plate. Conventional reflow soldering remains the most commonly used bonding technique. During a conventional soldering process, a conventional intermetallic phase layer is formed by the interdiffusion of materials at the interface between the conventional bonding material (i.e., conventional solder) and the bonding pair. This type of conventional intermetallic phase layer has a predominantly uniform height in the vertical direction. "Predominantly" means that variations in height may exist due to manufacturing tolerances.

[0018] However, the typical interface area between the substrate and the base plate is relatively large. This leads to localized stresses of varying magnitudes, for example, due to thermal cycling during operation. For instance, during thermal cycling, the thermomechanical stress at the corners of a conventionally welded joint is significantly greater than that in the central region. It is conceivable that the weakest area of ​​a conventionally welded joint could be located where the highest thermomechanical stress occurs.

[0019] In summary, such joint connectors with intermetallic phase layers having a first height and a second height can provide the following advantages in particular.

[0020] Because the height of the intermetallic phase layer affects the stress resistance of the welded joint (e.g., due to the improved hardness of the intermetallic phase layer compared to the bare bonding material), and therefore particularly affects reliability during thermal cycling, the intermetallic phase layer has a first region and a second region with different heights. Therefore, by locally modifying the height in this intentional way, the intermetallic phase layer is patterned, locally enhancing the reliability of the welded joint against thermomechanical stress.

[0021] Such patterned intermetallic phase layers lead to improved reliability of the joint with respect to thermomechanical stress. In particular, the patterned intermetallic phase layers result in higher local ultimate strength of the joint, especially in critical areas where stress maximum occurs, and thus lead to longer cycle times.

[0022] If multiple patterns of first and second heights exist, a hook-like cracking process can occur, which can suppress crack formation and delamination due to stress and thus improve reliability.

[0023] According to a further embodiment of the coupling connector, the first height and the second height differ from each other by at least 50% in the vertical direction. Exemplarily, the first height is greater than the second height, particularly the first height is at least 1.5 times the second height. Alternatively, the second height is greater than the first height, particularly the second height is at least 1.5 times the first height.

[0024] For example, at least one of the first height and the second height is at least 1 μm and at most 100 μm.

[0025] According to a further embodiment of the coupling connector, a first region is arranged in the central region of the coupling connector, and a second region is arranged in the peripheral region of the coupling connector that at least partially surrounds the central region.

[0026] Exemplarily, the central region is located at the centroid of the connecting member and extends laterally along an edge toward at least one of the first and second connecting portions. The peripheral region extends laterally along the edge region defining the central region of the connecting member. The peripheral region partially or completely surrounds the central region in the lateral direction.

[0027] The second region is arranged at least regionally or entirely within the outer region. For example, the second region surrounds the central region in a frame-like manner. The term "frame-like" is understood to be non-restrictive regarding the shape of the reinforcing structure.

[0028] According to a further embodiment of the connecting member, the second region is formed by several portions spaced apart from each other in the lateral direction, and each portion has a second height. Exemplarily, each portion of the second region has a second height. The portions of the second region are, for example, spaced apart from each other in the lateral direction.

[0029] If the second height is less than the first height, then portions of the second region are spaced apart from each other in the lateral direction by the first region. That is, for example, the first region is arranged between portions of the second region.

[0030] If the second height is greater than the first height, then portions of the second region are spaced apart from each other in the lateral direction by a bonding material and / or by at least one of the first connecting portion and the second connecting portion. That is, for example, the bonding material and / or at least one of the first connecting portion and the second connecting portion are arranged between portions of the second region.

[0031] According to a further embodiment of the connecting member, each part is arranged in a corner of the connecting member. If the connecting member, in particular at least one of the first and second connecting parts, has a polygonal shape in the plan view, then each part is arranged in a region located at one of the corners of the polygonal shape.

[0032] According to a further embodiment of the coupling connector, at least one of the first and second regions has a width of at least 100 μm in the lateral direction. The widths are the minimum ranges of the first and second regions in the lateral direction, respectively.

[0033] According to a further embodiment of the bonding connector, the intermetallic phase layer includes a plurality of first regions having a first height and a plurality of second regions having a second height. Each of the first regions has the same first height, and each of the second regions has the same second height.

[0034] According to a further embodiment of the connecting member, the first region and the second region are arranged laterally at virtual grid points of a virtual mesh. The virtual mesh is only used to illustrate the positions of the first region and the second region. The virtual mesh is, for example, a regular one-dimensional or regular two-dimensional mesh. If the virtual mesh is a regular two-dimensional mesh, then the virtual mesh is a polygonal mesh, such as a triangular mesh, a quadrilateral mesh, and especially a square mesh or a hexagonal mesh.

[0035] According to a further embodiment of the connecting member, each of the first regions is formed as a first strip, and each of the second regions is formed as a second strip. If the first and second regions are arranged on virtual grid points of a regular one-dimensional grid, then each first region forms a first strip, and each second region forms a second strip.

[0036] The strip has a range in width and length in the lateral direction. The length extends along the main extension direction of the strip. The length is greater than the width, specifically, the length is at least 20% or at least 50% greater than the width.

[0037] According to a further embodiment of the coupling connector, the first strip and the second strip are arranged alternately adjacent to each other in one of the lateral directions. In particular, the first strip and the second strip are arranged alternately adjacent to each other along an arrangement direction perpendicular to the main extension direction of the strips.

[0038] According to a further embodiment of the connecting member, the first region is each formed as a first quadrilateral, and the second region is each formed as a second quadrilateral. Exemplarily, the first quadrilateral and / or the second quadrilateral each have the same extent in the lateral direction. Specifically, the first quadrilateral and / or the second quadrilateral are each square with the same side length.

[0039] According to a further embodiment of the connecting member, the first quadrilateral and the second quadrilateral are arranged alternately adjacent to each other in the lateral direction, such that each first quadrilateral has an edge adjacent to one of the second quadrilaterals, and vice versa. That is, the first quadrilateral and the second quadrilateral form a checkerboard pattern.

[0040] According to a further embodiment of the connecting member, the first height continuously increases or decreases to the second height. In particular, the intermetallic phase layer gradually increases from the first height to the second height, wherein the first height and the second height represent the maximum and minimum ranges in the vertical direction, respectively.

[0041] According to a further embodiment of the coupling connector, the first height and the second height change periodically in one of the lateral directions, and the width of one period is at least 200 μm in the lateral direction. That is, if the coupling connector includes several first regions and second regions arranged alternately along each other, the maximum height of the first region corresponding to the first height and / or the minimum height of the second region corresponding to the second height are each spaced apart from each other by at least 200 μm in the lateral direction.

[0042] According to a further embodiment of the joining connector, the first height increases or decreases discontinuously to a second height. Exemplarily, the first height increases or decreases to a second height within an interface region between a first region and a second region. The interface region, for example, has a width in the lateral direction that is at least an order of magnitude smaller than the width of at least one of the first and second regions. Exemplarily, the intermetallic phase layer has a stepped shape in one of the first and second regions that are directly adjacent to each other in a side view.

[0043] According to a further embodiment, the joining connector is at least one of a welded connector, a diffusion welded connector, and a sintered connector.

[0044] According to a further embodiment of the bonding connector for a power module assembly, the power module assembly includes a semiconductor chip, and the first bonding mating member and the second bonding mating member include at least one of the following: a substrate and a base plate, a substrate and a terminal, a semiconductor chip and a substrate, and a terminal or clamp and a semiconductor chip.

[0045] The base plate, substrate, and / or terminals may be part of a power semiconductor module. The semiconductor chip is, in particular, a power semiconductor chip. Specifically, a first bonding mating member and a second bonding mating member are included in the power semiconductor module. In this case, at least one of the first and second bonding mating members is formed from a power semiconductor chip.

[0046] For example, the first bonding pair is a substrate and the second bonding pair is a base plate, or the first bonding pair is a substrate and the second bonding pair is a terminal, or the first bonding pair is a semiconductor chip and the second bonding pair is a substrate, or vice versa.

[0047] Furthermore, a power module assembly is described herein, which may include the coupling connectors as described above. Therefore, features relating to the coupling connectors are also disclosed with respect to the power module assembly, and vice versa.

[0048] According to an embodiment, the power module assembly includes a first mating member, particularly the first mating member described above.

[0049] According to an embodiment, the power module assembly includes a second mating member, particularly the second mating member described above.

[0050] According to an embodiment, the power module assembly includes a coupling connector, particularly the coupling connector described above.

[0051] According to an embodiment of the power module assembly, the bonding connector includes a bonding material and at least one intermetallic phase layer.

[0052] According to an embodiment of the power module assembly, bonding material is disposed between a first bonding mating member and a second bonding mating member.

[0053] According to an embodiment of the power module assembly, an intermetallic phase layer is arranged between the bonding material and at least one of the first bonding mating member and the second bonding mating member.

[0054] According to an embodiment of the power module assembly, the intermetallic phase layer has at least two regions that are different from each other, the at least two regions including at least one first region having a first height and at least one second region having a second height.

[0055] According to a further embodiment of the power module assembly, the first bonding mating member is a substrate, and the second bonding mating member is a power semiconductor device, or vice versa. That is, the power module assembly is specifically part of a power semiconductor module. The power semiconductor device may include a power semiconductor chip.

[0056] For example, a power semiconductor device is an electronic component configured to handle high-level electrical power as specified above. Power semiconductor devices are exemplarily configured to control and convert electrical power (e.g., from AC to DC, or vice versa), or to change the frequency of voltage and / or current via corresponding switching operations. Power semiconductor devices include, for example, at least one of, or are composed of at least one of, the following: thyristors, power metal-oxide-semiconductor field-effect transistors (MOSFETs), insulated-gate bipolar transistors (IGBTs), high electron mobility transistors (HEMTs), and power diodes.

[0057] For example, a power semiconductor module includes one or more power semiconductor devices together with other components (such as a substrate, base plate, heat sink, at least one terminal, and control circuitry).

[0058] For example, the bonding connector can be arranged between two of the following entities in the power semiconductor module: power semiconductor device, substrate, base plate, heat sink, at least one terminal, and control circuitry.

[0059] Furthermore, a method for attaching a first mating member to a second mating member is described herein, by means of which a mating connector as described above can be produced or is made possible. Therefore, features of the mating connector are also disclosed with respect to this method, and vice versa.

[0060] According to an embodiment of the method, a first mating member and a second mating member are provided.

[0061] According to an embodiment of the method, a bonding material is applied to a first mating member. The bonding material is applied, for example, to a first connecting portion.

[0062] According to an embodiment of the method, a second mating member is applied to the mating material. That is, the first mating member, the mating material, and the second mating member are stacked on top of each other in the stacking direction and are in direct and close contact with each other.

[0063] According to an embodiment of the method, heating an assembly comprising a first bonding mating member, a bonding material, and a second bonding mating member causes the formation of an intermetallic phase layer. During heating, the bonding material melts and wets, for example, a first connecting portion. During heating, atoms from the bonding material and the connecting portion diffuse across the interface between the bonding material and the first connecting portion.

[0064] Specifically, the subsequent cooling of the heating of the components causes the molten material of the bonding material to solidify and atoms from the bonding material to form an intermetallic phase layer.

[0065] According to an embodiment of the method, the intermetallic phase layer is modified to have at least two regions that are different from each other, the at least two regions including at least one first region having a first height and at least one second region having a second height.

[0066] This means that conventional joints prepared using existing standard solder alloys and / or standard welding processes can also be advantageously manipulated to improve reliability. Additionally, in addition to standard reflow processes with defined temperature profiles, the proposed method can provide further influence and variation options on the welding process by locally manipulating the joints.

[0067] According to a further embodiment of the method, when heating the assembly, a local magnetic field is applied to one of at least two regions, wherein the height of the intermetallic phase layer depends on the magnetic flux of the local magnetic field.

[0068] If magnetic flux is applied to the second region during the heating and / or cooling of the component, the second height is smaller than the first height. That is, the magnetic flux reduces the diffusion rate.

[0069] According to a further embodiment of the method, when heating the assembly, a local current is applied to one of at least two regions, wherein the height of the intermetallic phase layer depends on the current density of the local current.

[0070] If current is applied to the second region during the heating and / or cooling of the component, the second height is smaller than the first height. That is, the current reduces the diffusion rate.

[0071] According to a further embodiment of the method, while heating the component, additional heat is applied to one of at least two regions, wherein the height of the intermetallic phase layer depends on the temperature of the heat. For example, the additional heat is applied using a local heat source or a local thermal probe.

[0072] As an alternative to or supplement to applying additional heat, additional cooling is applied to one of at least one region, wherein the height of the intermetallic phase layer depends on the cooling temperature. For example, additional cooling is applied using a localized cooling source or a localized cooling probe.

[0073] According to a further embodiment of the method, the bonding material comprises at least two different material systems corresponding to at least two regions to be generated. For example, the material system of the bonding material disposed on a first region of the intermetallic phase layer to be generated differs from the material system of the bonding material disposed on a second region of the intermetallic phase layer to be generated. The material systems may differ in terms of their composition and / or the proportions of the compositions included in the two material systems.

[0074] According to a further embodiment of the method, the bonding material includes at least two different maximum doping concentrations corresponding to at least two regions to be generated. For example, the maximum doping concentration of the bonding material disposed on a first region of the intermetallic phase layer to be generated is different from the maximum doping concentration of the bonding material disposed on a second region of the intermetallic phase layer to be generated.

[0075] Exemplarily, the bonding material comprises a doped material with a maximum doping concentration. The maximum doping concentration is at most 2% or at most 1% per unit volume of bonding material. The doped material can be, for example, a rare earth material or, for example, bismuth (Bi) or indium (In). Exemplarily, the wettability and / or diffusion of the bonding material depend on the doping concentration.

[0076] If the maximum doping concentration in the first region is greater than the maximum doping concentration in the second region, then the first height in the intermetallic phase layer to be generated is greater than the second height, or vice versa.

[0077] Alternatively or additionally, the bonding material comprises at least two different doped materials corresponding to the at least two regions to be formed. For example, the doped material of the bonding material disposed on the first region of the intermetallic phase layer to be formed is different from the doped material of the bonding material disposed on the second region of the intermetallic phase layer to be formed.

[0078] According to a further embodiment of the method, the mating surfaces of the first mating member and / or the second mating member include at least two different metallization materials corresponding to at least two regions to be generated. For example, the metallization material of the first connecting portion disposed in the first region of the intermetallic layer to be generated is different from the metallization material disposed in the second region of the intermetallic layer to be generated.

[0079] In particular, the two metallizing materials may differ in at least one metal of the connecting portion described above.

[0080] According to a further embodiment of the method, the first mating surface of the first mating member and / or the second mating surface of the second mating member include at least two different surface roughnesses corresponding to at least two regions to be generated.

[0081] For example, the first engagement surface of the first mating member is the top surface of the first connecting portion facing the second mating member. Exemplarily, the second engagement surface of the second mating member is the bottom surface of the second connecting portion facing the first mating member.

[0082] For example, the surface roughness of the first bonding surface in a first region of the intermetallic phase layer to be formed differs from that in a second region of the intermetallic phase layer to be formed. For example, the surface roughness difference is at least 10% or at least 50%.

[0083] According to a further embodiment of the method, the first mating surface of the first mating member and / or the second mating surface of the second mating member include a diffusion barrier layer in a region corresponding to at least one of the two regions to be generated. Exemplarily, the diffusion barrier layer is applied by a coating process.

[0084] If a diffusion barrier layer is disposed on the second region, and the second height is less than the first height when the assembly is heated, then the diffusion barrier layer reduces or blocks diffusion in the second region and thus reduces or blocks the second height. Attached Figure Description

[0085] The accompanying drawings are included to provide further understanding. In the drawings, elements with the same structure and / or function may be referenced by the same reference numerals. It will be understood that the embodiments shown in the drawings are illustrative representations and are not necessarily drawn to scale.

[0086] Figure 1 A schematic diagram of a connecting member according to an exemplary embodiment is shown. Figure 2 and Figure 3 Each shows a schematic diagram of a method stage for producing a mating connector according to an exemplary embodiment, and Figure 4 and Figure 5 Each diagram shows a graph of the height of the intermetallic phase layer characterized by the joint connector according to an exemplary embodiment. Detailed Implementation

[0087] according to Figure 1 An exemplary embodiment of the coupling connector 1 attaches a first coupling mating member 2 to a second coupling mating member 3. A bonding material 4 and an intermetallic phase layer 5 are disposed between the first coupling mating member 2 and the second coupling mating member 3. Specifically, the intermetallic phase layer 5 comprises or is composed of the material of the bonding material 4 and the first connecting portion 12. That is, the intermetallic phase layer 5 is partially located within the bonding material 4 and the first connecting portion 12, wherein the height of the intermetallic phase layer 5 depends particularly on the wetting behavior and / or especially on... Figure 2 The diffusion rate is described in more detail in the text.

[0088] The first mating member 2 includes a first connecting portion 12, and the second mating member 3 includes a second connecting portion 13. The first connecting portion 12 and the second connecting portion 13 are each metallized portions of the respective mating members.

[0089] The first connecting portion 12, the intermetallic phase layer 5, the bonding material 4, and the second connecting portion 13 are arranged above each other along a stacking direction that is vertical. The intermetallic phase layer 5 is located within the interface between the bonding material 4 and the first connecting portion 12, and extends over the first region 6 and the second region 7.

[0090] A first region 6 is arranged in the central region of the connecting member 1, and a second region 7 is arranged in the peripheral region of the connecting member 1 that completely surrounds the central region in the lateral direction, extending perpendicular to the vertical direction. That is, in the plan view, the second region 7 completely surrounds the first region 6 in the lateral direction. The plan view corresponds to a view along the vertical direction on the connecting member 1.

[0091] The connecting member 1 has a first height 8 in the first region 6 and a second height 9 in the second region 7. The first height 8 is greater than the second height 9. The intermetallic phase layer 5 gradually increases from the second height 9 to the first height 8. In particular, the intermetallic phase layer 5 has a corresponding... Figure 4 The shape of one of the cycles shown extends from one of the minimum values ​​to the directly adjacent minimum value. That is, the first height 8 corresponds to the maximum height in the first region 6, and the second height 9 corresponds to the minimum height in the second region 7.

[0092] The width of the first region 6 is, for example, at least 100 μm in the lateral direction.

[0093] According to an exemplary embodiment, the first mating member 2 and the second mating member 3, which are mechanically and stably connected by the mating connector 1, are power module assembly 11.

[0094] For example, the first bonding mating member 2 is a substrate for a power semiconductor device, and the second bonding mating member 3 is a power semiconductor device. That is, in this case, the power module assembly 11 is a power semiconductor module.

[0095] For example, a power semiconductor device includes or is composed of at least one of the following: a thyristor, a power metal-oxide-semiconductor field-effect transistor (MOSFET), an insulated-gate bipolar transistor (IGBT), a high electron mobility transistor (HEMT), and a power diode.

[0096] according to Figure 2In an exemplary embodiment, an assembly including a first connecting portion 12, a bonding material 4, and a second connecting portion 13 is heated to generate an intermetallic phase layer 5. The assembly is then cooled. Specifically, this process is used to generate a bonding connector 1 having an intermetallic phase layer 5, which corresponds to... Figure 1 An exemplary embodiment of the invention.

[0097] During the heating and / or cooling of the component, a local magnetic field is applied to the second region 7. When the magnetic flux of the local magnetic field is applied to the second region 7, the diffusion rate in the second region 7 decreases compared to the first region 6. Due to the reduced diffusion rate in the second region 7, the resulting second height 9 in the second region 7 is smaller than the resulting first height 8 in the first region 6.

[0098] according to Figure 3 In an exemplary embodiment, a diffusion barrier layer 10 is disposed on a first engagement surface of the first engagement member 2, wherein the first engagement surface of the first engagement member 2 is the top surface of the first connecting portion 12 facing the second engagement member 3. The diffusion barrier layer 10 has a different height. This height increases from the edge of the first engagement surface to the central region of the first engagement surface.

[0099] During the heating and / or cooling of the component, the diffusion rate decreases depending on the height of the diffusion barrier layer 10. The diffusion rate is inversely proportional to the height of the diffusion barrier layer 10. That is, the second height 9 of the intermetallic phase layer 5 in the second region 7 is greater than the first height 8 obtained in the first region 6.

[0100] exist Figure 4 and Figure 5 The height of the intermetallic phase layer 5 is shown on the y-axis of the graph, which depends on the range of one of the intermetallic phase layers 5 along the lateral direction (shown on the x-axis).

[0101] according to Figure 4 and Figure 5 The intermetallic phase layer 5 includes a plurality of first regions 6 having a first height 8 and a plurality of second regions 7 having a second height 9. The first regions 6 and the second regions 7 are arranged alternately close to each other in the lateral direction.

[0102] exist Figure 4 In the diagram, the first height 8 continuously, and particularly gradually, decreases to the second height 9. That is, the intermetallic phase layer 5 has a sinusoidal shape comprising multiple periods, as shown in the side view.

[0103] For example, the maximum values ​​of the sinusoidal shape are spaced at least 200 μm apart in the lateral direction. That is, the period has a width of at least 200 μm.

[0104] The first height 8 and the second height 9 have the maximum height difference. The interface between the directly adjacent first region 6 and the second region 7 is, for example, located at a height of the intermetallic phase layer 5 corresponding to half of the maximum height difference.

[0105] exist Figure 5 In the diagram, the first height 8 decreases discontinuously to the second height 9. That is, within the interface region between the first region 6 and the second region 7, the first height 8 decreases to the second height 9. This means that the intermetallic phase layer 5 has a stepped shape comprising multiple cycles, as shown in the side view.

[0106] For example, the first region 6 is spaced at least 100 μm apart in the lateral direction. That is, the width of the first region 6 and the second region 7 in the lateral direction is each at least 100 μm.

[0107] Figure Labels 1. Connecting connector 2 First mating component 3 Second mating component 4. Bonding materials 5. Intermetallic phase layers 6. First District 7 Second Area 8 First Height 9 Second Height 10. Diffusion barrier layer 11 Power Module Components 12 First connecting part 13 Second connecting part

Claims

1. A coupling connector (1) for attaching a first coupling mating member (2) to a second coupling mating member (3), the coupling connector having: - Bonding material (4), and - Intermetallic phase layer (5), wherein, - The bonding material (4) is arranged between the first bonding mating member (2) and the second bonding mating member (3). - The intermetallic phase layer (5) is disposed between the bonding material (4) and at least one of the first bonding mating member (2) and the second bonding mating member (3). - The intermetallic phase layer (5) has at least two regions that are different from each other, the at least two regions including at least one first region (6) having a first height (8) and at least one second region (7) having a second height (9).

2. The connecting member (1) according to claim 1, wherein, - The first height (8) and the second height (9) differ from each other by at least 50% in the vertical direction.

3. The connecting member (1) according to any one of claims 1 or 2, wherein, - The first region (6) is arranged in the central region of the connecting member (1), and the second region (7) is arranged in the peripheral region of the connecting member (1) that at least partially surrounds the central region.

4. The connecting member (1) according to any one of claims 1 to 3, wherein, - The second region (7) is formed by several parts spaced apart from each other, and each part has the second height, and - Each part is arranged in the corner of the joint connector (1).

5. The connecting member (1) according to any one of claims 1 to 4. - At least one of the first region (6) and the second region (7) has a width of at least 100 μm in the lateral direction.

6. The connecting member (1) according to any one of claims 1 to 5, wherein, - The intermetallic phase layer (5) includes a plurality of first regions (6) having the first height (8) and a plurality of second regions (7) having the second height (9).

7. The connecting member (1) according to claim 6, wherein, - The first region (6) and the second region (7) are arranged on the virtual grid points of the virtual grid in the lateral direction.

8. The connecting member (1) according to any one of claims 6 or 7, wherein, - The first region (6) each forms a first strip, and the second region (7) each forms a second strip, and - The first strip and the second strip are arranged adjacent to each other alternately in one of the lateral directions.

9. The connecting member (1) according to any one of claims 6 or 7, wherein, - The first region (6) is formed as a first quadrilateral, and the second region (7) is formed as a second quadrilateral, and - The first quadrilateral and the second quadrilateral are arranged alternately adjacent to each other in the lateral direction, such that each first quadrilateral has an edge adjacent to one of the second quadrilaterals.

10. The connecting member (1) according to any one of claims 1 to 9, wherein, - The first height (8) continuously increases or decreases to the second height (9), or - The first height (8) increases or decreases discontinuously to the second height (9).

11. The connecting member (1) according to any one of claims 6 to 10, wherein, - The first height (8) of the first region (6) and the second height (9) of the second region (7) change periodically in one of the lateral directions, and the width of one period is at least 200 μm in the lateral direction.

12. The connecting member (1) according to any one of claims 1 to 11, wherein, The connecting member (1) is at least one of the following: - Welded connectors, - Diffusion welded connectors, and - Sintered connectors.

13. The bonding connector (1) for a power module assembly according to any one of claims 1 to 12, wherein the power module assembly comprises a semiconductor chip, wherein, The first mating member (2) and the second mating member (3) include at least one of the following: - Substrate and base plate, - Substrate and terminals, - The substrate and the semiconductor chip, and - Terminals or clamps and the semiconductor chip.

14. A power module assembly (11), comprising: - First mating component (2). - Second mating piece (3), and - Connecting connector (1), wherein, - The joint connector (1) includes a joint material (4) and at least one intermetallic phase layer (5). - The bonding material (4) is arranged between the first bonding mating member (2) and the second bonding mating member (3). - The intermetallic phase layer (5) is disposed between the bonding material (4) and at least one of the first bonding mating member (2) and the second bonding mating member (3), and - The intermetallic phase layer (5) has at least two regions that are different from each other, the at least two regions including at least one first region (6) having a first height (8) and at least one second region (7) having a second height (9).

15. The power module assembly (11) according to claim 14, wherein, - The first bonding pair (2) is a substrate for a power semiconductor device, and - The second bonding pair (3) is a power semiconductor device.

16. A method for attaching a first mating member (2) to a second mating member (3), the method comprising: - Provide a first mating part (2) and a second mating part (3). - Apply the bonding material (4) to the first bonding mating member (2), and - Apply the second mating member (3) to the mating material (4), and - Heating the assembly including the first mating member (2), the bonding material (4) and the second mating member (3) causes an intermetallic phase layer (5) to be formed. - Modify the intermetallic phase layer (5) to have at least two regions that are different from each other, the at least two regions including at least one first region (6) having a first height (8) and at least one second region (7) having a second height (9).

17. The method according to claim 16, wherein, While heating the component, at least one of the following is performed: - A local magnetic field is applied to one of the at least two regions, wherein the height of the intermetallic phase depends on the magnetic flux of the local magnetic field. - A local current is applied to one of the at least two regions, wherein the height of the intermetallic phase depends on the current density of the local current, and - Apply additional heat and / or additional cooling to one of the at least two regions, wherein the height of the intermetallic phase depends on the temperature of the heat.

18. The method according to any one of claims 16 or 17, wherein, The method includes at least one of the following: - The bonding material (4) comprises at least two different material systems corresponding to the at least two regions to be generated, and - The bonding material (4) includes at least two different maximum doping concentrations corresponding to the at least two regions to be generated.

19. The method according to any one of claims 16 to 18, wherein, The method includes at least one of the following: - The mating surfaces of the first mating member (2) and / or the mating surfaces of the second mating member (3) comprise at least two different metallization materials corresponding to the at least two regions to be generated. - The first mating surface of the first mating member (2) and / or the second mating surface of the second mating member (3) include at least two different surface roughnesses corresponding to the at least two regions to be generated.

20. The method according to any one of claims 16 to 19, wherein, - The bonding surface of the first bonding pair (2) and / or the bonding surface of the second bonding pair (3) includes a diffusion barrier layer (10) in the region corresponding to at least one of the two regions to be generated.

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