SYSTEM AND METHOD FOR MOUNTING A HOUSING TO A BASE PLATE OF A SEMICONDUCTOR MODULE

Abstract

A system comprises a pattern recognition unit (90), a pick-and-place unit (92), and a control unit (94), wherein the pattern recognition unit (90) is configured to determine the actual position of a connection surface (120), the connection surface (120) being arranged on or above a substrate (10) of a semiconductor module, and the substrate (10) being arranged on a base plate (80), wherein the pattern recognition unit (90) is further configured to determine the actual position of a first end (41) of a terminal element (4), the terminal element (4) being attached to a housing (7), and the housing (7) being arranged on the base plate (80) such that the substrate (10) is arranged within a volume defined by the housing (7), and the control unit (94) being configured toto determine a deviation between the actual position of the first end (41) of the connector (4) with respect to the actual position of the connection surface (120), and the pick-and-place unit (92) is configured to move to the actual position of the first end (41) as determined by the pattern recognition unit (90) and to pick up the first end (41) of the connector (4) and subsequently to move the first end (41) to the actual position of the connection surface (120) as determined by the pattern recognition unit (90).

Description

TECHNICAL AREA

[0001] The present disclosure relates to a system and a method for mounting a housing on a base plate of a semiconductor module, in particular a housing with connection elements attached to it. BACKGROUND

[0002] Power semiconductor module assemblies often contain one or more substrates arranged within a package. A semiconductor array with multiple controllable semiconductor devices (e.g., two IGBTs in a half-bridge configuration) or non-controllable semiconductor devices (e.g., arrays of diodes) is mounted on each of the at least one substrate. Each substrate typically has a substrate layer (e.g., a ceramic layer), a first metallization layer applied to one side of the substrate layer, and (optionally) a second metallization layer applied to the other side of the substrate layer. The controllable semiconductor devices are, for example, mounted on the first metallization layer. The one or more substrates may be arranged on a base plate. Electrical connectivity between the interior and exterior of the package can be implemented using terminals.One or more terminal elements can be (permanently) attached to the package in a suitable manner. A first end of each terminal element is positioned on one of the substrates and electrically coupled to it. However, due to tolerances that occur during the assembly of the semiconductor module, it cannot be guaranteed that the first ends of the one or more terminal elements will always be in their desired positions relative to the respective substrate when the semiconductor module is fully assembled. For this reason, larger areas on the respective substrates can be kept free of other components so that even if tolerances occur, a reliable connection between the one or more terminal elements and the respective substrates can be established. This, however, increases the size and therefore the cost of the semiconductor module.

[0003] There is a need for a system and a process that make it possible to assemble a semiconductor module in a space-saving and cost-effective way. OVERVIEW

[0004] A system comprises a pattern recognition unit, a pick-and-place unit, and a control unit, wherein the pattern recognition unit is configured to determine the actual position of a connection surface, the connection surface being arranged on or above a substrate of a semiconductor module, and the substrate being arranged on a base plate; the pattern recognition unit is further configured to determine the actual position of a first end of a connector, the connector being attached to a housing, and the housing being arranged on the base plate such that the substrate is located within a volume defined by the housing; the control unit is configured to determine a deviation between the actual position of the first end of the connector with respect to the actual position of the connection surface; and the pick-and-place unit is configured toto move to the actual position of the first end as determined by the pattern recognition unit, to pick up the first end of the connecting element and subsequently to move the first end to the actual position of the connecting surface as determined by the pattern recognition unit.

[0005] A method comprises determining the actual position of a connection surface using a pattern recognition unit, wherein the connection surface is arranged on or above a substrate of a semiconductor module and the substrate is arranged on a base plate. The method further comprises determining the actual position of a first end of a terminal element using the pattern recognition unit, wherein the terminal element is attached to a housing and the housing is arranged on the base plate such that the substrate is located within a volume defined by the housing.The procedure further includes determining a deviation between the actual position of the first end of the connector element with respect to the actual position of the connection surface, moving a pick-and-place unit to the actual position of the first end determined by the pattern recognition unit, picking up the first end of the connector element using the pick-and-place unit, and subsequently moving the first end to the actual position of the connection surface as determined by the pattern recognition unit using the pick-and-place unit.

[0006] The invention can be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale; rather, the focus is on illustrating the principles of the invention. Furthermore, identical reference numerals in the figures denote corresponding parts in the different views. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a cross-sectional view of a semiconductor module. Fig. Figure 2 is a three-dimensional view of a housing with several connection elements attached to it. Fig. 3, which Fig. Figures 3A to 3C contain schematic top views of base plates with substrates arranged on them. Fig. Figure 4 schematically shows a system according to embodiments of the disclosure. Fig. Figure 5 schematically shows a side wall of a housing with attached connection elements. Fig. 6, which Fig. The diagram, which contains 6A to 6C, schematically shows various connection elements. Fig. Figure 7 schematically shows a tool for positioning the first end of a connection element on a substrate. Fig. Figure 8 schematically shows a method according to embodiments of the disclosure. DETAILED DESCRIPTION

[0007] The following detailed description refers to the accompanying drawings. The drawings show specific examples in which the invention can be implemented. It is understood that the features and principles described in relation to the various examples can be combined with one another, unless expressly stated otherwise. In the description and in the claims, designations of certain elements as "first element," "second element," "third element," etc., are not to be understood as enumerative. Rather, such designations merely serve to name different "elements." That is to say, for example, that the presence of a "third element" does not require the presence of a "first element" and a "second element."An electrical conductor or electrical connection, as described here, can be a single electrically conductive element or at least two single electrically conductive elements connected in series and / or parallel. Electrical conductors and electrical connections can contain metal and / or semiconductor material and can be permanently electrically conductive (i.e., non-switchable). A semiconductor body, as described here, can be made of (doped) semiconductor material and can be a semiconductor chip or contained within a semiconductor chip. A semiconductor body has electrically connecting pads and contains at least one semiconductor element with electrodes.

[0008] Referring to Fig. Figure 1 shows a cross-sectional view of a semiconductor module 100. The semiconductor module 100 comprises a package 7 and a substrate 10. The substrate 10 contains a dielectric insulating layer 11, a (structured) first metallization layer 111 attached to the dielectric insulating layer 11, and a (structured) second metallization layer 112 attached to the dielectric insulating layer 11. The dielectric insulating layer 11 is located between the first and second metallization layers 111 and 112.

[0009] Each of the first and second metallization layers 111, 112 can consist of or contain one of the following materials: copper; a copper alloy; aluminum; an aluminum alloy; any other metal or alloy that remains solid during operation of the power semiconductor module assembly. The substrate 10 can be a ceramic substrate, that is, a substrate in which the dielectric insulating layer 11 is a ceramic, e.g., a thin ceramic layer. The ceramic can contain or consist of one of the following materials: aluminum oxide, aluminum nitride, zirconium oxide, silicon nitride, boron nitride, or any other dielectric ceramic. The dielectric insulating layer 11 can, for example, consist of or contain one of the following materials: Al₂O₃, AlN, SiC, BeO, or Si₃N₄. The substrate 10 can, for example, be...The substrate 10 can be a Direct Copper Bonding (DCB) substrate, a Direct Aluminum Bonding (DAB) substrate, or an Active Metal Brazing (AMB) substrate. Furthermore, the substrate 10 can be an insulated metal substrate (IMS). An insulated metal substrate generally has a dielectric insulating layer 11 containing (filled) materials such as epoxy resin or polyimide. The material of the dielectric insulating layer 11 can, for example, be filled with ceramic particles. Such particles can be, for example, SiO2, Al2O3, AlN, or BN and can have a diameter between approximately 1 µm and approximately 50 µm. The substrate 10 can also be a conventional printed circuit board (PCB) with a non-ceramic dielectric insulating layer 11. For example, a non-ceramic dielectric insulating layer 11 can consist of or contain a cured resin.

[0010] The substrate 10 is arranged in a housing 7. In the case of the Fig. In the example shown, the substrate 10 is arranged on a base plate 80, which forms a base surface of the housing 7, while the housing 7 itself only has side walls and a cover. The cover of the housing 7 is generally optional and can also be omitted. It is generally possible for more than one substrate 10 to be arranged on a single base plate 80 and within the same housing 7.

[0011] One or more semiconductor bodies 20 can be arranged on each of the one or more substrates 10. Each of the semiconductor bodies 20 arranged on the substrate 10 can contain a diode, an IGBT (insulated-gate bipolar transistor), a MOSFET (metal-oxide-semiconductor field-effect transistor), a JFET (junction field-effect transistor), a HEMT (high-electron-mobility transistor), or any other suitable controllable or non-controllable semiconductor element.

[0012] One or more semiconductor bodies 20 can form a semiconductor array on one or more substrates 10. In Fig. Figure 1 shows, by way of example, only a substrate 10 and two semiconductor bodies 20 arranged on it. The second metallization layer 112 of the substrate 10 in Fig. 1 is a continuous layer. The first metallization layer 111 is in the Fig. In the example shown, a structured layer is present. "Structured layer" means that the first metallization layer 111 is not a continuous layer, but contains voids between different sections of the layer. Such voids are in Fig. Figure 1 is shown schematically. The first metallization layer 111 in this example contains four different sections. Different semiconductor bodies 20 can be mounted on the same or different sections of the first metallization layer 111. Different sections of the first metallization layer may not have an electrical connection or may be electrically connected to one or more other sections, e.g., using bond wires 3. Electrical connections 3 may also include, for example, connection plates or busbars, to name just a few examples. The one or more semiconductor bodies 20 may be electrically and mechanically connected to the substrate 10 by an electrically conductive bonding layer 30. Such an electrically conductive bonding layer may be a solder layer, a layer of an electrically conductive adhesive, or a layer of sintered metal powder, e.g.,a sintered silver powder.

[0013] The in Fig. The semiconductor module 100 shown in Figure 1 further includes terminal elements 4. The terminal elements 4 are electrically connected to the first metallization layer 111 and establish an electrical connection between the inside and outside of the housing 7. The terminal elements 4 can be electrically connected to the first metallization layer 111 at a first end 41, while a second end 42 of the terminal elements 4 protrudes from the housing 7. The terminal elements 4 can be electrically contacted from the outside at their second end 42. The terminal elements 4 are shown in Figure 1. Fig. The connection elements 4 shown in Figure 1 are only examples. Connection elements 4 can be implemented in any other way and can be located in any other position. For example, one or more connection elements 4 can be located close to or adjacent to the side walls of the housing 7. The connection elements 4 can be attached to the housing 7, as shown below in relation to Fig. 2 is described. Any other suitable implementation is generally possible. The terminal elements 4 can, for example, consist of or contain a metal such as copper, aluminum, gold, silver, or any alloys thereof. The terminal elements 4 can be electrically and mechanically connected to the substrate 10 by an electrically conductive connecting layer (not specifically shown for the terminal elements 4). Such an electrically conductive connecting layer can generally be a solder layer, a layer of an electrically conductive adhesive, or a layer of a sintered metal powder, e.g., a sintered silver powder.

[0014] Conventional semiconductor modules 100 generally contain an encapsulation or potting compound 5. The potting compound 5 may, for example, consist of or contain a cross-linked silicone gel, or it may be a rigid molding compound. The potting compound 5 may at least partially fill the interior of the housing 7, thereby covering the components and electrical connections arranged on the substrate 10. The terminal elements 4 may be partially embedded in the potting compound 5. However, at least their second ends 42 are not covered by the potting compound 5 and protrude through the housing 7 from the potting compound 5 to the outside of the housing 7. The potting compound 5 is designed to protect the components and electrical connections within the semiconductor module 100, particularly within the housing 7, from certain environmental conditions and mechanical damage.

[0015] Referring to Fig. Figure 2 schematically depicts a housing 7, wherein the housing 7 has side walls and several connection elements 4 attached to the side walls. When the housing 7 is mounted on a base plate 80 to form a semiconductor module (see, for example, the semiconductor module 100 in Figure 2), the housing 7 is shown schematically. Fig. 1) The connection elements 4 are generally already attached to the housing 7. That is, when the housing 7 is arranged on the base plate 80, the first ends 41 of the connection elements 4 are arranged in fixed positions with respect to the housing 7, the base plate 80, and thus with respect to the one or more substrates 10 arranged on the base plate 80. When the housing 7 has been arranged on and attached to the base plate 80, each first end 41 of the first ends 41 of the one or more connection elements 4 can be permanently connected to a respective one or more substrates 10.

[0016] Now, with reference to Fig. 3A shows two substrates 101, 102 schematically on a base plate 80. Fig. Figure 3A schematically shows the two substrates 101 and 102 in a desired position on the base plate 80. However, due to normal manufacturing tolerances, it cannot always be guaranteed that the substrates 101 and 102 will actually always be mounted in their desired positions on the base plate 80. The positions of the substrates 101 and 102 can vary to a certain extent. In general, a displacement (shifting or rotation) of up to a few millimeters is possible. For various applications, the following may occur: Fig. In the arrangements shown in Figure 3, the first metallization layers 111 arranged on the respective dielectric insulating layers 11 are visible. Semiconductor bodies and electrical connections (bonding wires) are also shown schematically. Fig. Figure 3 schematically shows several connection surfaces 120 on each of the substrates 101, 102. The connection surfaces 120 are areas on the substrates 101, 102 (i.e., on the first metallization layers 111) to which first ends 41 of connection elements 4 can be attached. As described above, connection elements 4 can be attached to a housing 7 of the semiconductor module. The housing 7 is placed on the base plate 80 after the substrates 101, 102 have been placed on it. Since the connection elements 4 are attached to the housing 7, the position of the first ends 41 with respect to the housing 7 is generally fixed. The housing 7 is generally positioned on the base plate 80 such that the side walls of the housing 7 extend along the edges of the base plate 80. That is, the positions of the first ends 41 of the one or more connection elements 4 with respect to the base plate 80 are also essentially fixed.However, certain tolerances may also occur when the housing 7 is mounted on a base plate 80.

[0017] Due to the tolerances that may occur when the substrates 101, 102 are mounted on the base plate 80 and when the housing 7 is mounted on the base plate 80, there is a risk that the first ends 41 will not be aligned with their respective connecting surfaces 120 when the housing 7 is in its final mounting position on the base plate 80. Fig. Figure 3B schematically shows the desired positions of the substrates 101, 102 (dashed lines) and their actual positions (solid lines), which, in this example, differ from the desired positions due to manufacturing tolerances during the step of attaching the substrates 101, 102 to the base plate 80. If a substrate 101, 102 is not positioned in its desired position on the base plate 80, this can result in the first ends 41 of the connecting elements 4 attached to the housing 7 being positioned at a certain distance from the respective connecting surfaces 120, if the position of the first ends 41 is chosen to be aligned with the desired position of the respective connecting surfaces 120.

[0018] For this reason, enlarged connection surfaces 124 can be provided on the substrates 101, 102, as shown in Fig. Figure 3C is shown schematically. This means that more space can be reserved on the individual substrates 101, 102 to connect the first ends 41 of the one or more connection elements 4 than is actually necessary to form the connection. No other elements of the semiconductor module may be arranged on the enlarged connection surfaces 124. Regardless of any tolerances during the steps of mounting the substrates 101, 102 on the base plate 80 and mounting the housing 7 with the attached connection elements 4 on the base plate 80, the first ends 41 of the one or more connection elements 4 are always arranged on one of the enlarged connection surfaces 124. However, providing enlarged connection surfaces 124 on a substrate 10 increases the size of the semiconductor module and thus also its cost.

[0019] Referring to Fig. Figure 4 is a system schematically depicted according to embodiments of the disclosure. The described system makes it possible to correctly position the first ends 41 of one or more connection elements 4 on the respective connection surfaces 120 on the one or more substrates 101, 102. The size of the connection surfaces 120 does not need to be increased. Each connection surface 120 only needs to be large enough to be able to form a stable connection between the first ends 41 of the connection elements 4 and the respective connection surfaces 120. No tolerances need to be taken into account. In this way, the semiconductor module can be manufactured in a small size and at low cost.

[0020] A system according to embodiments of the disclosure comprises a pattern recognition unit 90, a pick-and-place unit 92, and a control unit 94. The pattern recognition unit 90 is configured to determine the actual position of a connection surface 120. As described above, the connection surface 120 is arranged or provided on a substrate 10 of a semiconductor module, and the substrate 10 is arranged on a base plate 80. It is also conceivable that a connection surface 120 could be arranged above the substrate, e.g., on the top surface of a semiconductor chip 0, instead of or in addition to a connection surface 120 on the substrate 10. The pattern recognition unit 90 is further configured to determine the actual position of a first end 41 of a terminal element 4.The connecting element 4 is attached to a housing 7, and the housing 7 is positioned on the base plate 80 such that the substrate 10 is located within a volume defined by the housing 7. The control unit 94 is configured to detect any deviation between the actual position of the first end 41 of the connecting element 4 and the actual position of the connection surface 120, and the pick-and-place unit 92 is configured to move to the actual position of the first end 41, as determined by the pattern recognition unit 90, pick up the first end 41 of the connecting element 4, and subsequently move the first end 41 to the actual position of the connection surface 120 as determined by the pattern recognition unit 90.In particular, the pick-and-place unit 92 moves the first end 41 to the actual position of the connection surface 120 if the actual position of the first end 41 differs from the actual position of the connection surface 120. If the actual position of the first end 41 corresponds to the actual position of the connection surface 120, it is generally not necessary to move the first end 41 before forming the connection. Once the first end 41 is aligned with the respective connection surface 120, a permanent electrical and mechanical connection can be formed between the first end 41 and the connection surface 120.

[0021] Moving the first end 41 to the actual position of the connection surface 120 may not be possible with conventional connection elements 4. Conventional connection elements 4 are generally relatively rigid and do not allow any significant movement of the first end 41. However, as mentioned above, the actual position of the first end 41 of a connection element 4 can deviate from the actual position of the connection surface 120 by up to a few millimeters. Therefore, the housing 7 can be equipped with connection elements 4 that are flexible to a certain degree. Fig. Figure 5 schematically shows a side wall of a housing 7 with two attached connection elements 4. Each of the connection elements 4 in this example has a flexible section 48. The flexible section 48 allows movement of the first end within a defined radius r. This radius r can be up to several millimeters, e.g., between 0 and 5 mm. In the case of the Fig. In the example shown in Figure 5, the flexible section 48 is implemented by means of a meandering shape of the connecting element 4 in a section between the side wall of the housing 7 and the first end 41. However, this is only one example. The flexible section 48 can generally be implemented in any suitable way. For example, the flexible section 48 can have a stack comprising several flat-woven strands stacked on top of each other. According to yet other examples, the flexible section 48 can have one or more braided wires, each of which comprises several separate wires braided together to form the braided wire. It is even possible for the flexible section 48 to have several electrically conductive films stacked on top of each other. Any other suitable implementation is also possible.

[0022] The first end 41 can be formed by a section of the connecting element 4 extending parallel to the base plate 80 and the one or more substrates 101, 102 arranged thereon, when the one or more substrates 101, 102 and the housing 7 are mounted on the base plate 80, as exemplified in Fig. Figure 4 illustrates this. It is generally possible to pick up such a flat first end 41 using a suitable pick-and-place unit 92. However, according to further embodiments, the first end 41 of a connecting element 4 can have a first section extending parallel to the base plate 80 and the one or more substrates 101, 102 arranged thereon, and a second section extending in a direction perpendicular to the base plate 80 and the one or more substrates 101, 102 arranged thereon. Alternatively (instead of the second section), a projection 46 can be connected to the first end 41, wherein the first end 41 extends parallel to the base plate 80 and the one or more substrates 101, 102 arranged thereon, and the projection 46 extends in a direction perpendicular to the base plate 80 and the one or more substrates 101, 102 arranged thereon.A lead 46 associated with the first end 41 is exemplified in . Fig. 5 shown. In the Fig. In the example shown in section 5, the projection 46 has the shape of a sleeve. In a case where Fig. In the alternative example shown in 6A, the projection 46 has the shape of a simple pin, with the pin having a round cross-section. In a Fig. In the alternative example shown in 6B, the projection 46 has the shape of a pin, with the pin having a square cross-section.

[0023] In the Fig. 6A and Fig. In the examples shown in Figure 6B, the flexible section 44 is realized by means of a meandering shape of the connecting element 4 in a section between the side wall of the housing 7 and the first end 41, similar to what is shown in relation to Fig. 5 was described. Referring to Fig. Alternatively, in 6C, it is also possible to implement at least part of the connection element 4 (e.g., part of the connection element 4 extending between the side wall of the housing 7 and the respective substrate 10) using a simple wire. The wire can have a certain thickness to prevent breakage but can be flexible enough to allow movement of at least the first end 41 within a defined radius. In this example, a first section of a first end 41 of the wire can extend parallel to the base plate 80 and the respective substrate 10 when the housing 7 is arranged on the base plate 80 (the housing 7 is in the Fig. 6A, Fig. 6B and Fig. (6C not specifically shown), and a second section of the first end 41 can extend in a direction perpendicular to the base plate 80 and the respective substrate 10 when the housing 7 is arranged on the base plate 80.

[0024] The projection 46, or the second section of the first end 41, which extends in a direction perpendicular to the base plate 80 and the respective substrate 10 when the housing 7 is arranged on the base plate 80, facilitates the handling and repositioning of the first end 41 by means of the pick-and-place unit 92. Referring to Fig. 7. The pick-and-place unit 92 can further be configured to form a permanent connection between the first end 41 of the connecting element and the connecting surface 120. In this example, the pick-and-place unit 92 can include a sonotrode, a transducer, and a suction device (the transducer and the suction device are shown in Fig. 7 (not explicitly shown). The transducer can be coupled to the sonotrode and configured to cause the sonotrode to vibrate. The sonotrode can have a channel extending through the interior of the sonotrode and having at least two openings to the outside of the sonotrode. The suction device can be coupled to a first of the at least two openings and can be configured to cause the first end 41 of the connecting element 4, or a projection 46 connected to the first end 41, to be drawn towards a second of the at least two openings. This is shown in Fig. Figure 7 schematically illustrates a projection 46. In this example, the pick-and-place unit 92 picks up the first end 41 by inserting the projection 46 into the channel formed in the sonotrode. The suction device draws the projection 46 into the channel, allowing the pick-and-place unit 92 to pick up the first end 41 and move it to its desired position on the joining surface 120. The pick-and-place unit 92 can then place the first end 41 on the joining surface and perform an ultrasonic welding process, thereby joining the first end 41 to the joining surface. That is, the pick-and-place unit 92 itself can perform the joining process.

[0025] Picking up the first end 41 by means of a suction device is, however, only one example. The pick-and-place unit 92 can pick up the first end 41 or the projection 46 in general in any other suitable way. For example (example not specifically shown), the pick-and-place unit 92 can have a sonotrode, a transducer, and a gripping tool. The transducer can be coupled to the sonotrode and can be configured to vibrate the sonotrode. The gripping tool can be configured to grip the first end 41 of the connecting element 4 or a projection 46 connected to the first end 41.

[0026] According to another example, the pick-and-place unit 92 can be configured only to move the first end 41 to its desired position on the connection surface 120. An additional tool can then be used to form the connection. That is, the system can still include a connection unit, wherein the connection unit is separate and independent from the pick-and-place unit 92 and is configured to form a permanent connection between the first end 41 of the connector and the connection surface 120. In this example, the connection unit can include a transducer and a sonotrode, wherein the transducer is coupled to the sonotrode and configured to vibrate the sonotrode.The pick-and-place unit 92 can have a channel and a suction device, the channel extending through the pick-and-place unit 92 and having at least two openings to the outside of the pick-and-place unit 92. The suction device is coupled to a first of the at least two openings and is configured to cause the first end 41 of the connecting element 4 or a projection 46 connected to the first end 41 to be drawn towards a second of the at least two openings. Alternatively, the pick-and-place unit 92 can have a gripping tool configured to grip the first end 41 of the connecting element 4 or a projection 46 connected to the first end 41.

[0027] In order to pick up the first end 41, the pick-and-place unit 92 must move to the actual position of the first end 41. The actual position of the first end 41 can be determined using suitable pattern recognition techniques. Pattern recognition techniques are generally known in relation to semiconductor modules. For example, pattern recognition techniques are known that can be used to precisely place bond wires on a substrate or a semiconductor device. Such pattern recognition techniques can be used similarly to determine the exact position of the first end 41 of a terminal element 4. For example, one or more images of the base plate 80 and the one or more substrates 10 arranged on it can be taken.According to embodiments of the disclosure, the pattern recognition unit 90 can therefore have at least one camera, wherein the pattern recognition unit 90 is configured to take at least one picture of the base plate 80 and the substrate 10 arranged thereon by means of the at least one camera.

[0028] Pattern recognition systems are capable of recognizing and accurately determining characteristic patterns on the surface of the base plate 80 and the one or more substrates 10 arranged on it. For example, two or more points in the captured image(s) can be automatically recognized by a suitable system to create a so-called reference system. To compensate for the displacement and / or rotation of a substrate 10 on the base plate 80, or more precisely, a displacement and / or rotation of a substrate 10 with respect to a standard coordinate system defined by the respective pattern recognition unit 90, the at least two points can be used to generate a mathematical function that can compensate for any displacements and / or rotations.This means that a displacement of at least two points from a standard coordinate system can be determined, and subsequently the actual positions of one or more substrates 10 and / or all elements arranged on one or more substrates 10 can be determined based on the determined displacement of the two points. However, pattern recognition can alternatively be implemented in any other suitable way.

[0029] The same or other pattern recognition techniques can also be used to determine the actual position of the connection surface 120. Once the actual position of the first end 41 and the actual position of the respective connection surface 120 are known, it can be determined whether the positions correspond. If the actual position of the first end 41 and the actual position of the connection surface 120 do not correspond, the first end 41 can be moved to the actual position of the connection surface 120 using the pick-and-place unit 92. Specifically, the pick-and-place unit 92 moves to the actual position of the first end 41 determined by the pattern recognition unit 90, picks up the first end 41 of the connection element 4, and then moves the first end 41 to the actual position of the connection surface 120 as determined by the pattern recognition unit 90.Then a permanent connection can be formed between the first end 41 and the connecting surface 120.

[0030] Referring to Fig.Section 8 now schematically illustrates a method according to embodiments of the disclosure. The method comprises determining the actual position of a connection surface 120 by means of a pattern recognition unit 90 (step 801), wherein the connection surface 120 is arranged on a substrate 10 of a semiconductor module and the substrate 10 is arranged on a base plate 80. The method further comprises determining the actual position of a first end 41 of a terminal element 4 by means of the pattern recognition unit 90 (step 802), wherein the terminal element 4 is attached to a housing 7 and the housing 7 is arranged on the base plate 80 such that the substrate 10 is arranged within a volume defined by the housing 7.The procedure further includes determining a deviation between the actual position of the first end 41 of the connector 4 with respect to the actual position of the connecting surface 120 (step 803), moving a pick-and-place unit 92 to the actual position of the first end 41 as determined by the pattern recognition unit 90 (step 804), picking up the first end 41 of the connector 4 by means of the pick-and-place unit 92 (step 805) and subsequently moving the first end 41 to the actual position of the connecting surface 120 as determined by the pattern recognition unit 90 by means of the pick-and-place unit 92 (step 806).

[0031] The method may further include forming a permanent connection between the first end 41 of the connecting element 4 and the connecting surface 120. According to some examples, forming a permanent connection between the first end 41 of the connecting element 4 and the connecting surface 120 may involve performing an ultrasonic welding process.

Claims

[1] A system comprises a pattern recognition unit (90), a pick-and-place unit (92) and a control unit (94), wherein the pattern recognition unit (90) is configured to determine an actual position of a connecting surface (120), wherein the connecting surface (120) is arranged on or above a substrate (10) of a semiconductor module and the substrate (10) is arranged on a base plate (80), the pattern recognition unit (90) is further configured to determine an actual position of a first end (41) of a connection element (4), wherein the connection element (4) is attached to a housing (7) and the housing (7) is arranged on the base plate (80) such that the substrate (10) is arranged within a volume defined by the housing (7), the control unit (94) is designed to detect a deviation between the actual position of the first end (41) of the connecting element (4) in relation to the actual position of the connecting surface (120), and the pick-and-place unit (92) is configured to move to the actual position of the first end (41) determined by the pattern recognition unit (90), to pick up the first end (41) of the connecting element (4) and subsequently to move the first end (41) to the actual position of the connecting surface (120) as determined by the pattern recognition unit (90). [2] System according to claim 1, wherein the pick-and-place unit (92) is further configured to form a permanent connection between the first end (41) of the connecting element (4) and the connecting surface (120). [3] System according to claim 2, wherein the pick-and-place unit (92) comprises a sonotrode, a transducer and a suction device, wherein the transducer is coupled to the sonotrode and is designed to vibrate the sonotrode in order to form a permanent connection between the first end (41) of the connecting element and the connecting surface (120), the sonotrode has a channel extending through the interior of the sonotrode and has at least two openings to the outside of the sonotrode, and the suction device is coupled to a first of the at least two openings and is designed to cause the first end (41) of the connecting element (4) or a projection (46) connected to the first end (41) to be sucked towards a second of the at least two openings. [4] System according to claim 2, wherein the pick-and-place unit (92) comprises a sonotrode, a transducer and a gripping tool, wherein the transducer is coupled to the sonotrode and is designed to vibrate the sonotrode in order to form a permanent connection between the first end (41) of the connecting element and the connecting surface (120), and The gripping tool is designed to grip the first end (41) of the connecting element (4) or a projection (46) connected to the first end (41). [5] System according to claim 1, further comprising a connecting unit, wherein the connecting unit is configured to form a permanent connection between the first end (41) of the connecting element and the connecting surface (120). [6] System according to claim 5, wherein the connecting unit comprises a transducer and a sonotrode, wherein the transducer is coupled to the sonotrode and is configured to vibrate the sonotrode in order to form a permanent connection between the first end (41) of the connecting element and the connecting surface (120), and the pick-and-place unit (92) comprises a channel and a suction device, wherein the channel extends through the pick-and-place unit (92) and has at least two openings to the outside of the pick-and-place unit (92), and the suction device is coupled to a first of the at least two openings and is designed to cause the first end (41) of the connecting element (4) or a projection (46) connected to the first end (41) to be sucked towards a second of the at least two openings. [7] System according to claim 5, wherein the connecting unit comprises a transducer and a sonotrode, wherein the transducer is coupled to the sonotrode and is configured to vibrate the sonotrode to form a permanent connection between the first end (41) of the connecting element and the connecting surface (120), and the pick-and-place unit (92) comprises a gripping tool configured to grip the first end (41) of the connecting element (4) or a projection (46) connected to the first end (41). [8] System according to any one of claims 1 to 7, wherein the pattern recognition unit (90) is configured to determine the actual position of the connecting surface (120) and the actual position of the first end (41) of the connecting element (4) using a pattern recognition technique. [9] System according to claim 8, wherein the pattern recognition unit (90) has at least one camera and wherein the pattern recognition unit (90) is configured to take at least one picture of the base plate (80) and the substrate (10) arranged thereon by means of the at least one camera. [10] One procedure shows: Determining the actual position of a connection surface (120) using a pattern recognition unit (90), wherein the connection surface (120) is arranged on or above a substrate (10) of a semiconductor module and the substrate (10) is arranged on a base plate (80), Determining the actual position of a first end (41) of a connecting element (4) using the pattern recognition unit (90), wherein the connecting element (4) is attached to a housing (7) and the housing (7) is arranged on the base plate (80) such that the substrate (10) is arranged within a volume defined by the housing (7), Determining a deviation between the actual position of the first end (41) of the connecting element (4) in relation to the actual position of the connecting surface (120), and Moving a pick-and-place unit (92) to the actual position of the first end (41) determined by the pattern recognition unit (90), picking up the first end (41) of the connecting element (4) by means of the pick-and-place unit (92) and subsequently moving the first end (41) to the actual position of the connecting surface (120) as determined by the pattern recognition unit (90) by means of the pick-and-place unit (92). [11] The method of claim 10, further comprising: Forming a permanent connection between the first end (41) of the connecting element (4) and the connecting surface (120). [12] Method according to claim 11, wherein forming a permanent connection between the first end (41) of the connecting element (4) and the connecting surface (120) comprises carrying out an ultrasonic welding process.

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