Patent Description:
Power semiconductor module arrangements often include at least one semiconductor substrate arranged in a housing. A semiconductor arrangement including a plurality of controllable semiconductor elements (e.g., two IGBTs in a half-bridge configuration) is arranged on each of the at least one substrates. Each substrate usually comprises a substrate layer (e.g., a ceramic layer), a first metallization layer deposited on a first side of the substrate layer and a second metallization layer deposited on a second side of the substrate layer. The controllable semiconductor elements are mounted, for example, on the first metallization layer. The second metallization layer may optionally be attached to a base plate. The controllable semiconductor devices are usually mounted onto the semiconductor substrate by soldering or sintering techniques. An electronic board or metal sheet may be arranged in or on the same housing as the at least one substrate. The electronic board or metal sheet may form a lid of the housing, for example, or may be arranged on or below a lid of the housing on the inside or the outside of the housing. Electrical connections may be formed between the at least one semiconductor substrate and the electronic board or metal sheet. Such electrical connections should form a stable electrical connection between the at least one substrate and the electronic board or metal sheet.

Document <CIT> discloses a power module comprising: - a base region with a surface on which an electrode region is formed; - a conductor region which is arranged so that it faces the base region; and a connecting region which is connected to the electrode region and a surface of the conductor region, the surface of the conductor region facing the one surface of the electrode region, the conductor region has an opening, opposite ends of the connection area being connected to the conductor area across the opening, and a part of the connection area at a position corresponding to the opening is connected to the electrode region, the connection region being a wire or a ribbon.

Document <CIT> discloses an apparatus having a package, a wall and a lid. The package may be configured to mount a plurality of chips. Two of the chips may generate a plurality of signals in a millimeter-wave frequency range. A metal is exposed at a surface of the package between the two chips. The metal is generally connected to an electrical ground. The wall may be formed on the metal and between the two chips. The wall generally has a plurality of arches that (i) are conductive, (ii) are wire bonded to the metal and (iii) attenuate an electromagnetic coupling between the two chips at the millimeter-wave frequency. The lid may be configured to enclose the chips to form a millimeter-wave cavity.

There is a need for a power semiconductor module arrangement comprising at least one semiconductor substrate and an electronic board or metal sheet, and having stable electrical connections between the at least one semiconductor substrate and the electronic board or metal sheet such that its risk of failure is low and its lifetime is long.

A power semiconductor module arrangement includes a semiconductor substrate arranged in a housing, an electronic board or metal sheet arranged in the housing distant from the semiconductor substrate, wherein the electronic board or metal sheet is arranged in parallel to the semiconductor substrate, and at least one electrical connection, configured to electrically couple the electronic board or metal sheet to the semiconductor substrate or to one of the elements mounted thereon, wherein each of the at least one electrical connection comprises a first end and a second end, and an intermediate section extending between the first end and the second end, and wherein the first end and the second end of each electrical connection are mechanically coupled to the electronic board or metal sheet, and a middle section of the intermediate section is mechanically coupled to the semiconductor substrate or to one of the elements mounted thereon. The electronic board or metal sheet forms a cover of the housing.

A method for producing a power semiconductor module arrangement includes mounting at least one electrical connection onto an electronic board or metal sheet by connecting a first end and a second end of the electrical connection to a first side of the electronic board or metal sheet, arranging the electronic board or metal sheet with the electrical connection mounted thereon in parallel to a semiconductor substrate such that the first side of the electronic board or metal sheet faces the semiconductor substrate, the semiconductor substrate having one or more elements mounted thereon, and connecting a middle section of an intermediate section of the electrical connection to the semiconductor substrate or to one of the elements mounted thereon, wherein the intermediate section extends between the first end and the second end of the electrical connection. The electronic board or metal sheet is arranged to form a cover of the housing.

In the following detailed description, reference is made to the accompanying drawings. The drawings show specific examples in which the invention may be practiced. It is to be understood that the features and principles described with respect to the various examples may be combined with each other, unless specifically noted otherwise. In the description as well as in the claims, designations of certain elements as "first element", "second element", "third element", etc. are not to be understood as enumerative. Instead, such designations serve solely to address different "elements". That is, e.g., the existence of a "third element" does not require the existence of a "first element" and a "second element". Electrical lines and electrical connections may include metal and/or semiconductor material, and may be permanently electrically conductive (i.e., non-switchable). A semiconductor body as described herein may be made from (doped) semiconductor material and may be a semiconductor chip or be included in a semiconductor chip. A semiconductor body has electrically connecting pads and includes at least one semiconductor element with electrodes.

Referring to <FIG>, a cross-sectional view of a power semiconductor module arrangement is schematically illustrated. The power semiconductor module arrangement includes a semiconductor substrate <NUM>. The semiconductor substrate <NUM> includes a dielectric insulation layer <NUM>, a first (structured) metallization layer <NUM> attached to the dielectric insulation layer <NUM>, and a second (structured) metallization layer <NUM> attached to the dielectric insulation layer <NUM>. The dielectric insulation layer <NUM> is disposed between the first and the second metallization layer <NUM>, <NUM>. It is, however, also possible that the semiconductor substrate <NUM> only comprises a first metallization layer <NUM>, while the second metallization layer <NUM> is omitted.

Each of the first and second metallization layers <NUM>, <NUM> may consist of or include one of the following materials: copper; a copper alloy; aluminum; an aluminum alloy; any other metal or alloy that remains solid during the operation of the power semiconductor module arrangement. The semiconductor substrate <NUM> may be a ceramic substrate, that is, a substrate in which the dielectric insulation layer <NUM> is a ceramic, e.g., a thin ceramic layer. The ceramic may consist of or include one of the following materials: aluminum oxide; aluminum nitride; zirconium oxide; silicon nitride; boron nitride; or any other dielectric ceramic. For example, the dielectric insulation layer <NUM> may consist of or include one of the following materials: Al<NUM>O<NUM>, AlN, SiC, BeO or Si<NUM>N<NUM>. For instance, the substrate <NUM> may, e.g., be a Direct Copper Bonding (DCB) substrate, a Direct Aluminum Bonding (DAB) substrate, or an Active Metal Brazing (AMB) substrate. Further, the substrate <NUM> may be an Insulated Metal Substrate (IMS). An Insulated Metal Substrate generally comprises a dielectric insulation layer <NUM> comprising (filled) materials such as epoxy resin or polyimide, for example. The material of the dielectric insulation layer <NUM> may be filled with ceramic particles, for example. Such particles may comprise, e.g., Si<NUM>O, Al<NUM>O<NUM>, AlN, or BN and may have a diameter of between about <NUM> and about <NUM>. According to one example, an integrated semiconductor substrate is embedded in an AlSiC/magnesium base plate. The substrate <NUM> may also be a conventional printed circuit board (PCB) having a non-ceramic dielectric insulation layer <NUM>. For instance, a non-ceramic dielectric insulation layer <NUM> may consist of or include a cured resin.

The semiconductor substrate <NUM> is arranged in a housing <NUM>. In the arrangement illustrated in <FIG>, the semiconductor substrate <NUM> forms a ground surface of the housing <NUM>, while the housing <NUM> itself solely comprises sidewalls. This is, however, only an example. It is also possible that the housing <NUM> further comprises a ground surface and/or a cover or lid and that the semiconductor substrate <NUM> is arranged inside the housing <NUM>.

One or more semiconductor bodies <NUM> may be arranged on the semiconductor substrate <NUM>. Each of the semiconductor bodies <NUM> arranged on the at least one semiconductor substrate <NUM> may include 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), and/or any other suitable semiconductor element. The one or more semiconductor bodies <NUM> may form a semiconductor arrangement on the semiconductor substrate <NUM>. In <FIG>, only two semiconductor bodies <NUM> are exemplarily illustrated.

The second metallization layer <NUM> of the semiconductor substrate <NUM> in <FIG> is a continuous layer. The first metallization layer <NUM> is a structured layer in the arrangement illustrated in <FIG>. "Structured layer" means that the first metallization layer <NUM> is not a continuous layer, but includes recesses between different sections of the layer. Such recesses are schematically illustrated in <FIG>. The first metallization layer <NUM> in this arrangement includes three different sections. Different semiconductor bodies <NUM> may be mounted on the same or to different sections of the first metallization layer <NUM>. Different sections of the first metallization layer may have no electrical connection or may be electrically connected to one or more other sections using first electrical connections <NUM> such as, e.g., bonding wires, bonding ribbons, ultrasonic welding terminals or joints, or soldered clip connections. First electrical connections <NUM> may also include connection plates or conductor rails, for example, to name just a few examples. The one or more semiconductor bodies <NUM> may be electrically and mechanically connected to the semiconductor substrate <NUM> by an electrically conductive connection layer <NUM>. Such an electrically conductive connection layer <NUM> may be a solder layer, a layer of an electrically conductive adhesive, or a layer of a sintered metal powder, e.g., silver, for example.

The power semiconductor module arrangement illustrated in <FIG> further includes first terminal elements <NUM>. The first terminal elements <NUM> are electrically connected to the first metallization layer <NUM> and provide an electrical connection between the semiconductor substrate <NUM> and the outside of the housing <NUM>. The first terminal elements <NUM> may be electrically connected to the first metallization layer <NUM> with a first end, while a second end of the first terminal elements <NUM> protrudes out of the housing <NUM>. The first terminal elements <NUM> may be electrically contacted from the outside at their second end.

For example, the second ends of the first terminal elements <NUM> may be mechanically and electrically connected to an electronic board, e.g., a printed circuit board (PCB) having a dielectric insulation layer, or to a metal sheet <NUM>. A metal sheet could be electrically coupled to a certain electrical potential, for example. For instance, a non-ceramic dielectric insulation layer may consist of or include a cured resin. The electronic board or metal sheet <NUM> forms a cover of the housing and may comprise through holes. The first terminal elements <NUM> may be inserted into the through holes of the electronic board or metal sheet <NUM>. An electronic board <NUM> may comprise conducting tracks (not specifically illustrated) arranged on the dielectric insulation layer and a terminal element <NUM> may be electrically coupled to one or more other first terminal elements <NUM> by means of one or more such conducting tracks of the electronic board <NUM>. A metal sheet generally is also electrically conducting. In this way, an electrical connection may be provided between different sections of the first metallization layer <NUM>, between different semiconductor bodies <NUM>, and/or between any other components that are arranged on the semiconductor substrate <NUM>. The first terminal elements <NUM> may be soldered to the electronic board or metal sheet <NUM>, for example, to provide for a permanent and solid connection. This, however, is only an example.

Alternatively or additionally, the power semiconductor module arrangement may comprise second terminal elements <NUM>. Such second terminal elements <NUM> may be electrically and mechanically connected to the electronic board or metal sheet <NUM> with a first end, while a second end of the second terminal elements <NUM> protrudes from the electronic board or metal sheet <NUM>. Second terminal elements <NUM> allow to electrically contact the power semiconductor module arrangement from outside the housing <NUM>. However, contrary to the first terminal elements <NUM>, the second terminal elements do not extend through the electronic board or metal sheet <NUM> towards the semiconductor substrate <NUM>. The second terminal elements <NUM> terminate on the electronic board or metal sheet <NUM>. A second terminal element <NUM> may be electrically coupled to a conductor track of the electronic board or to the metal sheet <NUM>, for example. An electrical connection between the respective conductor track or the metal sheet and the semiconductor substrate <NUM> may be established by means of one or more of the first terminal elements or by one or more second electrical connections <NUM>, as will be described in the following.

The power semiconductor module arrangement alternatively or additionally may include second electrical connections <NUM>. Such second electrical connections <NUM> may also provide an electrical connection between the semiconductor substrate <NUM> and the electronic board or metal sheet <NUM>, and may or may not protrude through the electronic board or metal sheet <NUM> to the outside of the housing <NUM>. The second electrical connection <NUM> in <FIG> may comprise a bonding wire or bonding ribbon, for example. A first end of a bonding wire or ribbon is soldered (or welded) to the semiconductor substrate <NUM>, and a second end of a bonding wire or ribbon is soldered (or welded) to the electronic board or metal sheet <NUM>. In order to form such a connection <NUM> that does not protrude through the electronic board or metal sheet <NUM> to the outside of the housing <NUM>, a spring contact may be used, for example, which is pre-assembled and soldered (or welded) to the semiconductor substrate <NUM> afterwards. If the second electrical connection <NUM> protrudes through the electronic board or metal sheet <NUM> to the outside of the housing <NUM>, the second electrical connection <NUM> may extend through an opening in the electronic board or metal sheet <NUM> to the outside of the housing <NUM>, for example.

The housing <NUM> may be at least partly filled with a sealing resin <NUM>. The sealing resin <NUM> may include a (filled) epoxy resin, silicone gel or other resin materials, for example. The sealing resin <NUM> is configured to seal the components of the power semiconductor module such as the semiconductor substrate <NUM>, in particular the metal patterns formed by the first metallization layer <NUM>, the semiconductor bodies <NUM>, the first electrical connections <NUM>, the first terminal elements <NUM>, and the second electrical connections <NUM>, to provide for insulation and protection of the devices. For example, the sealing resin <NUM> may protect the components from certain environmental conditions and from mechanical damage. The sealing resin <NUM> may at least partly fill the interior of the housing <NUM>, thereby covering the components and electrical connections that are arranged on the semiconductor substrate <NUM>. The first terminal elements <NUM> and the second electrical connections <NUM> may be partly embedded in the sealing resin <NUM>. At least the second ends of the first terminal elements <NUM> and of the second electrical connections <NUM>, however, are not covered by the sealing resin <NUM> and protrude from the sealing resin <NUM> to the electronic board or metal sheet <NUM>.

The power semiconductor module may further include a base plate <NUM>. The semiconductor substrate <NUM> may be connected to the base plate <NUM> via a connection layer (not illustrated). Such a connection layer may be a solder layer, a layer of an adhesive, or a layer of a sintered metal powder, e.g., silver, for example.

<FIG> schematically illustrates a power semiconductor arrangement with a base plate <NUM>. However, it is also possible that the base plate <NUM> be omitted. In such cases, the semiconductor substrate <NUM> may form a ground surface of the housing <NUM>, for example. The semiconductor substrate <NUM>, instead of on a base plate <NUM>, may be arranged on a heat sink, for example. Generally, if the power semiconductor module arrangement comprises a base plate <NUM>, the base plate <NUM> may also further be arranged on a heat sink (heat sink not specifically illustrated) such that the base plate <NUM> is arranged between the heat sink and the semiconductor substrate <NUM>, for example. In some power semiconductor module arrangements, more than one semiconductor substrate <NUM> is arranged on a single base plate <NUM>. Irrespective of the number of semiconductor substrates <NUM> that are mounted on the base plate <NUM>, the base plate <NUM> may form a ground surface of the housing <NUM>, for example. Semiconductor bodies <NUM> may be arranged on one or more of a plurality of semiconductor substrates <NUM>.

When producing the power semiconductor module of <FIG>, generally the one or more semiconductor substrates <NUM> are assembled first. That is, the first metallization layer <NUM> and, optionally, the second metallization layer <NUM> are formed on the dielectric insulation layer <NUM>, and one or more semiconductor bodies <NUM> are arranged on the semiconductor substrate <NUM>. Assembly of the one or more semiconductor substrates <NUM> further comprises forming the first electrical connections <NUM> on the semiconductor substrates <NUM>. Any other elements of a power semiconductor module arrangement may be mounted onto the semiconductor substrate <NUM> as well during the assembly process. Once the at least one semiconductor substrate <NUM> is fully assembled, it may be arranged in a housing <NUM>. An electronic board having conductor tracks formed thereon or a metal sheet <NUM> may then be provided. During or shortly before mounting the electronic board or metal sheet <NUM> onto the housing <NUM>, the second electrical connections <NUM> may be formed. That is, a first end of a second electrical connection <NUM> (e.g., bonding wire or ribbon) may be mounted onto one of the at least one semiconductor substrate <NUM>. The electronic board or metal sheet <NUM> may then be arranged close to the housing <NUM>, but not yet fully covering the housing <NUM>, in order to be able to couple the second end of the second electrical connection <NUM> to the electronic board or metal sheet <NUM>. Once all necessary second electrical connections <NUM> have been formed, the electronic board or metal sheet <NUM> may be mounted and fixed onto the housing <NUM>, thereby forming a cover of the housing <NUM>, for example.

Forming the second electrical connections <NUM>, in particular forming a connection between the second ends and the electronic board or metal sheet <NUM> may be challenging. The electronic board or metal sheet <NUM> needs to be firmly held in place and prevented from vibrating. There is a risk that second electrical connections <NUM> are defective or that second electrical connections <NUM> are torn off during the process of mounting the electronic board or metal sheet <NUM> onto the housing <NUM>. Therefore, second electrical connections <NUM> that electrically couple a semiconductor substrate <NUM> to an electronic board or metal sheet <NUM> in the described manner are often designed redundantly. That is, two or more second electrical connections <NUM> may be used to form a single connection. In this way, the number of defects may be reduced and the reliability of the power semiconductor module arrangement may be increased. On the other hand, however, the overall costs for the power semiconductor module increase, as more electrical connections are required. This results in an increase of material usage, as well as in increased space requirements.

Now referring to <FIG>, a power semiconductor module arrangement according to one example is schematically illustrated. The power semiconductor module arrangement essentially corresponds to the arrangement illustrated in <FIG>. First and second terminal elements <NUM>, <NUM>, however, are not specifically illustrated in <FIG>. The at least one second electrical connection <NUM> differs from the second electrical connection <NUM> as discussed with respect to <FIG> above. In <FIG>, one second electrical connection <NUM> is exemplarily illustrated. However, a power semiconductor module arrangement may comprise a plurality of second electrical connections <NUM> in order to electrically couple various sections of the first metallization layer <NUM> and various conducting paths of the electronic board <NUM>, or various sections of the first metallization layer <NUM> and the metal sheet <NUM> to each other.

The second electrical connection <NUM> illustrated in <FIG> comprises a first end <NUM> that is mechanically coupled to the electronic board or metal sheet <NUM>, and a second end <NUM> that is mechanically coupled to the electronic board or metal sheet <NUM> distant to the first end <NUM>. The first end <NUM> may be electrically coupled to a first conductor track of an electronic board <NUM>, for example. The second end <NUM> may be electrically coupled to the first or to a second conductor track of the electronic board <NUM>, for example. The different first and the second conductor tracks, however, may be coupled to the same electrical potential. The second electrical connection <NUM> further comprises an intermediate section extending between the first end <NUM> and the second end <NUM>. The intermediate section is mechanically coupled to the semiconductor substrate <NUM>. In particular, a middle section <NUM> of the intermediate section may be mechanically coupled to the semiconductor substrate <NUM>. A middle section <NUM> of the intermediate section is a section that is arranged essentially centrally between the first end <NUM> and the second end <NUM>. That is, a distance from the middle section <NUM> to the first end <NUM> essentially equals a distance between the middle section <NUM> and the second end <NUM>.

The intermediate section of the second electrical connection <NUM> may form an arc, bridge or loop between the first end <NUM> and the second end <NUM>. That is, the intermediate section extends from the first end <NUM> and the second end <NUM> towards the semiconductor substrate <NUM>, when the power semiconductor module arrangement is fully assembled. The middle section <NUM> of the intermediate section may form the topmost point (or undermost point) of the arc, bridge or loop. That is, the middle section <NUM> may form that part of the intermediate section that is arranged the farthest away from the electronic board or metal sheet <NUM> and the closest to the semiconductor substrate <NUM> when the power semiconductor module arrangement is fully assembled. The arc, bridge or loop formed by the intermediate section may have an offset that may give way when connecting the middle section <NUM> to the semiconductor substrate <NUM>. In this way, the risk of breakage or damage to the second electrical connection <NUM>, in particular the risk of unintentionally tearing off the first end <NUM> and the second end <NUM> from the electronic board or metal sheet <NUM>, may be greatly reduced. The arc, bridge or loop formed by the intermediate section may have a rounded form, as is schematically illustrated in <FIG>. However, generally it is also possible that the arc, bridge or loop has an angular form. That is, the intermediate section may have comparably sharp corners, in particular near the middle section <NUM>. Generally, the intermediate section may have any suitable form.

The second electrical connection <NUM> illustrated in <FIG> and described above is a very stable connection. The second electrical connection <NUM> comprises two points of contact connecting the second electrical connection <NUM> to the electronic board or metal sheet <NUM>, and a further point of contact connecting the second electrical connection <NUM> to the semiconductor substrate <NUM>. This makes a redundant design superfluous. That is, there is no need to provide two identical second electrical connections <NUM> for the same electrical interconnection between the semiconductor substrate <NUM> and the electronic board or metal sheet <NUM>. The overall costs as well as the space requirements and therefore the size of the power semiconductor module arrangement of the example illustrated in <FIG>, therefore, are reduced as compared to the arrangement as illustrated in <FIG>, which generally requires a redundant design in order to reduce the risk of failures.

The second electrical connection <NUM> may comprise a bonding wire or a bonding ribbon. Bonding wires generally have a round or rounded (e.g., oval) cross section, while bonding ribbons generally have an angular (e.g., square or rectangular) cross section. Bonding wires may have diameters of between <NUM> and <NUM> (thin bonding wires), or between <NUM> and <NUM> (thick bonding wires), for example. Any other diameters, however, are also possible. The diameter of a bonding wire may depend on the material that is used to form the bonding wire, for example. The diameter of a bonding wire may further depend on the application the power semiconductor module arrangement is to be used in and the current range of the specific application, for example. Dimensions of bonding ribbons may be in the range of <NUM> x <NUM> (width x thickness) up to <NUM> x <NUM>, for example. Any other dimensions, however, are also possible.

The at least one second electrical connection <NUM> may comprise at least one of Al (aluminum), AlMg (magnesium alloyed aluminum), Cu (copper), and Au (gold), for example. That is, aluminum, aluminum alloyed, copper or gold bonding wires or ribbons may be used to form the second electrical connections <NUM>, for example. According to one example, the at least one second electrical connection <NUM> comprises an aluminum cladded copper wire.

A mechanical connection between the first and second ends <NUM>, <NUM> and the electronic board or metal sheet <NUM>, respectively, may be a bond connection or a welded connection, for example. That is, the connections may be formed by means of a bonding process or a welding process, for example. According to one example, an ultrasonic bonding or welding process is used in order to form the connections between the first and second ends <NUM>, <NUM> and the electronic board or metal sheet <NUM>. The same applies for the mechanical connection between the middle section <NUM> of the intermediate section of the second electrical connection <NUM> and the semiconductor substrate <NUM>. This connection between the middle section <NUM> and the semiconductor substrate <NUM> may also be a bond connection or a welded connection, for example.

In the example illustrated in <FIG>, the middle section <NUM> is mechanically and electrically coupled to the semiconductor substrate <NUM>. However, it is also possible that the middle section <NUM> is mechanically and electronically coupled to other components of the power semiconductor module arrangement. As is illustrated in the example of <FIG>, it is also possible to mechanically and electrically couple the middle section <NUM> to one of the semiconductor bodies <NUM>, for example. The middle section <NUM> alternatively may be mechanically and electrically coupled to any other suitable components of the power semiconductor module arrangement. It is possible to combine the different options within one and the same power semiconductor module arrangement. That is, if the power semiconductor module arrangement comprises more than one second electrical connections <NUM>, a first group of second electrical connections <NUM> may be mechanically end electrically coupled to the semiconductor substrate <NUM>, while another group of second electrical connections <NUM> may be mechanically and electrically coupled to a semiconductor body <NUM> or any other component of the power semiconductor module arrangement. Each group of second electrical connections <NUM> may comprise one or more of a plurality of second electrical connections <NUM>.

Now referring to <FIG>, a method for forming an electrical connection according to one example is exemplarily illustrated. In a first step (<FIG>), a second electrical connection <NUM> may be mounted onto an electronic board or metal sheet <NUM>. That is, a first end <NUM> and a second end <NUM> of an electrical connection <NUM> may be mechanically (and electrically) coupled to the electronic board or metal sheet <NUM>. The connections between the first and second ends <NUM>, <NUM> and the electronic board or metal sheet <NUM> may be formed by means of a bonding, a welding, or an ultrasonic bonding or welding process, for example. Such processes are generally known and will not be described in further detail herein. Mounting the second electrical connection <NUM> onto the electronic board or metal sheet <NUM> may be similar to arranging a conventional bonding wire or bonding ribbon on a printed circuit board, a metal sheet or a semiconductor substrate, for example. In this way, a very stable connection may be formed between the second electrical connection <NUM> and the electronic board or metal sheet <NUM>. The second electrical connection <NUM> may be arranged on a first side of the electronic board or metal sheet <NUM>. During the mounting process (<FIG>), the first side of the electronic board or metal sheet <NUM> may be a top side of the electronic board or metal sheet <NUM>. That is, the first side may be a side which faces the bonding or welding tool, for example.

Now referring to <FIG>, the electronic board or metal sheet <NUM> with the second electrical connection <NUM> mounted thereon may be arranged above a semiconductor substrate <NUM>. That is, the electronic board or metal sheet <NUM> may be arranged distant from and in parallel to a semiconductor substrate <NUM>. In <FIG> and <FIG>, the semiconductor substrate <NUM> is only schematically illustrated. In this simplified representation, the metallization layers <NUM>, <NUM> as well as any semiconductor bodies <NUM> or first electrical connections <NUM> or any other elements are omitted for convenience only. When the electronic board or metal sheet <NUM> is arranged above the semiconductor substrate <NUM>, the semiconductor substrate <NUM> may already be fully assembled. That is, all semiconductor bodies <NUM> and first electrical connections <NUM> that are necessary for the specific application may already be arranged on the semiconductor substrate <NUM>. When arranging the electronic board or metal sheet <NUM> above the semiconductor substrate <NUM>, the first side of the electronic board or metal sheet <NUM> may face the semiconductor substrate <NUM>. That is, the first side of the electronic board or metal sheet <NUM> may face a first side of the semiconductor substrate <NUM>, wherein the first side of the semiconductor substrate <NUM> is a side on which at least one semiconductor body <NUM> is arranged (see, e.g., <FIG> and <FIG>).

A distance d1 between the electronic board or metal sheet <NUM> and the semiconductor substrate <NUM> (or between the electronic board or metal sheet <NUM> and the semiconductor body <NUM> or any other component, if the middle section <NUM> is mechanically coupled to one of the semiconductor bodies <NUM> or any of the other components), may equal or be slightly less than a height d2 of the arc, bridge or loop formed by the intermediate section of the second electrical connection <NUM>. The height d2 of the arc, bridge or loop may equal a distance between the middle section <NUM> and the electronic board or metal sheet <NUM> (see <FIG>). That is, when arranging the electronic board or metal sheet <NUM> with the second electrical connection <NUM> mounted thereon above the semiconductor substrate <NUM>, the middle section <NUM> of the second electronic connection <NUM> loosely contacts the semiconductor substrate <NUM>, the semiconductor body <NUM>, or any other component of the power semiconductor module arrangement.

The electronic board or metal sheet <NUM> comprises a though hole <NUM>. The first end <NUM> of the second electronic connection <NUM> is arranged on a first side of the through hole <NUM>, and the second end <NUM> of the second electronic connection <NUM> is arranged on a second side of the through hole <NUM>, wherein the second side is opposite to the first side. In this way, the intermediate section of the second electronic connection <NUM> extends over the through hole <NUM>. A connection tool <NUM> (e.g., bonding or welding tool) may be inserted through the through hole <NUM> and may press the middle section <NUM> onto the semiconductor substrate <NUM>, semiconductor body <NUM> or other component, in order to form a connection between the middle section <NUM> and the semiconductor substrate <NUM>, semiconductor body <NUM> or other component (<FIG>). While pressing the middle section <NUM> onto the semiconductor substrate <NUM>, semiconductor body <NUM> or other component, heat may be applied. It is also possible to perform an ultrasonic process, wherein the connection tool <NUM> vibrates at a certain frequency. The through hole <NUM> allows an easy access of the connection tool <NUM> towards the middle section <NUM>. In this way, a very stable connection may be formed between the second electrical connection <NUM> and the semiconductor substrate <NUM>, semiconductor body <NUM> or other component in an easy and convenient way even if the electronic board or metal sheet <NUM> is already arranged in its final mounted position. That is, the electronic board or metal sheet <NUM> remains in its position after forming the connections between the middle sections <NUM> and the semiconductor substrate <NUM>, semiconductor body <NUM>, or other component.

If more than one second electrical connection <NUM> is arranged on the electronic board or metal sheet <NUM>, the electronic board or metal sheet <NUM> may comprise a plurality of through holes <NUM>. The number of through holes <NUM> may be equal to or greater than the number of second electrical connections <NUM>. That is, each second electrical connection <NUM> may be arranged on the electronic board or metal sheet <NUM> such that its middle section <NUM> extends over a different one of the through holes <NUM>. This allows to mechanically couple each of the second electrical connections <NUM> to the semiconductor substrate <NUM>, semiconductor body <NUM>, or other component after arranging the electronic board or metal sheet <NUM> above the semiconductor substrate <NUM>. If the number of through holes <NUM> is greater than the number of second electrical connections <NUM>, any additional through holes <NUM> may serve different purposes, for example. For example, lead frames <NUM> may extend through any additional through holes <NUM>. This, however, is optional.

A method for producing a power semiconductor module arrangement may comprise assembling the semiconductor substrate <NUM> before arranging the electronic board or metal sheet <NUM> above the semiconductor substrate <NUM>. The step of assembling the semiconductor substrate <NUM> has already been discussed exemplarily above. A method for producing a power semiconductor module arrangement may further comprise arranging the semiconductor substrate <NUM> in a housing <NUM>. A housing <NUM> is not illustrated in the example of <FIG>. The semiconductor substrate <NUM> may be fully assembled when it is arranged in the housing <NUM>, for example. The electronic board or metal sheet <NUM> may then be arranged in or on the housing <NUM>. For example, the electronic board or metal sheet <NUM> may be arranged on the sidewalls of the housing <NUM>. A height of the sidewalls in this case may define the distance d1 between the electronic board or metal sheet <NUM> and the semiconductor substrate <NUM>. The electronic board or metal sheet <NUM> may be fixed to the sidewalls of the housing <NUM> in any suitable way (e.g., insert, gluing, screwing or clamping). It is also possible that the sidewalls of the housing <NUM> comprise projections on the inside of the housing <NUM>. The electronic board or metal sheet <NUM> may be arranged inside the housing <NUM>, resting on such projections, for example. In this way, the electronic board or metal sheet <NUM> may be precisely aligned with respect to the layout of the semiconductor substrate <NUM>. An additional adhesion or clamping in order to fix the electronic board or metal sheet <NUM> in its position may not even be necessary in many cases. The mechanical (and electrical) connections between the middle sections <NUM> of the at least one second electrical connection <NUM> and the semiconductor substrate <NUM>, semiconductor body <NUM> or other component may then be easily formed by inserting the connection tool <NUM> through the respective through holes <NUM>. According to one example, the electronic board or metal sheet <NUM> forms a cover of the housing <NUM>. According to another example (not specifically illustrated), an additional cover may be mounted on the sidewalls such that the electronic board or metal sheet <NUM> is arranged inside the housing <NUM> and is not directly accessible from the outside of the housing.

Generally, second electrical connections <NUM>, as have been described with respect to <FIG> and <FIG> above, allow the usage of the power semiconductor module arrangement for applications having a voltage class of even above <NUM>. The risk of failures is reduced as compared to conventional arrangements.

Now referring to <FIG>, a second electrical connection <NUM> that is mounted on an electronic board or metal sheet <NUM> is illustrated in greater detail. As has been explained above, the second electrical connection <NUM> comprises a first end <NUM> that is coupled to the electronic board or metal sheet <NUM>. The second electrical connection <NUM> further comprises a second end <NUM> that is coupled to the electronic board or metal sheet <NUM>. The first and second ends <NUM>, <NUM> are arranged on opposite sides of a though hole <NUM> on the same side of the electronic board or metal sheet <NUM>. A distance e between the first end <NUM> and the second end <NUM> may be larger than a width a of the through hole <NUM> in the same direction. That is, the first and second ends <NUM>, <NUM> may not directly adjoin the though hole <NUM>. Instead, the first end and the second end <NUM>, <NUM> each are arranged at a certain distance from the outer diameter of the through hole <NUM>. This distance may depend on the dimensions of the second electrical connection <NUM> as well as on the distance between the electronic board or metal sheet <NUM> and the semiconductor substrate <NUM>, semiconductor body <NUM> or other component in the fully assembled power semiconductor module arrangement.

The intermediate section of the second electronic connection <NUM> extends from the electronic board or metal sheet <NUM> and forms an arc, bridge or loop that extends from the first end <NUM> over the through hole <NUM> to the second end <NUM>. The middle section <NUM> is arranged directly above the through hole <NUM> to be accessible by a connection tool <NUM>. The dimensions a of the through hole <NUM> generally depend on the size of the connection tool <NUM> that is used to form the connection between the middle section <NUM> and the semiconductor substrate <NUM>, semiconductor body <NUM>, or other component. The through hole <NUM> is large enough in order to allow the connection tool <NUM> to easily access the middle section <NUM>. Even further, if an ultrasonic bonding or welding process is used to form the connection between the middle section <NUM> and the semiconductor substrate <NUM>, semiconductor body or other component, the dimensions a of the through hole <NUM> may further allow vibrations of the connection tool <NUM>. That is, even when vibrating during the connection process, the connection tool <NUM> may not touch the electronic board or metal sheet <NUM>. Therefore, no vibrations may be transferred from the connection tool <NUM> to the electronic board or metal sheet <NUM>.

Claim 1:
A power semiconductor module arrangement comprising:
a semiconductor substrate (<NUM>) arranged in a housing (<NUM>), the semiconductor substrate (<NUM>) having one or more elements mounted thereon;
an electronic board or metal sheet (<NUM>) arranged in the housing (<NUM>) distant from the semiconductor substrate (<NUM>), wherein the electronic board or metal sheet (<NUM>) is arranged in parallel to the semiconductor substrate (<NUM>); and
at least one electrical connection (<NUM>), configured to electrically couple the electronic board or metal sheet (<NUM>) to the semiconductor substrate (<NUM>) or to one of the elements mounted thereon, wherein each of the at least one electrical connection (<NUM>) comprises a first end (<NUM>) and a second end (<NUM>), and an intermediate section extending between the first end (<NUM>) and the second end (<NUM>), and wherein the first end (<NUM>) and the second end (<NUM>) of each electrical connection (<NUM>) are mechanically coupled to the electronic board or metal sheet (<NUM>), and a middle section (<NUM>) of the intermediate section is mechanically coupled to the semiconductor substrate (<NUM>) or to one of the elements mounted thereon, characterized in that the electronic board or metal sheet (<NUM>) forms a cover of the housing (<NUM>).