Patent Description:
Power semiconductor module arrangements often include a substrate within a housing. The 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, optionally, a second metallization layer deposited on a second side of the substrate layer. A semiconductor arrangement including one or more controllable semiconductor elements (e.g., two IGBTs in a half-bridge configuration) may be arranged on the substrate. One or more contact elements, which allow for contacting such a semiconductor arrangement from outside the housing, are usually provided. A printed circuit board may be arranged outside of the housing, which contacts the one or more contact elements. Different contact elements may be electrically coupled to each other by means of conducting tracks on the printed circuit board, for example. The housing may comprise protrusions on its outside. Through holes may be provided in the protrusions such that the housing can be mounted on a heat sink or a base plate by means of screws that are inserted through the through holes and screwed into respective boreholes provided in the heat sink or base plate. The printed circuit board provided outside of the housing, however, impedes the insertion of the screws into the boreholes and the fastening of the screws by means of suitable tools. Usually, large through holes have to be provided in the printed circuit board in order to be able to insert the screws into the boreholes. Therefore, valuable space on the printed circuit board which is needed for forming conducting tracks thereon is consumed by the through holes.

Document <CIT> discloses a mounting structure for a power module. In the heat sink, screw holes having female screw threads into which power module fixing screws are screwed are formed so as to penetrate a power module mounting surface of the heat sink and heat radiation fins. The power module fixing screw is constructed such that, to mount the power module on the heat sink, the screw head of the power module fixing screw is tightened from the printed circuit board side with a tool and that, to remove the power module from the heat sink, the power module fixing screw is loosened with the tool from the heat radiation fin side on the opposite side of the screw head.

Document <CIT> discloses a power semiconductor device module including a metal baseplate and a plastic housing that together form a tray. Power electronics are disposed in the tray. A plastic cap covers the tray. Electrical press-fit terminals are disposed along the periphery of the tray. Each electrical terminal has a press-fit pin portion that sticks up through a hole in the cap. In addition, the module includes four mechanical corner press-fit anchors disposed outside the tray. One end of each anchor is embedded into the housing. The other end is an upwardly extending press-fit pin portion. The module is manufactured and sold with the press-fit pin portions of the electrical terminals and the mechanical corner anchors unattached to any printed circuit board (PCB). The mechanical anchors help to secure the module to a PCB. Due to the anchors, screws or bolts are not needed to hold the module to the PCB.

Document <CIT> discloses a power device package coupled to a heat sink using a bolt and a semiconductor package mold for fabricating the same. The power device package includes: a substrate; at least one power device mounted on the substrate; a mold member sealing the substrate and the power device; and at least one bushing member fixed to the mold member to provide a through hole for a bolt member for coupling a heat sink to the mold member.

Document <CIT> discloses an assembled structure including a power semiconductor device, a first insulating member, a heat sink and a fastening element. The power semiconductor device has a first perforation. The first insulating member includes a first opening and a second opening corresponding to the first perforation and a receiving portion between the first opening and a second opening. The fastening element includes a head portion and a body portion. The body portion is penetrated through the first opening, the receiving portion, the second opening and the first perforation such that the power semiconductor device is fastened onto the heat sink. The head portion is received in the receiving portion so as to isolate the head portion of the fastening element from adjacent electronic components.

There is a need for a housing that can be easily mounted on a heat sink or base plate, while still allowing to provide sufficient space on a printed circuit board outside of the housing.

An arrangement includes a housing and a printed circuit board arranged vertically above the housing, wherein the housing includes sidewalls, at least one protrusion attached to the sidewalls and arranged on the outside of the housing at a lower end of the housing distant from the printed circuit board, wherein a plurality of first through holes are provided in the at least one protrusion, a plurality of holding devices, wherein each holding device is arranged inside one of the first through holes and/or between the printed circuit board and one of the first through holes, and a plurality of fastening elements configured to attach the housing to a heat sink or base plate, wherein each of the plurality of holding devices is configured to clamp a different one of the fastening elements such that the fastening elements are secured in defined positions, and to align each of the fastening elements with a different one of the first through holes, the printed circuit board includes a plurality of second through holes, wherein each of the second through holes is arranged vertically above and aligned with a different one of the plurality of fastening elements, a diameter of each of the second through holes is less than the largest diameter of the respective fastening element, and when a defined force that is greater than a holding force of the respective holding device is exerted on the fastening elements by means of a tool passing through the respective second through holes, the fastening elements are configured to move vertically through the respective first through holes in a direction away from the printed circuit board.

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". A semiconductor body as described herein may be made from (doped) semiconductor material and may be a semiconductor chip or may 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 <NUM> is illustrated. The power semiconductor module arrangement <NUM> includes a housing <NUM> and a substrate <NUM>. The substrate <NUM> includes a dielectric insulation layer <NUM>, a (structured) first metallization layer <NUM> attached to the dielectric insulation layer <NUM>, and a (structured) second metallization layer <NUM> attached to the dielectric insulation layer <NUM>. The dielectric insulation layer <NUM> is disposed between the first and second metallization layers <NUM>, <NUM>.

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 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. Alternatively, the dielectric insulation layer <NUM> may consist of an organic compound and include one or more of the following materials: Al<NUM>O<NUM>, AlN, SiC, BeO, BN, 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., SiO<NUM>, Al<NUM>O<NUM>, AlN, SiN or BN and may have a diameter of between about <NUM> and about <NUM>. 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 substrate <NUM> is arranged in a housing <NUM>. The housing <NUM> comprises sidewalls and, optionally, a cover. The substrate <NUM> and the housing <NUM> may be mounted on a heat sink or a base plate <NUM>. The heat sink or base plate <NUM> may form a bottom of the housing <NUM>, as is schematically illustrated in <FIG>. This, however, is only an example. The housing <NUM> may also comprise a bottom that, when the housing <NUM> is arranged on the heat sink or base plate <NUM>, is arranged between the substrate <NUM> and the heat sink or base plate <NUM>. In some power semiconductor module arrangements <NUM>, more than one substrate <NUM> is arranged within the same housing <NUM>.

One or more semiconductor bodies <NUM> may be arranged on the at least one substrate <NUM>. Each of the semiconductor bodies <NUM> arranged on the at least one 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), or any other suitable semiconductor element.

The one or more semiconductor bodies <NUM> may form a semiconductor arrangement on the substrate <NUM>. In <FIG>, only two semiconductor bodies <NUM> are exemplarily illustrated. The second metallization layer <NUM> of the substrate <NUM> in <FIG> is a continuous layer. According to another example, the second metallization layer <NUM> may be a structured layer. According to other examples, the second metallization layer <NUM> may also be omitted. The first metallization layer <NUM> is a structured layer in the example illustrated in <FIG>. "Structured layer" in this context means that the respective metallization layer 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 example includes three different sections. Different semiconductor bodies <NUM> may be mounted to 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 electrical connections <NUM> such as, e.g., bonding wires. Semiconductor bodies <NUM> may be electrically connected to each other or to the first metallization layer <NUM> using electrical connections <NUM>, for example. Electrical connections <NUM>, instead of bonding wires, may also include bonding ribbons, 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 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., a sintered silver (Ag) powder, for example.

The power semiconductor module arrangement <NUM> illustrated in <FIG> further includes terminal elements <NUM>. The terminal elements <NUM> are electrically connected to the first metallization layer <NUM> and provide an electrical connection between the inside and the outside of the housing <NUM>. The terminal elements <NUM> may be electrically connected to the first metallization layer <NUM> with a first end, while a second end <NUM> of the terminal elements <NUM> protrudes out of the housing <NUM>. The terminal elements <NUM> may be electrically contacted from the outside at their second end <NUM>. Such terminal elements <NUM>, however, are only an example. The components inside the housing <NUM> may be electrically contacted from outside the housing <NUM> in any other suitable way. For example, terminal elements <NUM> may be arranged centrally on the substrate <NUM> or even closer to or adjacent to the sidewalls of the housing <NUM>. It is also possible that one or more terminal elements <NUM> protrude vertically or horizontally through the sidewalls of the housing <NUM>. The first end of a terminal element <NUM> may be electrically and mechanically connected to the substrate <NUM> by an electrically conductive connection layer, for example (not explicitly illustrated in <FIG>). Such an electrically conductive connection layer may be a solder layer, a layer of an electrically conductive adhesive, or a layer of a sintered metal powder, e.g., a sintered silver (Ag) powder, for example. The first end of a terminal element <NUM> may also be electrically coupled to the substrate <NUM> via one or more electrical connections <NUM>, for example. The second ends <NUM> of the terminal elements <NUM> may be mechanically and electrically connected to a printed circuit board <NUM>. Conductor tracks (not specifically illustrated) may be provided on the printed circuit board <NUM>, in order to electrically couple different ones of the terminal elements <NUM> with each other or to any other components that may be arranged on the printed circuit board <NUM>. Such conductor tracks may comprise any suitable electrically conducting material such as, e.g., copper. According to one example, one or more terminal elements <NUM> are implemented as bonding wires.

The power semiconductor module arrangement <NUM> generally further includes an encapsulant <NUM>. The encapsulant <NUM> may consist of or include a silicone gel or may be a rigid molding compound, for example. The encapsulant <NUM> may at least partly fill the interior of the housing <NUM>, thereby covering the components and electrical connections that are arranged on the substrate <NUM>. The terminal elements <NUM> may be partly embedded in the encapsulant <NUM>. At least their second ends <NUM>, however, are not covered by the encapsulant <NUM> and protrude from the encapsulant <NUM> through the housing <NUM> to the outside of the housing <NUM>. The encapsulant <NUM> is configured to protect the components and electrical connections of the power semiconductor module <NUM>, in particular the components arranged inside the housing <NUM>, from certain environmental conditions and mechanical damage.

The housing <NUM> is mounted to the heat sink or base plate <NUM> by means of fastening elements <NUM>. The fastening elements <NUM> may comprise screws, pins with or without thread, studs with or without thread, or rivets, for example. (Threaded) bore holes <NUM> may be provided in the heat sink or base plate <NUM>. The fastening elements <NUM> are inserted into the bore holes <NUM>. The housing <NUM> comprises at least one protrusion <NUM> on its outside. The at least one protrusion <NUM> is attached to the sidewalls of the housing <NUM> at a lower end of the housing <NUM>. The lower end of the housing <NUM> is the end of the housing <NUM> which is attached to the heat sink or base plate <NUM>. The printed circuit board <NUM> is generally arranged close to an upper end of the housing <NUM> opposite the lower end and facing away from the heat sink or base plate <NUM>. Protrusions <NUM> may be attached to the housing <NUM> in any suitable way. For example, protrusions <NUM> may be glued to the housing <NUM>. It is also possible that the protrusions <NUM> are integrally formed with the housing <NUM>. First through holes <NUM> are provided in the at least one protrusion <NUM>. According to one example, one continuous protrusion <NUM> is provided along the entire circumference of the housing <NUM>, wherein a plurality of first through holes <NUM> is formed in the protrusion <NUM>. According to another example, two or more separate protrusions <NUM> are provided at different positions along the circumference of the housing <NUM>, wherein one or more first through holes <NUM> are formed in each of the protrusions <NUM>.

The fastening elements <NUM> may comprise an elongated body having a smaller diameter and a head having a diameter which is larger than the diameter of the elongated body. The diameter of the head is also larger than the diameter of the first through holes <NUM>. When a fastening element <NUM>, i.e., its elongated body, is inserted through one of the first through holes <NUM> and a respective bore hole <NUM> in the heat sink or base plate <NUM>, its head remains vertically above the protrusion <NUM> and presses the protrusion, and therefore the housing <NUM>, on the heat sink or base plate <NUM>. In this way, the housing <NUM> can be securely attached to the heat sink or base plate <NUM>. A housing <NUM> is usually mounted on a heat sink or base plate <NUM> by means of two or more fastening elements <NUM>. In the arrangement of <FIG>, the housing <NUM> does not contact the substrate <NUM>. It is, however, also possible that the housing <NUM> contacts the substrate <NUM> and presses the substrate <NUM> on the heat sink or base <NUM> when the housing <NUM> is mounted on the heat sink or base plate <NUM>. In this way, a satisfactory contact may be provided between the substrate <NUM> and the heat sink or base plate <NUM> in order to effectively conduct heat away from the substrate <NUM>.

The power semiconductor arrangement <NUM> is usually mounted on the heat sink or base plate <NUM> when it is already completely assembled. That is, the housing <NUM> is mounted on the heat sink or base plate <NUM> when the housing <NUM> is closed and the printed circuit board <NUM> is already securely attached to the terminal elements <NUM>. Therefore, second through holes <NUM> need to be provided in the printed circuit board <NUM> which allow to insert the fastening elements <NUM> through the first through holes <NUM> and into the bore holes <NUM> of the heat sink or base plate <NUM>. Even further, a tool for inserting and fixing the fastening elements <NUM> in the bore holes <NUM> needs to pass through the second bore holes <NUM>. A diameter d1 of the second through holes <NUM>, therefore, in the arrangement of <FIG> is required to be larger than the largest diameter d2 of the fastening elements <NUM>. The largest diameter d2 of the fastening elements <NUM> is usually the diameter of its head. The large second through holes <NUM>, however, consume lots of space of the printed circuit board <NUM> which cannot be used for arranging conducting tracks or any other elements thereon.

Now referring to <FIG>, a power semiconductor module arrangement <NUM> according to one example is schematically illustrated. The arrangement of <FIG> largely corresponds to the arrangement that has been described with respect to <FIG> above. The components arranged inside the housing <NUM> that have been described above are not specifically illustrated in <FIG>. The housing <NUM> in the example of <FIG> comprises additional holding devices <NUM>. Each of the holding devices <NUM> in this example is arranged between the printed circuit board <NUM> and a different one of the protrusions <NUM> in a vertical direction y. Each of the plurality of holding devices <NUM> is configured to clamp a different one of the fastening elements <NUM> such that the fastening elements <NUM> are secured in defined positions above the first through holes <NUM>. That is, each of the plurality of fastening elements <NUM> is aligned with a different one of the first through holes <NUM>. A fastening element <NUM> being aligned with a first through hole <NUM> means that a vertical axis A going through a center of the fastening element <NUM> corresponds to a vertical axis A going through the center of the respective first through hole <NUM>. The vertical axis A is perpendicular to a top surface of the heat sink or base plate <NUM>, wherein the top surface of the heat sink or base plate <NUM> is a surface on which the housing <NUM> is mounted. The fastening element <NUM> is further aligned with a respective one of the second through holes <NUM> in the printed circuit board <NUM>.

The fastening elements <NUM> can be inserted into the holding devices <NUM> before the printed circuit board <NUM> is mounted on the housing <NUM>. In some embodiments it is also possible to insert the fastening elements <NUM> into the holding devices <NUM> after the printed circuit board <NUM> has been mounted on the housing <NUM>. In the latter case, the fastening elements <NUM> are inserted into the holding devices <NUM> horizontally through the second through holes <NUM> of the printed circuit board <NUM> (instead of vertically, as has been described with respect to the conventional arrangement of <FIG> above). The power semiconductor module arrangement <NUM> comprising the housing <NUM> and the printed circuit board <NUM> can then be sold and shipped together with the fastening elements <NUM> that are securely held in place by the holding devices <NUM>. It is no longer necessary to insert the fastening devices <NUM> through the second through holes <NUM>. The second through holes <NUM> in the arrangement of <FIG>, therefore, may have a smaller diameter d3 as compared to the diameter d1 of the second through holes <NUM> of the arrangement of <FIG>. The second through holes <NUM> usually cannot be completely omitted, as it may still be necessary to reach the fastening elements <NUM> with an appropriate tool to insert and fasten them in the bore holes <NUM>. However, in the arrangement of <FIG>, a diameter d3 of the second through holes <NUM> is smaller than the largest diameter d2 of the fastening elements <NUM>. In this way, more of the area of the printed circuit board <NUM> is available for conducting tracks or any other components mounted on the printed circuit board <NUM>. According to one example, the diameter d3 of the second through holes <NUM> is between <NUM>% and <NUM>% smaller than the largest diameter d2 of the fastening elements <NUM>. For example, if the largest diameter d2 of the fastening element <NUM> is <NUM> (millimeter), the diameter d3 of the second through hole <NUM> may be between <NUM> and <NUM>, if a tool having a diameter of <NUM> is used to fix the fastening element <NUM> to the heat sink or base plate <NUM>. The diameter d3 of the second through holes <NUM> may solely depend on a size of the tool, for example, in particular it may be larger than the diameter of the tool that is used in order to prevent the tool from damaging the printed circuit board <NUM> when mounting the housing <NUM> on the heat sink or base plate <NUM>. In this way, up to <NUM>% of the surface area of the second through holes <NUM> of <FIG> can be provided as available surface area of the printed circuit board <NUM> in <FIG>.

In the example illustrated in <FIG>, the holding devices <NUM> are arranged vertically above the protrusions <NUM>. That is, the holding devices <NUM> are arranged between the protrusions <NUM> and the printed circuit board <NUM> along the sidewalls of the housing <NUM> in a vertical direction y. A holding device <NUM> of the arrangement of <FIG> is illustrated in greater detail in the detailed view of <FIG>.

Now referring to <FIG>, it is also possible to arrange the holding device <NUM> at least partly in the respective first through hole <NUM>. In the example illustrated in <FIG>, illustrated in greater detail in <FIG>, one part of the holding device <NUM> is arranged in the first through hole <NUM>, while another part of the holding device <NUM> is arranged above the protrusion <NUM>, between the protrusion <NUM> and the printed circuit board <NUM>.

The holding devices <NUM> can be implemented in many different ways. Several different examples of holding devices <NUM> will be described with respect to <FIG> below.

In order to securely hold the fastening device <NUM> in its desired position before it is inserted into the bore hole <NUM> in the heat sink or base plate <NUM>, the holding device <NUM> clamps the respective fastening device <NUM>. To achieve this clamping, the holding device <NUM> may contact the respective fastening element <NUM> in at least three different positions along a circumference of the fastening element <NUM>. The fastening element <NUM> may either be clamped at its head, where it has the larger diameter, or anywhere along its elongated body, where it has the smaller diameter. In the arrangement illustrated in <FIG>, for example, the fastening element <NUM> is clamped along its elongated body, as the holding device <NUM> is arranged partly inside the first through hole <NUM>. The head of the fastening element <NUM> is arranged above the protrusion <NUM> to be able to press the protrusion <NUM> against the heat sink or base plate <NUM> when the fastening element <NUM> is fully inserted in the bore hole <NUM>. In this arrangement, therefore, clamping the fastening element <NUM> at its head is generally not reasonable. In the arrangement of <FIG> and <FIG> on the other hand, the fastening element <NUM> may be clamped at its head. When inserting the fastening element <NUM> into the bore hole <NUM>, the fastening element <NUM> is pushed out of its initial position by means of an appropriate tool and the head of the fastening element <NUM> moves towards the protrusion <NUM> such that, in a final mounting position in which the housing <NUM> is securely mounted on the heat sink or base plate <NUM>, the head of the fastening element <NUM> contacts the protrusion <NUM> and presses it towards the heat sink or base plate <NUM>.

The holding device <NUM>, therefore, only exerts a certain minimum holding force on the fastening element <NUM>, in order to hold it in its desired position. When a tool is used to insert and securely fasten the fastening element <NUM> in the bore hole <NUM>, however, a force that is applied by the tool is greater than the holding force such that the fastening element <NUM> can be moved out of its initial position. The holding device <NUM> may contact the fastening element <NUM> in at least three different positions along its circumference. According to one example, the holding device <NUM> continuously contacts the fastening element <NUM> along its entire circumference.

According to one example, the holding device <NUM> comprises a threaded hole. The fastening element <NUM> in this example comprises a threaded elongated body that is inserted into the threaded hole of the holding device <NUM>. The tool may be a screwdriver or a hexagon key, for example, which is configured to screw the fastening element <NUM> into the bore hole <NUM>. At the same time, the fastening element <NUM> easily moves through the holding device <NUM> towards the heat sink or base plate <NUM>. In this example, the holding device <NUM> may be partly inserted into the first through hole <NUM> of the protrusion <NUM>, for example. It is also possible, for example, to arrange the holding device <NUM> between the protrusion <NUM> and the printed circuit board <NUM>, the holding device <NUM> directly adjoining the protrusion <NUM>.

According to another example, the holding device <NUM> comprises a sleeve <NUM> having a round cross-section. The sleeve <NUM> may extend continuously along its entire circumference. According to another example, however, the sleeve <NUM> comprises an interruption along its interference. That is, the sleeve <NUM> may extend along between <NUM>% and <NUM>% of its entire circumference, thereby forming a full circle, a semicircle or anything in between. Examples of sleeves <NUM> that comprise an interruption along their circumference are illustrated in <FIG>.

In the example illustrated in <FIG>, the holding device <NUM> comprises a bracket <NUM> which presses the fastening element <NUM> against the sleeve <NUM>. The bracket <NUM> may be arranged in the area along the circumference where the sleeve <NUM> is interrupted. The bracket <NUM> may be flexible. When the fastening element <NUM> is inserted into the holding device <NUM>, the bracket <NUM> is moved out of an initial position. The bracket <NUM> applies a horizontal force on the fastening element <NUM>, thereby pushing the fastening element <NUM> towards the sleeve <NUM> that is arranged opposite the bracket <NUM>, as the bracket <NUM> tries to return to its initial position. According to one example, the bracket <NUM> and the sleeve <NUM> are integrally formed with the protrusion <NUM>. <FIG> schematically illustrates a three-dimensional side-view, while <FIG> schematically illustrated a bottom view of the exemplary arrangement.

According to another example, and as is illustrated in <FIG>, a diameter d4 of the holding element <NUM> (the sleeve <NUM>) is the same as or even slightly less than a diameter d5 of the fastening element <NUM>. In the example illustrated in <FIG>, the diameter d4 of the sleeve <NUM> is slightly smaller than the diameter d5 of the head of the fastening element <NUM>. In this way, the fastening element <NUM> can be securely held in its desired position. However, by applying a force (e.g., a vertical force) that is larger than the holding force, the fastening element <NUM> may be moved out of its initial position and towards the heat sink or base plate <NUM>. According to one example, the holding element <NUM> (e.g., the sleeve <NUM> as illustrated in <FIG>) is not only configured to clamp the fastening element <NUM>, but may also be configured to extend a creepage distance between the fastening element <NUM> and any other elements of a power semiconductor module arrangement.

Now referring to <FIG>, it is also possible that the diameter of the sleeve <NUM> is larger than the diameter of the fastening element <NUM> (diameter of the head or diameter of the elongated body, depending on where the holding device <NUM> is arranged). At least three nubs <NUM> may be arranged along the circumference of the sleeve <NUM> between the sleeve <NUM> and the fastening element <NUM>. The nubs <NUM> reduce the diameter of the sleeve <NUM> in certain positions, thereby exerting a holding force on the fastening element <NUM> and holding it in its desired position. The nubs <NUM> may be formed of a comparably soft material that is compressible to a certain degree.

Several different examples of holding devices <NUM> have been explained above. However, the holding devices <NUM> may be implemented in any other suitable way.

Claim 1:
An arrangement (<NUM>) comprising:
a housing (<NUM>) and a printed circuit board (<NUM>) arranged vertically above the housing (<NUM>), wherein the housing (<NUM>) comprises
sidewalls;
at least one protrusion (<NUM>) attached to the sidewalls and arranged on the outside of the housing (<NUM>) at a lower end of the housing (<NUM>) distant from the printed circuit board (<NUM>), wherein a plurality of first through holes (<NUM>) are provided in the at least one protrusion (<NUM>);
a plurality of holding devices (<NUM>), wherein each holding device (<NUM>) is arranged inside one of the first through holes (<NUM>) and/or between the printed circuit board (<NUM>) and one of the first through holes (<NUM>); and
a plurality of fastening elements (<NUM>) configured to attach the housing (<NUM>) to a heat sink or base plate (<NUM>), wherein
each of the plurality of holding devices (<NUM>) is configured to clamp a different one of the fastening elements (<NUM>) such that the fastening elements (<NUM>) are secured in defined positions, and to align each of the fastening elements (<NUM>) with a different one of the first through holes (<NUM>),
the printed circuit board (<NUM>) comprises a plurality of second through holes (<NUM>), wherein each of the second through holes (<NUM>) is arranged vertically above and aligned with a different one of the plurality of fastening elements (<NUM>),
a diameter (d3) of each of the second through holes (<NUM>) is less than the largest diameter (d2) of the respective fastening element (<NUM>), and
when a defined force that is greater than a holding force of the respective holding device (<NUM>) is exerted on the fastening elements (<NUM>) by means of a tool passing through the respective second through holes (<NUM>), the fastening elements (<NUM>) are configured to move vertically through the respective first through holes (<NUM>) in a direction away from the printed circuit board (<NUM>).