Semi-finished product, method, and electronic device

Abstract

In one embodiment, the semi-finished product (11) is configured for an electronic device (1) intended to be loaded with a maximum current of at least 10 A, and includes an electronic component (3) and a plurality of power terminals (4) for externally electrically contacting the electronic device (1), the power terminals (4) being electrically connected to the electronic component (3) and extending in a direction away from the electronic component (3), the semi-finished product (11) further including a slide rail (5) at an end (41) of at least one assigned power terminal (4) away from the electronic component (3), the slide rail (5) being integrated into a metal first lead frame (45) together with at least one of the power terminals (4), and the semi-finished product (11) has a weight of at least 0.1 kg.

Description

[Technical field]

[0001] A semi-finished product for an electronic device is provided. Also provided is a method for using the semi-finished product. Also provided is an electronic device made from the semi-finished product. [Background technology]

[0002] Document CN 201 369 329 Y discloses a high-performance heat and moisture resistant lead frame that improves resistance to mechanical shock and thermal fatigue, thus extending the service life of the finished product.

[0003] Document CN 201 853 698 U discloses a short pin three-terminal lead frame.

[0004] Document JP 2016-207 974 A provides a lead frame having a plurality of leads, including small signal leads and power signal leads, which can suppress warping of the substrate caused by the difference in linear expansion coefficient between the substrate and the lead frame.

[0005] Document US 2016 / 0056095 A1 describes a leadframe strip with sawing enhancement features.

[0006] Document US 2019 / 0229044 A1 describes a leadframe that is formed with exposed lead tips. Summary of the Invention [Problem to be solved by the invention]

[0007] The problem to be solved is to provide a semi-finished product for an electronic device, the power terminals of which can be handled efficiently without being damaged. [Means for solving the problem]

[0008] This object is achieved in particular by the semi-finished product, the method and the electronic device as defined in the independent patent claims. Preferred further developments form the subject matter of the dependent claims.

[0009] For example, the semi-finished product has a slide rail that is subsequently removed. The slide rail is configured to be a support surface for the semi-finished product during at least one of storage (e.g. intermediate storage), processing, cleaning, inspection, testing, handling, and movement. Thus, only the slide rail and not the power terminals are at risk of being scratched during storage, processing, cleaning, inspection, testing, handling, and / or movement of the semi-finished product. This is true, for example, because the power terminals are made of a soft metal such as copper and the semi-finished product has a relatively large weight.

[0010] In at least one embodiment, the semi-finished product is for electronic equipment; - Optionally, a substrate and - For example, one or more electronic components; - a plurality of power terminals for externally electrically contacting the electronic device, the power terminals being electrically connected to the electronic components and extending in a direction away from the at least one electronic component; and - one or more slide rails at at least one end of the power terminals remote from the electronic component or substrate, at least one slide rail being integrated with one, some or all of the power terminals in a metallic first lead frame, at least one slide rail being capable of shorting the respective power terminals. For example, the semi-finished and finished electrical device has a weight of at least 0.1 kg and / or the electronic device is configured to be loaded with a maximum current of at least 10 A.

[0011] In at least one embodiment, the semi-finished product is for electronic equipment; - Optionally, a substrate and - For example, one or more electronic components; - a plurality of power terminals for externally electrically contacting the electronic device, the power terminals being electrically connected to the electronic components and extending in a direction away from the at least one electronic component; and - one or more slide rails at at least one end of the power terminals remote from the electronic component or board, at least one slide rail being integrated with one, some or all of the power terminals in a metallic first lead frame, at least one slide rail being capable of short-circuiting the respective power terminals. For example, the semi-finished and finished electrical device has a weight of at least 0.1 kg and / or the electronic device is configured for loading with a maximum current of at least 10 A. A nose piece is in each case located between one of the ends of the respective power terminals and the associated slide rail and is integrated in the first lead frame. The length of the nose piece between each end of the assigned power terminal and the slide rail is at most 25% of the lateral width of the slide rail.

[0012] The at least one electronic component is, for example, a semiconductor component. For example, the component is a high-power component such as a thyristor or a transistor. Various types of electronic components may be present in the semi-finished product, such as high-power components combined with an integrated circuit to provide a control function.

[0013] The term "power terminal" means that each terminal is configured to handle a maximum current of at least 10 A, or at least 50 A, or at least 100 A, or at least 500 A. The power terminal, and therefore the electrical device, is therefore designed to be loaded with high currents. The term "high power component" above therefore refers to such currents being delivered to the completed electrical device.

[0014] If the semi-finished product includes the substrate or substrates, then at least one electronic component is mounted, for example, on at least one of the substrates. Otherwise, at least one electronic component is mounted on the first lead frame itself or on another lead frame. If there are multiple substrates, then these substrates are mounted on a common base plate, for example a heat sink.

[0015] For example, if there is at least one substrate, the power terminals are rigidly attached to the substrate such that the first lead frame does not significantly move or bend relative to the substrate in the intended application. That is, the substrate can then be considered as a carrier for the at least one electronic component. Therefore, the first lead frame can be handled together with the substrate as a single rigid unit. For example, if the workpiece is held only by at least one slide rail and, optionally, at least one edge rail, the weight of the workpiece does not significantly change the shape of the workpiece.

[0016] According to at least one embodiment, the semi-finished product further comprises a nose piece, which is in each case located between one of the ends of the respective power terminal and the slide rail. For example, the nose piece is integrated into the first lead frame. For example, the cross-sectional area of ​​each of the nose pieces is at most 90% or at most 50% or at most 25% of the cross-sectional area of ​​the assigned power terminal. The cross-sectional area of ​​the nose piece is thus smaller than the cross-sectional area of ​​the assigned power terminal.

[0017] Alternatively or additionally, the nose piece may be an area between the respective end and the slide rail that includes a target break line, etc. The target break line may be achieved, for example, by a localized material weakening and / or by a thinner area of ​​the respective lead frame.

[0018] Such a nose piece allows easy removal of the at least one slide rail from the power terminal. The cross-sectional area refers, for example, to a cross section in a direction perpendicular to the main surface of the substrate and / or in a direction parallel to the direction of the main extent of the slide rail. The term "direction of the main extent" refers, for example, to the sliding direction.

[0019] There can be only one nose piece per power terminal, or there are two or more nose pieces per power terminal for all or some of the power terminals. Having two or more nose pieces per power terminal allows for a mechanically stable semi-finished product, for example, considering large power terminals.

[0020] According to at least one embodiment, the substrate comprises a non-metallic substrate. The substrate may, for example, be made of a ceramic or semiconductor material. For example, there is at least one coating on the substrate, for example a conductive metal coating. For example, the substrate may include one metal coating on each major surface. Such a substrate allows for efficient mounting and electrical contact of electronic components.

[0021] According to at least one embodiment, the thickness of the first lead frame is at least 0.2 mm and at most 5 mm, or at least 0.5 mm and at most 5 mm. For example, the thickness is 0.8 mm to 3 mm, such as 1.0 mm to 3 mm, so that the power terminals can supply high current to the device.

[0022] According to at least one embodiment, the length of the nose piece between each end and the assigned power terminal is at most 50%, 25% or 15% of the lateral width of the slide rail, thereby ensuring high mechanical strength of the first lead frame.

[0023] According to at least one embodiment, the width of the slide rail is at least 0.5 cm, or at least 1 cm, or at least 2 cm, or at least 3 cm, or at least 5 cm, in a direction perpendicular to the main extent of the assigned power terminal, for example in the direction in which the respective power terminal extends away from the substrate. Alternatively or additionally, the extent, i.e. the lateral width, of the slide rail is at least 1 mm, or at least 2 mm, or at least 3 mm, or at least 5 mm, or at least 7 mm, in a direction parallel to the main extent of the assigned power terminal. The slide rail can therefore be relatively long and provide a stable support surface for the workpiece, for example to avoid rotation and to ensure reliable guidance.

[0024] According to at least one embodiment, the width at the ends of the power terminals is at least 1 mm, or at least 3 mm, or at least 6 mm, or at least 10 mm, in each case perpendicular to the main extent of the respective power terminal. Alternatively or additionally, this width is at most 8 cm or at most 3 cm. This allows for highly conductive and mechanically stable power terminals.

[0025] According to at least one embodiment, the slide rail and the assigned power terminal have the same thickness and / or are made of the same material. The same may be true for the nose piece. Therefore, the power terminal and the slide rail and the optional nose piece can easily be manufactured from the same metal sheet.

[0026] According to at least one embodiment, the semi-finished product further includes a second lead frame. The second lead frame may, for example, be thinner than the first lead frame and include an auxiliary terminal. If there is at least one substrate, the auxiliary terminal may be attached to the substrate and, for example, extend away from the substrate. Thus, an additional terminal may be efficiently attached to the electronic device.

[0027] According to at least one embodiment, the second lead frame includes an edge rail. The edge rail or rails have the same function as the at least one slide rail, i.e., the at least one edge rail is configured as a support surface during storage, processing, cleaning, inspection, testing, handling, and / or movement of the semi-finished product, and is subsequently removed. The at least one edge rail can prevent damage, such as scratches, to the auxiliary terminals.

[0028] According to at least one embodiment, the edge rail is located along an edge of the second lead frame away from the substrate, and thus, in a top view, the edge rail can extend along an edge of the second lead frame. There can also be a nose piece, similar to the nose described above, as an optional feature of the first lead frame between the edge rail and the auxiliary terminal.

[0029] According to at least one embodiment, at least some of the auxiliary terminals are shorted by edge rails, similar to the slide rails in the power terminals, thus ensuring mechanical stability.

[0030] According to at least one embodiment, in a top view towards the main surface of the substrate, the edge rail is located along a different side of the substrate than the at least one slide rail, e.g., along an opposite side. For example, the main surface is the side of the substrate on which the at least one electronic component is located. Thus, the edge rail and slide rail together can form a stable support surface for the semi-finished product.

[0031] According to at least one embodiment, the second lead frame is made of a material having a higher hardness than the material from which the first lead frame is made. For example, the second lead frame has a hardness of at least 130HV, or at least 170HV, and / or up to 220HV. HV stands for Vickers hardness. Hardness refers to the conditions of the intended use of the electronic device, e.g., with respect to temperature. For example, the second lead frame is made of a copper alloy having a specified hardness.

[0032] According to at least one embodiment, the first lead frame is made of a material having a hardness of at most 90HV or at most 110HV and / or at least 60HV, for example, the first lead frame is made of copper or a copper alloy having a specified hardness.

[0033] According to at least one embodiment, the semi-finished product further comprises a molding. The molding can be, for example, made of a thermosetting polymer material or an epoxy resin material. For example, the substrate and the electronic components are partially or completely embedded in the molding. Thus, protection of the latter components can be provided by the molding.

[0034] According to at least one embodiment, the power terminals are only partially embedded in the molding and therefore protrude beyond the molding. This is true, for example, in a top view towards an electronic component or a substrate, if present. The term "top view" refers to the respective view without necessarily requiring that the respective components are actually visible, for example, if an opaque molding is present.

[0035] According to at least one embodiment, the at least one slide rail is located outside the molding, e.g., there is no contact between the molding and the slide rail, so that the slide rail can be easily removed from the power terminal.

[0036] According to at least one embodiment, in a top view towards the main surface of the substrate, the sidewall length of the molding is in each case at least 2 cm, or at least 4 cm, or at least 5 cm, or at least 6 cm, or at least 8 cm, and / or up to 0.2 m. The electronic device is therefore relatively large.

[0037] According to at least one embodiment, the weight of the semi-finished product and / or the electronic device is at least 0.1 kg, or at least 0.2 kg, or at least 0.3 kg and / or at most 2 kg, so that without the slide rails the risk of scratches on the power terminals increases significantly.

[0038] According to at least one embodiment, for example when viewed along the direction of the main extent of the slide rail, the molded body projects or ends flush with the slide rail. A space-saving arrangement is therefore possible, since the lateral dimension of the semi-finished product along the direction of the main extent of the slide rail can be determined by the molded body instead of the slide rail. Alternatively, the slide rail may be longer than the molded body and thus project.

[0039] According to at least one embodiment, the first lead frame is curved. For example, the ends of the slide rails and power terminals may be farther from a plane defined by the bottom side of the base plate or the bottom side of the substrate than the remainder of the first lead frame.

[0040] According to at least one embodiment, the first lead frame is planar, e.g. oriented parallel to the substrate. "Planar" means, for example, that the first lead frame is a structured metal plate that is not curved and is therefore planar and flat. In the present application, the terms "parallel" and "perpendicular" apply in each case with a tolerance of, for example, up to 15° or up to 10° or up to 5°, taking into account manufacturing tolerances.

[0041] According to at least one embodiment, the semi-finished product includes only one substrate. In this case, the semi-finished product is not a leadframe assembly, but the substrate and possibly the molding are already present in an individualized form. However, if a base plate is present, there may be more than one substrate mounted on the base plate, in which case the semi-finished product includes, for example, only one base plate with all substrates mounted thereon.

[0042] According to at least one embodiment, the electronic component is thermally connected to a base plate, which may have a protruding molding to allow for efficient cooling. For example, the electronic component may be indirectly connected to the base plate, such that an optional substrate or a respective lead frame may be located between the base plate and the electronic component, or the electronic component may alternatively be directly mounted to the base plate.

[0043] The semi-finished product includes multiple slide rails. For example, in top view, the slide rails run along different edges of the substrate or molding, e.g., along both sides, although there can also be more than one slide rail on the same substrate edge or molding edge. When there are multiple slide rails, it is possible that all slide rails belong to the same first lead frame, or that there are more than one first lead frame, each containing one or more of the slide rails. The same applies to the edge rails of the optional second lead frame.

[0044] Further provided is a method of using the semi-finished product, the method using one or more semi-finished products as shown in relation to at least one of the above-mentioned embodiments, and therefore features of the semi-finished products are also disclosed in the method and vice versa.

[0045] In at least one embodiment, the method includes temporarily storing the semi-finished products in a slotted magazine or temporarily processing the semi-finished products in the slotted magazine. For example, the slotted magazine includes guide rails. At least one slot of the slotted magazine, and thus at least one pair of guide rails, is configured to carry one or more semi-finished products.

[0046] According to at least one embodiment, the at least one slide rail slides on at least one of the guide rails during at least one of the introduction of the semi-finished product into the slotted magazine, the removal of the semi-finished product from the slotted magazine, and the processing of the semi-finished product in the slotted magazine. That is, the slide rail moves while being supported by the guide rail. By having the at least one slide rail, scratches on the power terminals are prevented.

[0047] According to at least one embodiment, the method further includes removing at least one slide rail. However, the ends of the power terminals remain intact or essentially intact upon removal, and the power terminals are, for example, shorted out by the removal. In other words, by removing the at least one slide rail, the power terminals are separated from each other and may become individual parts of the previously continuous first lead frame. The same applies to the optional second lead frame. The removal may be, for example, by cutting, breaking, filing, and / or milling.

[0048] Removal of the slide rail creates a removal point on the end of the terminal, which can be a stub that protrudes from the end or a recess into the end.

[0049] Further provided is an electronic device, which is made from a semi-finished product as shown in relation to at least one of the above-mentioned embodiments, such that features of the semi-finished product are also disclosed for the electronic device and vice versa.

[0050] In at least one embodiment, the electronic device comprises: - Optionally, a substrate and - at least one electronic component; - a plurality of metal power terminals for externally electrically contacting the electronic device, the power terminals being electrically connected to the electronic component and extending away from the electronic component; and - For example, a removal point at the end of the power terminal and - for example, a molding, the optional substrate and electronic components being partially or completely embedded in the molding, the power terminals being, by way of example, only partially embedded in the molding and protruding beyond the molding, The weight of the electrical device is at least 0.1 kg and / or the electronic device is configured to be loaded with a maximum current of at least 10A.

[0051] According to at least one embodiment, the end face of the removal point is a bare metal surface, for example obtained by removing the slide rail via the nose piece or via the power terminal. The remaining part of the power terminal that is not embedded in the molding can be provided with a coating. The bare metal end face consists, for example, of the core material of the power terminal, i.e., for example, of copper or a relatively soft copper alloy.

[0052] According to at least one embodiment, the removal points are stubs or recesses. The average length of the stubs or the average depth of the recesses is at most the thickness of the power terminal or at most 50% or at most 20% of said thickness. Alternatively or additionally, said length is at most 0.5 mm or at most 0.2 mm. Having such a small length or depth of the stubs or recesses can ensure that the removal points do not interfere with the function of the device. The average length or depth is the sum of all lengths or depths divided by the number of stubs or recesses, respectively.

[0053] The electric device may be, for example, a power module in an electric vehicle for converting direct current from a battery to alternating current for an electric motor, as an example in a hybrid or plug-in electric vehicle.

[0054] The semi-manufactured product, method and electronic device described herein will be described in more detail below by way of exemplary embodiments with reference to the drawings. Elements that are the same in the individual figures are indicated by the same reference numerals. However, the relationship between the elements is not shown to scale, and rather the individual elements may be shown exaggeratedly large to aid in understanding. [Brief description of the drawings]

[0055] [Figure 1] 1 is a schematic top view of an exemplary embodiment of a workpiece described herein. FIG. [Diagram 2] FIG. 2 is a schematic side view of the semi-finished product of FIG. 1. [Diagram 3] 1 is a schematic perspective view of an exemplary embodiment of a workpiece described herein; [Figure 4] 1 is a schematic top view of an exemplary embodiment of a workpiece described herein. FIG. [Diagram 5] 1 is a schematic perspective view of a power terminal and slide rail of an exemplary embodiment of a semi-finished product described herein; FIG. [Figure 6] 1 is a schematic perspective view of a power terminal and slide rail of an exemplary embodiment of a semi-finished product described herein; FIG. [Figure 7] 1 is a schematic perspective view of an exemplary embodiment of a workpiece described herein within a slotted magazine; [Figure 8] FIG. 2 is a schematic block diagram of an exemplary embodiment of a method of using a workpiece as described herein. [Figure 9] 1 is a schematic perspective view of an exemplary embodiment of an electronic device described herein. [Figure 10] 1 is a schematic perspective view of an exemplary embodiment of an electronic device described herein. [Figure 11]1 is a schematic top view of an exemplary embodiment of a workpiece described herein. FIG. [Figure 12] 1 is a schematic top view of an exemplary embodiment of a workpiece described herein. FIG. [Figure 13] 1 is a schematic cross-sectional view of an exemplary embodiment of an electronic device described herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0056] 1 and 2 show an exemplary embodiment of a semi-finished product 11 for an electronic device 1. In the embodiment shown in FIG. The semi-finished product 11 comprises a substrate 2. The substrate 2 is, for example, a ceramic substrate. It therefore comprises a non-metallic substrate 21, which may be made of a ceramic such as aluminium oxide. The substrate 2 comprises on its main surface 20 a metal coating 22, structured for example to form conductor tracks and electrical contact surfaces. The substrate 2 is, for example, rigid so as not to bend in the intended use of the semi-finished product 11. For example, the substrate 2 is a direct bond copper substrate (abbreviated DBC substrate), and the metal coating 22 is a metallization applied to the substrate 21.

[0057] For example, there is another metal coating 23 on the bottom side of the substrate 2. Optionally, the metal coatings 22, 23 may be electrically connected (not shown), for example by vias. Furthermore, there may be more than one metal coating 22, 23 per main surface of the substrate 2, and the stacked metal coatings 22, 23 may be separated by an additional insulating layer (not shown).

[0058] Optionally, there is a base plate 29 on the metal coating 23. The base plate 29 is for example a metal heat sink, but can also be another thermally conductive material, such as ceramic. The thickness of the base plate 29 exceeds the thickness of the substrate 2, for example, other than that shown in FIG. 2. The base plate 29 may overhang the substrate 29, but may also terminate flush with the substrate 2, or the substrate 2 overhangs beyond the base plate 29, as shown in FIG. 2. For simplicity of drawing, the base plate 29 is only shown in FIG. 2 and not in FIG. 1. Such a base plate 29 may also be present in all other exemplary embodiments.

[0059] On the main side 20 of the substrate 2, for example, there is present an electronic component 3, which is by way of example a semiconductor chip, although an electrical component 3 may alternatively be mounted later. There may be a number of electronic components 3 and / or much more complex patterns of conductor tracks, as the representations in Figures 1 and 2 are merely simplified. It is possible that at least one electronic component 3 is at least partially located on the metal coating 22. Furthermore, connection means such as bond wires 31 for contacting the at least one electronic component 3 may be present.

[0060] In the following, the substrate 2 and the circuits thereon will not be described in detail, however, the above-mentioned aspects of the substrate 2 and the electrical components 3 also apply, for example, to all other exemplary embodiments.

[0061] Semi-finished product 11 also includes a first lead frame 45. For example, first lead frame 45 is made from a relatively soft material, such as copper or a copper alloy with low hardness. First lead frame 45 may be, for example, a single piece of a single material. Alternatively, first lead frame 45 may be a composite of two or more materials. The same applies to all other exemplary embodiments.

[0062] The first lead frame 45 is constituted by the power terminal 4 and the slide rail 5. Optionally, there is a nose piece 6 between the power terminal 4 and the slide rail 5. The nose piece 6 is thinner, i.e. has a smaller width, than the power terminal 4. The nose piece 6 causes the end 41 of the power terminal 4 to project along the direction M of the main extent of the power terminal 4.

[0063] According to Fig. 1 and Fig. 2, there are two power terminals 4. However, there may be a different number of power terminals 4, for example up to 10 power terminals 4 or up to 6 power terminals 4. Furthermore, there may be more than one nose piece 6 per power terminal 4. For example, all power terminals 4 of the first lead frame 45 are connected to the same slide rail 5. The slide rail 5 is oriented, for example, perpendicular to the direction M, and the slide rail 5 may protrude beyond the substrate 2 in top view or may terminate flush with the substrate 2, differently from what is shown in Fig. 1. The same applies to all other exemplary embodiments.

[0064] The first lead frame 45 is for example curved, i.e. the ends of the slide rail 5 and the power terminals 4 are further from the upper metal coating 22 than the parts of the power terminals 4 adjacent to the electronic component 3. Alternatively, the first lead frame 45 may be flat without being curved out of the plane of the drawing of Fig. 1. The same applies to all other exemplary embodiments.

[0065] Additionally, first lead frame 45 is rigidly connected to substrate 2. That is, first lead frame 45 does not move or bend significantly relative to substrate 2 in the intended use of workpiece 11. For example, first lead frame 45 is connected to substrate 2 by friction welding, laser welding, sintering, or soldering.

[0066] The thickness t1 of the first lead frame 45 is, for example, greater than 1 mm, for example 1.2 mm. Thus, the first lead frame 45 is relatively rigid. The length L of the nose piece 6 is relatively small to ensure a rigid first lead frame 45. The length L is, for example, at most twice the thickness t1, or at most 1.5 times the thickness t1. For example, the length L is equal to the thickness t1, i.e. 1.2 mm in this example. The width of the nose piece 6 is, for example, at least 0.5 mm and / or at most 5 mm. The lateral width b of the slide rail 5 is, for example, at least 3 mm or 5 mm, so that a large support surface is provided by the slide rail 5. Alternatively or additionally, the lateral width b may be at most 10 mm. Furthermore, for example, the slide rail 5 has a large width w along the substrate 2 of at least 5 cm and / or at most 10 cm. The same applies to all other exemplary embodiments.

[0067] Optionally, the semi-finished product 11 may include a second lead frame 78. The second lead frame 78 includes, for example, auxiliary terminals 7 configured to provide control signals to the electrical component 3. Furthermore, there are edge rails 8 connecting the auxiliary terminals 7. Since the current supplied through the auxiliary terminals 7 is smaller compared to the power terminals 4, the auxiliary terminals 7 are thinner and the second lead frame 78 has a smaller thickness t2, for example, at least 0.1 mm and / or at most 0.25 mm or at most 0.8 mm. For example, the thickness t2 is 0.6 mm. Unlike the one shown in FIG. 1, the second lead frame 78 may also include a nose piece similar to the first lead frame 45. The second lead frame 78 may be flat or may also include a bend. For example, the second lead frame 78 is made of a relatively hard material.

[0068] The second lead frame 78 may be replaced by another first lead frame, so that there may be two first lead frames 45. It is also possible that there are two second lead frames 78. Furthermore, the second lead frame 78 may be supplemented by another first lead frame 45, so that there may be an overlapping or alternating arrangement, or the lead frames 45, 78 are arranged next to each other in a top view. Furthermore, in a top view, there may be lead frames, such as the first lead frame 45, for example, on not only two sides of the substrate 2, but also on three or four sides. The same applies to all other exemplary embodiments.

[0069] The semi-finished product 11 of Fig. 3 further comprises a moulded body 9. The side wall length B of the moulded body 9 may be large, being at least 4 cm and / or at most 20 cm. The moulded body 9 may protrude a slide rail 5. The thickness of the moulded body 9 is, for example, at least 3 mm or 5 mm and / or at most 2 cm or 5 cm.

[0070] Optionally, there are two first lead frames 45 on either side of the molding 9. However, there can also be four first lead frames 45 on all four sides of the molding 9. As in Figures 1 and 2, an optional second lead frame 78 including an edge rail 8 may also be present. If a base plate 29 is present as shown in Figure 2, the base plate 29 protrudes the molding 9 in a direction away from the metal coating 23, for example.

[0071] In other respects, the same applies to FIG. 3 as to FIGS. 1 and 2. FIG. 4 provides a diagram of an exemplary embodiment of the semi-finished product 11. The first lead frame 45 and the optional second lead frame 78 have a more complicated shape than those in FIGS. 1-3. On the side of the second lead frame 78, there is an additional terminal 4 that may be part of the additional first lead frame 49 without a slide rail. That is, the thicker additional first lead frame 49 and the thinner second lead frame 78 are mounted alternately. Because of this alternating arrangement, it is only necessary for the second lead frame 78 to include an edge rail 8, and there is no need for the additional first lead frame 49 to have an additional slide rail.

[0072] There may be additional noses between adjacent power terminals 4 of the first lead frame 45, and the power terminals 4 may have different shapes. This is also true for the second lead frame 78, as in all other exemplary embodiments. Furthermore, the molding 9 may have a more complex shape, but is still cubic in shape. Furthermore, the auxiliary terminals 7 may optionally be provided with pins 71 or the ends of the auxiliary terminals 7 may be shaped like pins 71.

[0073] The terminal structure in Figure 4 refers to the situation before the trim and form process where the dambar and surrounding lead frame components are removed. During the trim and form process, the power terminals 4 are de-shorted.

[0074] As with all other exemplary embodiments, the width v of the power terminals 4 is, for example, at least 0.5 cm, at least 1 cm, and / or at most 5 cm. The lateral width b of the edge rail 8 and the lateral width b of the slide rail 5 may be the same, but for the second lead frame 78, the lateral width b may refer to the minimum lateral width. The entire edge rail 8 may have a fairly complex shape, such that the auxiliary terminals 7 are produced by punching the second lead frame 45 and are clearly visible immediately after such punching process.

[0075] Further options for the nose piece 6 are shown in Figures 5 and 6. According to Figure 1, the nose piece 6 has the same thickness as the power terminal 4. In Figure 5, the nose piece 6 has the same width as the power terminal 6, but is thinner than the power terminal 6, whereas the power terminal 6 and the slide rail 5 can still have the same thickness. Figure 6 shows a combination of the nose pieces 6 shown in Figures 1 and 5, i.e. the nose piece is thinner and narrower than the power terminal 4 and the slide rail 5.

[0076] Thus, the nosepiece 6 of Figures 1, 5 and 6 can be used in all exemplary embodiments.

[0077] 7 shows a slotted magazine 110 for storage and / or processing with guide rails 111. On the guide rails 111 in the slotted magazine 110 there are semi-finished products 11. In connection with FIG. 7 the effect of the slide rails 5 is explained in more detail below.

[0078] In the power semiconductor market, there is a trend towards large molded power packages with package bodies with side lengths of up to 80 mm, i.e. the molded body and the lead frame 45 made of thick copper sheets. An example of the use of corresponding large power packages is in the automotive sector.

[0079] There are many challenges not only in the realization of such a design of the power package, but also in the manufacturing process. Here, not only all the process steps during production themselves must be taken into account, but also the handling and storage of these modules between the individual production steps and the introduction of the modules into the production machine. The module design must therefore take into account the problems of handling, processing and storage.

[0080] Molded leadframe-based packages are used, for example, in the IC market, but also in power electronics for relatively small power packages. These packages are relatively small, with body sizes of up to about 40 mm in side length and a few millimeters in thickness. A package weight of a few grams is therefore not significant and is of minor concern. In addition, most of the leadframes used for the corresponding products are made from relatively hard copper alloys, such as C7025 or C19400.

[0081] It is clear that the weight of the novel large molded power package of the semi-finished product 11 and electronic device 1 described herein, having a molded body size of about 80 mm side length and about 10 mm thickness and having a lead frame at least partially including a thick copper plate, would otherwise be much larger. The weight of such a module can be about 300 g or even more, without considering the optional base plate 29. In contrast to the small molded package, at least most of the thick power terminals 4 are made from relatively soft pure copper or a soft copper alloy with a small content of other materials that provide optimal electrical conductivity.

[0082] In the manufacture of molded packages, the leadframe strip with chips and moldings is typically stored or processed in a slotted magazine 110, which is the standard method of storage, processing and handling, where the leadframe strip is inserted into the slots with the periphery of the strip resting on a positioning bar. Generally, it is also possible to store large molded power packages in a slotted magazine, as shown in FIG. 7.

[0083] However, the positioning bars or guide rails 111 in the slot magazine 110 provide exposed metal surfaces. Therefore, metal-to-metal mechanical contact occurs during loading and unloading. This is not critical for IC packages having only a small weight combined with a relatively hard copper alloy, for example if only the periphery of the lead frame, which is later removed in the trim-and-form process, is used for positioning. Otherwise, for the large molded power packages described herein having a significant weight of several hundred grams, for example if the affected terminals are made from relatively soft copper or soft copper alloy, this metal-to-metal contact would provide a mechanical shock to the lead frame. For example, positioning is provided on one side by the periphery 8 of the second lead frame strip 78 on the side of the auxiliary terminal 7 and on the other side by the end of the thick wide power terminal.

[0084] This is less critical on the side of the auxiliary terminal 7 made from hard copper alloys where there is an area of ​​edge rail 8 that is later removed in the trim and form process. For example, on the side of the power terminal 4 made from soft pure copper or soft copper alloys that is exposed to mechanical contact, in the absence of slide rail 5, the movement of the power package during loading or unloading will cause scratches on the terminal due to mechanical shocks. These scratches can be a significant issue in terms of visual acceptance and, although at first glance it may only be a cosmetic issue, can ultimately jeopardize customer acceptance. In addition, corresponding scratches can cause problems with the terminal connection to the busbar in the customer application.

[0085] The semi-finished product 11 of the invention, and the resulting electronic device 1, are based on an approach to prevent the occurrence of scratches on the power terminals 4 by an improved lead frame layout when loading and unloading the module 11 into and from the slotted magazine 110. This is realized, for example, as shown in FIG. 4, by an additional slide area of ​​the first lead frame 45, which is attached to the front side, i.e. the end 41, of the power terminals 4. This slide area is realized by a slide rail 5, which suffers a mechanical metal-to-metal contact to a positioning bar 111 in the slotted magazine 110 instead of the power terminals 4. As the slide area is attached to the power terminals 4 by a small nose piece 6, the slide rail 5 can be easily removed by stamping during the trim and form process at the end of the manufacturing process. Therefore, scratches on the slide area are not critical. This also applies to the optional second lead frame.

[0086] Regarding the cost of the new lead frame design presented here, there is no significant increase in cost compared to the previous lead frame design. However, the first lead frame and possibly the second lead frame may require slightly more material, but the material that is later removed can be reused. The introduction of the slide rail 5 only reduces the waste on the supplier side during the stamping process.

[0087] Thus, the design feature of the present application can be highlighted as an additional side rail portion 5 of the first lead frame 45 of the power module 11 , which is attached to the front surface 41 of the terminal 5 with a nose piece 6 .

[0088] Thus, the difference between the first leadframe 45 used for large molded power packages and the first leadframe 45 used for small IC packages arises not only from the size of the package body 9, but also from the type of terminals 4. The package body 9 of the large molded power package has a large side length, so that the leadframe strip may have the width of only one power module 11, or the leadframe strip 5 may be associated with a power package design in which the power and auxiliary terminals 4, 7 are made from different copper alloys, so that it provides terminals 4 on only one side. In contrast, in the case of IC packages, the leadframe strip used for production may include several rows of small packages in which terminals made of the same material are positioned on two or all four sides of the package body.

[0089] The thickness of the first lead frame 45 for the power terminals 4 is significantly greater than that used for small molded packages. The thickness of the lead frame, and therefore the terminals, used for small molded packages, e.g. IC packages, is a maximum of 0.25 mm, whereas the thickness of the power terminals 4 of large molded power packages is 1 mm or more. In addition, the width of the terminals used for small molded packages is typically less than 1 mm, whereas the width of the power terminals 4 of large molded power packages can be greater than 10 mm.

[0090] For large molded power packages, the terminal structure may be realized by two different lead frame strips of different materials. Therefore, most of the thick power terminals 45 are made from soft pure copper or soft copper alloy to provide optimal electrical conductivity. The thin auxiliary terminals 7, which do not require high current capability but do require sufficient mechanical stability, are made from, for example, a harder copper alloy.

[0091] Due to the large width and thickness of the power terminal 4, for example, there is no connection between the slide rail 5 and the entire front side of the terminal 4. As a result, a small nose piece 6 is needed to facilitate the removal of the slide rail 5 forming the slide area by stamping during the trim and form process.

[0092] In Fig. 8 the use of the semi-finished product 11 is only diagrammatically shown. According to step S1, a semi-finished product 11 is provided with a substrate 2 and a first lead frame 45, which may be stored in a slot magazine 110 or may be handled by means of rails. Optionally, at least one electronic component 3 is already mounted on the substrate 2. Thus, in method step S1 the semi-finished product corresponds to a configuration similar to that shown in Figs. 1 and 2.

[0093] In method step S2, the molded body 9 is formed (compare for example FIG. 3). Then, in optional method step S3, the molded body 9 is hardened, i.e. a post-molding hardening takes place, which can take place with the semi-finished product 11 again accommodated in the slot magazine 110.

[0094] In method step S4, the semi-finished product 11 is stored again in the slotted magazine 110 and optionally tested or inspected. For the test or inspection, the semi-finished product 11 may be temporarily removed from the slotted magazine 110 and may be inserted again in the slotted magazine 110 for a geometrical test, for example by X-ray analysis.

[0095] Finally, in method step S5, the at least one slide rail 5 and optionally present edge rails 8 are removed in a trim and form process to obtain the finished electrical device 1 (see FIG. 9).

[0096] There may be additional method steps not shown in Figure 8, such as a cleaning step before the shaping step S3, or further processing steps. Thus, the method shown in Figure 8 can be supplemented by additional method steps, or some method steps may be omitted or replaced by other method steps.

[0097] 9 and 10, an example of a completed electrical appliance 1 is shown. Compared to the semi-finished product 11, the electrical appliance 1 no longer has the rails 5, 8. Thus, removal points 42 are present in the place of the previous rails 5, 8.

[0098] 9, a small stub may be left at the end 41 from the nose piece 6 or from the slide rail 5 at the removal point 42. The stub results from the removal of the nose piece 6, for example by punching. The stub thus includes, for example, a bare metal end surface 44 formed by the removal of the nose piece 6.

[0099] The remaining part of the power terminal 4 may be provided with a coating 43, for example to protect the power terminal 4 from corrosion and / or to improve electrical contact to the power terminal 4 when the equipment 1 is installed by a customer. This applies, for example, to the main faces of the power terminal 4, but the side faces including the ends 41 may be free of a coating, such as the end faces 44. The end faces 44 may have a higher average roughness than the other surfaces of the power terminal 4.

[0100] As shown in Fig. 10, the removal points 42 are not in the form of stubs, but rather small recesses into the end 41 of the power terminal 4. Furthermore, as in all other exemplary embodiments, there may be more than one removal point 42 per power terminal 4. Otherwise, the same applies to Fig. 10 as to Fig. 9, for example with respect to the at least one coating 43.

[0101] Various configuration options are shown in the exemplary embodiment of Figures 11 and 12. On the right side of Figure 11, there is a first lead frame 45a similar to Figure 1. There can be one or more first lead frames 45b (see the left side of Figure 11), each of the power terminals 4 having its own slide rail 5. For example, the width b of each slide rail 5 is greater than the width v of the associated power terminal 4.

[0102] 11, there are optionally additional first lead frames 49 without slide rails, i.e. the slide rails 5 of the first lead frames 45a, 45b may be sufficient to support and guide the workpiece 11. At least one of the first lead frames 45a, 45b, 49 may be replaced by a second lead frame with edge rails (not shown).

[0103] 11, the slide rail 5, or at least one of the slide rails 5, may have scratches 55 along the sliding direction R of the semi-finished product 11 due to the semi-finished product 11 sliding along the slide rail 5 during manufacturing. For example, the depth of the scratch 55 is at least 5 μm and / or at most 0.1 mm. Otherwise, the surface roughness Ra of the at least one first lead frame is, for example, at most 0.5 μm. The same may apply to all other embodiments.

[0104] According to Fig. 12, there is one common slide rail 5 extending along different sides of the molding 9. There can be a different number of power terminals 4 and different designs of nose pieces 6 along different sides of the molding. Alternatively, there may be four slide rails 5, each along one side of the molding 9. As in Fig. 11, at least one of the power terminals 4 may be replaced by an auxiliary terminal (not shown), as long as at least two of the power terminals 4 remain.

[0105] The various designs shown in Figures 11 and 12 may be used in all other exemplary embodiments either individually or in combination where appropriate.

[0106] In Fig. 13 another exemplary embodiment of the electric device 1 is shown. The electronic components 3, i.e. semiconductor chips, are mounted directly on the power terminals 4 and the electrical wiring may be realized by bond wires 31, i.e. no substrate is required. Auxiliary terminals may also be present (not shown). The same may apply to all other embodiments of the electric device 1 and semi-finished product 11, as the substrate 2 may be optional.

[0107] As a further possibility, a base plate 29 may be present, to which the power terminals 4, and optional auxiliary terminals, may be attached. In this case, the base plate 29 includes an electrically insulating layer near the terminals or consists of an electrically insulating material. As a further option (not shown), at least one of the electronic components 3 may be mounted directly on the base plate 29 without an intermediate substrate or terminals. The same applies to all other embodiments.

[0108] The invention described herein is not limited by the description provided with reference to the exemplary embodiments, but rather the invention encompasses any novel feature and any combination of features, including any combination of features specifically recited in the claims, even if that feature or combination itself is not explicitly recited in the claims or exemplary embodiments.

[0109] This patent application claims priority to European Patent Application No. 20194119.2, the disclosure of which is incorporated herein by reference. [Explanation of symbols]

[0110] List of References 1 Electronic equipment 11 Semi-finished products for electronic devices 2. Board 20 Main surface of the substrate 21 Non-metallic substrate of the substrate 22 Metal coating on the upper side (main surface) 23 Metal coating on the bottom side 29 Base Plate 3. Electronic Components 31 Bond wire 4 Power terminal 41 Power terminal end 42 Removal points at ends 43 Coating 44 Bare metal end surface at removal point 45 First lead frame 49 Additional 1st Lead Frame 5 Slide rail 55 Scratch 6 Nose piece 7 Auxiliary Terminal 71 pin 78 Second lead frame 8 Edge Rail 9 Molded body 110 Slot Magazine 111 Guide rail b Slide rail width B: Side wall length of molded body t1 Thickness of the first lead frame t2 Thickness of second lead frame v Power terminal width w Slide rail width M Direction of main range of power terminal R Slide direction S. Method steps

Claims

1. A semi-finished product (11) for an electronic device (1) configured to be loaded with a maximum current of at least 10 A, - an electronic component (3); a plurality of power terminals (4) for electrically contacting the electronic device (1) from the outside, the power terminals (4) being electrically connected to the electronic component (3) and extending in a direction away from the electronic component (3); the semi-finished product (11) further comprises - a slide rail (5) at an end (41) of at least one assigned power terminal (4), each end (41) being remote from the electronic component (3); said slide rail (5) is integrated with at least one of said power terminals (4) into a first metallic lead frame (45); - the weight of said semi-finished product (11) is at least 0.1 kg; the width (w) of said slide rail (5) is at least 1 cm in a direction perpendicular to the main extent (M) of at least one of said assigned power terminals (4); the extent (b) of the slide rail (5) is at least 1 mm in a direction parallel to the main extent (M) of the assigned power terminal (4); the width (v) of said power terminals (4) at said ends (41) is in each case at least 1 mm in said direction perpendicular to said main extent (M) of each said power terminal (4); The slide rail (5) has a slide area which slides on a guide rail (111) of the slotted magazine (110) so that the semi-finished product (11) is introduced into and removed from the slotted magazine (110).

2. Further comprising a nose piece (6), - said nose piece (6) is in each case located between one of the ends (41) of the respective power terminal (4) and the associated slide rail (5); A semi-finished product (11) according to claim 1, wherein said nose piece (6) is integral with said first lead frame (45).

3. 3. The semi-finished product (11) according to claim 2, wherein the length (L) of the nose piece (6) between the end (41) of each assigned power terminal (4) and the slide rail (5) is a maximum of 25% of the lateral width (b) of the slide rail (5).

4. Further comprising a substrate (2), said electronic component (3) is mounted on said substrate (2); A semi-finished product (11) according to any one of claims 1 to 3, in which the power terminals (4) are rigidly attached to the substrate (2) and extend away from the substrate (2).

5. 5. The semi-finished product (11) according to claim 4, wherein the slide rail (5) integrated in the first lead frame (45) shorts all the power terminals (4) of the first lead frame (45).

6. The semi-finished product (11) according to any one of the preceding claims, wherein the slide rail (5) and the assigned power terminal (4) have the same thickness and / or consist of the same material.

7. The semi-finished product (11) according to any one of the preceding claims, wherein the first lead frame (45) consists of copper or a copper alloy having a hardness of up to 110 HV.

8. Further comprising a second lead frame (78); - said second lead frame (78) is thinner than said first lead frame (45) and includes auxiliary terminals (7); The semi-finished product (11) according to any one of the preceding claims, wherein the second lead frame (78) comprises an edge rail (8).

9. Further comprising a substrate (2), - said edge rail (8) is located along the edge of said second lead frame (78) remote from said substrate (2); at least some of said auxiliary terminals (7) are short-circuited by said edge rail (8); the edge rail (8) is located along a different side of the base plate (2) than the slide rail (5); - a semi-finished product (11) according to claim 8, in which the second lead frame (78) consists of a copper alloy having a higher hardness than the material of the first lead frame (45).

10. Further comprising a molded body (9), said electronic component (3) is at least partially embedded in said molded body (9); the power terminal (4) is partly embedded in the molded body (9) and projects beyond the molded body (9) in a top view; The semi-finished product (11) according to any one of claims 1 to 9, wherein the slide rail (5) is located outside the profile (9).

11. Further comprising a base plate (29); 11. The semi-finished product (11) according to claim 10, wherein the electronic component (3) is thermally connected to the base plate (29), the base plate (29) protruding from the molded body (9).

12. 12. A semi-finished product (11) according to claim 10 or 11, wherein, when viewed along the direction of the main extent of the slide rail (5), the shaped body (9) protrudes from the slide rail (5) or terminates flush with the slide rail (5), and the slide rail (5) is spaced apart from the shaped body (9).

13. A method in which a semi-finished product (11) according to any one of claims 1 to 12 is used, comprising the steps of: - temporarily storing said semi-finished products (11) in a slotted magazine (110) or temporarily processing said semi-finished products (11) in said slotted magazine (110), said slotted magazine (110) including a guide rail (111), At least one of the slide rails (5) slides on at least one of the guide rails (111) during at least one of the introduction of the semi-finished product (11) into the slotted magazine (110) and the removal of the semi-finished product (11) from the slotted magazine (110).

14. - further comprising removing at least one said slide rail (5), The method of claim 13, wherein the end (41) remains intact.

15. An electronic device (1) configured to be loaded with a maximum current of at least 10 A, - an electronic component (3); a plurality of power terminals (4) for electrically contacting the electronic device (1) from the outside, the power terminals (4) being electrically connected to the electronic components (3), extending in a direction away from the electronic components (3) and configured to be connected to a slide rail (5); the electronic device (1) further comprises: a removal point (42) at the end (41) of said power terminal (4); a molding (9), said electronic component (3) is at least partially embedded in said molded body (9); - said power terminals (4) are partly embedded in said moulded body (9) and protrude beyond said moulded body (9); - the thickness of said power terminal (4) is at least 0.5 mm; the end face (44) of said removal point (42) is a bare metal surface; - said electronic device (1) weighs at least 0.1 kg; - the average length or depth of said removal point (42) is at most the thickness of said power terminal (4); The slide rail (5) has a slide area, and the slide area slides on a guide rail (111) of the slot magazine (110), thereby allowing the electronic device (1) to be introduced into and removed from the slot magazine (110).

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