Semiconductor component and method for manufacturing a semiconductor component

Abstract

A semiconductor device (1) comprises a package (5) with a mounting surface (6), a conductor frame (2) embedded in the package (5) with at least two electrical contact pads (7, 8), and at least one semiconductor chip (13) arranged in the package (5) and electrically connected to the contact pads (7, 8). The conductor frame (2) has a solder control structure (9) with a recess (11) accessible at the mounting surface (6) and at least one side wall (10) of the package (5) for receiving solder material. The contact pads (7, 8) and the solder control structure (9) are formed by separate and unconnected sections of the conductor frame (2).

Description

The present invention relates to a semiconductor device and a method for manufacturing a semiconductor device.Surface-mountable optoelectronic components with solder control structures for receiving a solder material are known from the prior art. The solder control structures enable, inter alia, a self-alignment of the optoelectronic components with respect to solder contact pads, for example with respect to solder contact pads of a printed circuit board (PCB for short).A disadvantage of previously known optoelectronic components with solder control structures is that stresses are caused in the component by mechanical loads. This can result in cracks and fractures in the housing of the component.It is an object of the present invention to provide an improved semiconductor component and to specify an improved method for producing a semiconductor component. This object is achieved by a semiconductor component and a method for producing a semiconductor component having the features of the respectively independent claims. Advantageous further developments are specified in dependent claims.A semiconductor component has a housing with a mounting surface, a lead frame embedded in the housing with at least two electrical contact pads, and at least one semiconductor chip arranged in the housing and electrically connected to the contact pads. The lead frame has a solder control structure with a recess accessible on the mounting surface and at least one side wall of the housing for receiving a solder material. The contact pads and the solder control structure are formed by separate and discontinuous portions of the leadframe.The semiconductor component can be formed, for example, as an optoelectronic component. In this case, it has at least one optoelectronic semiconductor chip. The optoelectronic semiconductor chip can be configured, for example, to emit electromagnetic radiation. In this case, the at least one optoelectronic semiconductor chip can be embodied as a light emitting diode (LED) or, for example, as a laser diode.The optoelectronic component can have a plurality of optoelectronic semiconductor chips, for example it can have three light emitting diodes and be configured for example as an RGB light emitting diode which is configured to emit light of the colors red, green and blue. In this case, the optoelectronic component can be formed as a pixel element of a display device. However, the optoelectronic component can also be formed, for example, as a LiDAR device (light detection and ranging, LiDAR). In this case, the at least one semiconductor chip is designed as a laser diode.The at least one optoelectronic semiconductor chip can alternatively also be configured to detect electromagnetic radiation, for example the optoelectronic semiconductor chip can be configured as a photodiode.However, the semiconductor component does not necessarily have to be formed as an optoelectronic component. It can also be formed as an electronic component with at least one electronic semiconductor chip. The electronic semiconductor chip may be formed as any integrated circuit (IC).In another embodiment, the semiconductor component can also be formed as a microelectromechanical component with a microelectromechanical semiconductor chip. A microelectromechanical semiconductor chip can be designed, for example, as a pressure sensor, as an acceleration sensor or as another sensor.The semiconductor component can be formed, for example, as a so-called quad flat no leads package (QFN package). A QFN component is distinguished in that electrical connections connected to the contact pads do not project beyond the housing of the semiconductor component, but are accessible or are exposed only on the side walls and / or the mounting surface of the housing and are not covered by a housing material. A QFN component offers the advantage that it is particularly compact and thus space-saving.The semiconductor component is formed as a surface mount device (SMD) by the solder control structure, i.e. the semiconductor component can be mounted on a printed circuit board (PCB), for example, wherein a solder material is used for fastening. For this purpose, the solder material is arranged, for example, on solder contact pads of the printed circuit board. The semiconductor component is then arranged on the solder contact pads provided with the solder material and the solder material is cured. In contrast to the solder contact pads of the printed circuit board, the electrical contact pads of the semiconductor component can also be referred to as chip contact pads. The two chip contact pads of the semiconductor component are formed by separate lead frame sections in order to be able to electrically contact the semiconductor chip.One concept underlying the semiconductor component is to separate the solder control structure from other lead frame components. For this reason, the solder control structure is formed as a component of the leadframe which is separate from the electrical contact pads. In other words, the solder control structure and the contact pads are not connected to each other. Advantageously, this can significantly reduce a bundling of mechanical stresses at the solder control structures. In previously known embodiments of surface-mountable semiconductor components, the electrical contact pads are firmly connected to the solder control structures in comparison therewith. In other words, the contact pads and the solder control structures in previously known semiconductor components are formed by common and contiguous sections of the leadframe.A mechanical separation of the solder control structure from the remaining parts of the lead frame may be advantageous in various respects. For example, the housing, which can be produced, for example, by injection molding, is mechanically more stable, since stresses are not bundled on the solder control structure. Cracks and fractures in the housing can thereby be advantageously avoided. Since the mechanical requirements for the housing material are lower, housing materials which are advantageous in other respects than the mechanical stability are also suitable for the selection.The solder control structure is floating by being separated from the contact pads and not electrically connected thereto and may be referred to as a floating ground (floating potential). This offers the advantage that a plurality of semiconductor components can be arranged particularly close to one another without having to fear short circuits. In addition, a lateral positioning of the solder control structure with respect to the mounting surface of the housing is more freely selectable than in the case of a solder control structure fixedly connected to a contact pad.In one embodiment, the lead frame has at least two solder control structures with recesses for receiving a solder material that are accessible on the mounting surface and at least one side wall of the housing. The contact pads and the solder control structures are formed by separate and discontinuous portions of the leadframe.Advantageously, the semiconductor component aligns itself automatically into a desired azimuthal orientation, for example when mounted on a printed circuit board. This orientation is essentially predefined by the solder contact pads of the printed circuit board. If the semiconductor component with the solder control structures is arranged azimuthally offset with respect to the solder contact pads, forces act on the semiconductor component, said forces being determined substantially by boundary surface energies at the boundary surfaces between the solder control structures and the solder material, between the solder material and the solder contact pads and between the solder material and a surrounding area of the semiconductor component. These interfacial forces cause effective torque to act on the housing, thereby aligning until an energy stable configuration is achieved. This is the case if the solder control structures of the semiconductor component are arranged directly above the solder contact pads of the printed circuit board.In one embodiment, the solder control structures are arranged on mutually opposite side walls of the housing and / or in the region of corners of the housing. Advantageously, the arrangement of the solder control structures on mutually opposite side walls of the housing and / or in the region of the housing corners brings about a particularly effective self-alignment of the semiconductor component during surface mounting.The mechanical separation of the at least one solder control structure from the remaining parts of the leadframe, i.e. from the electrical contact pads or chip contact pads, increases the risk that the solder control structure is torn out of the housing during the singulation of a leadframe assembly or a housing body assembly as part of the production of a plurality of semiconductor components. This can be counteracted advantageously by a mechanical anchoring. For this reason, in one embodiment, the solder control structure has at least one anchoring embedded in the housing.In one embodiment, the anchoring is beam-shaped and protrudes from the solder control structure in a direction parallel to the mounting surface. This advantageously ensures reliable anchoring. In another embodiment, the solder control structure has a connecting element connected to the anchoring. In this embodiment, the solder control structure is anchored in the housing in a particularly reliable manner.In one embodiment, at least one contact pad has a further solder control structure with a further recess, which is accessible at least on the mounting surface of the housing, for receiving a solder material. In contrast to the solder control structure, the further solder control structure is firmly connected to the contact pad or chip contact pad. The further solder control structure and the chip contact pad are thus formed by a common portion of the leadframe. The further recess of the further solder control structure can also be accessible on at least one side wall of the housing in addition to the mounting surface. The further solder control structure can be mechanically fixedly connected to the chip contact pad via a connecting web of the leadframe. Advantageously, this enables electrical contacting of the chip contact pad connected to the further solder control structure via a solder material arranged between the further solder control structure and a solder contact pad.In one embodiment, the housing has a cavity. The contact pads are not covered by a housing material at least in sections and are exposed at a base of the cavity arranged parallel to the mounting surface. The semiconductor chip is arranged at the base of the cavity. Advantageously, the cavity can be filled with a potting material. In addition to the function of a mechanical protection of the semiconductor chip, the potting material can be designed, for example, to modify electromagnetic radiation. However, the semiconductor component does not have to be formed as a cavity component. Alternatively, the semiconductor chip can be embedded completely in the housing material, for example.In one embodiment, the solder control structure and / or the further solder control structure has a metallic coating in the region of the recess or the further recess. Advantageously, wetting properties of the solder control structure and / or of the further solder control structure can thereby be improved.A method for producing a semiconductor component comprises the following method steps. A lead frame composite is embedded in a housing body composite. The leadframe assembly includes a plurality of first contact pads, a plurality of second contact pads, and a plurality of solder control features. The first and second contact pads and the solder control structure elements are connected to one another in the leadframe assembly via connecting webs. The solder control features have recesses. Semiconductor chips are arranged on the leadframe assembly, wherein in each case one semiconductor chip is electrically connected to a first and second contact pad. The leadframe assembly and the housing body assembly are singulated into separate semiconductor devices. In each case, a semiconductor chip, the first and second contact pads electrically connected to the semiconductor chips and in each case a solder control structure are arranged in a common housing produced by singulating the housing body composite. The separation takes place in regions of the connecting webs and the recesses of the solder control structure elements, whereby the solder control structure elements are divided into solder control structures with recesses for receiving a solder material, which recesses are accessible on mounting surfaces and in each case at least one side wall of the housings, and the contact pads and the solder control structures are separated from one another.In one embodiment, before embedding the leadframe assembly in the package body assembly, a sacrificial material is arranged in the recesses of the solder control structure elements. Sacrificial material remaining in the recesses may be removed after the singulation. This protects the solder control structures from being covered with the package material. In addition, the solder control structures are protected by the sacrificial material during the division in the region of the recesses, as a result of which damage to a metallic coating can be prevented, for example.In one embodiment, first contact pads are connected to one another via first connecting webs in the leadframe assembly. Second contact pads are connected to one another via second connecting webs. The first and the second connecting webs are arranged parallel to one another. In each case a first contact pad is connected to in each case a second contact pad via third connecting webs. The third connecting webs are arranged perpendicular to the first and second connecting webs. In each case, a solder control structure element is arranged between two adjacent first contact pads. The solder control structural elements are each connected to one another via fourth connecting webs. The fourth connecting webs are arranged parallel to the third connecting webs. The separation takes place in the region of the solder control structure elements along the fourth connecting webs and in the region of the third connecting webs perpendicularly to the third connecting webs. This allows solder control structures to be created which are accessible on the side walls of the housing.In one embodiment, first contact pads are connected to one another via first connecting webs in the leadframe assembly. In each case a first contact pad is connected to in each case a second contact pad via third connecting webs.The third connecting webs are arranged perpendicular to the first connecting webs. A first and a second contact pad are each laterally surrounded by four solder control structure elements. The solder control structural elements are connected to one another via fourth and fifth connecting webs, respectively. The fourth connecting webs are arranged parallel to the third connecting webs. The fifth connecting webs are arranged perpendicular to the third and fourth connecting webs. The separation takes place in the region of the solder control structure elements along the fourth and fifth connecting webs and in the region of the third connecting webs perpendicularly to the third connecting webs. This allows solder control structures to be produced which are accessible at the housing corners.In one embodiment, first contact pads are connected to one another via first connecting webs in the leadframe assembly. Second contact pads are connected to one another via second connecting webs. The first and the second connecting webs are arranged parallel to one another. In each case a first contact pad is connected to in each case a second contact pad via third connecting webs. The third connecting webs are arranged perpendicular to the first and second connecting webs. In each case, a solder control structure element is arranged between two adjacent first contact pads or between a first and second contact pad and between the third connecting webs. A respective solder control structure element is connected via a sixth connecting web to a respective first contact pad or via an eighth connecting web to a respective second contact pad. The sixth connecting webs are arranged parallel to the first and second connecting webs and the eighth connecting webs are arranged parallel to the third connecting webs. In each case a first contact pad is connected to in each case a further second contact pad via seventh connecting webs. The seventh connecting webs are arranged transversely to the first and third connecting webs. The separation takes place in the region of the solder control structure elements and in regions of the first, second and seventh connecting webs perpendicularly to the first and second connecting webs and in regions of the third connecting webs perpendicularly to the third connecting webs. Advantageously, in this embodiment, less material of the lead frame assembly is located in the region of singulating planes, for example in the region of saw tracks.The above-described characteristics, features and advantages of this invention and the manner in which these are achieved become clearer and more clearly comprehensible in conjunction with the following description of the exemplary embodiments, which are explained in more detail in conjunction with the drawings. The following are shown: FIG. 1 : shows a semiconductor component according to an exemplary embodiment in a transparent side view and a bottom view; FIG. 2 shows a self-alignment of the semiconductor component in the context of surface mounting in a plan view; FIG. 3 : parts of the semiconductor component of FIG. 1 and of a known semiconductor component in comparison in a transparent bottom view; FIG. 4 : various embodiments of semiconductor components with anchored solder control structures in a transparent bottom view; FIG. 5 : a first lead frame assembly for producing a semiconductor component in a transparent bottom view; FIG. 6 : shows a second leadframe assembly for producing a semiconductor component in a transparent bottom view; FIG. 7 : shows a third lead frame assembly for producing a semiconductor component in a transparent bottom view; FIG. 8 : shows a fourth lead frame assembly for producing a semiconductor component in a transparent bottom view.FIG. 1 schematically shows a semiconductor component 1 according to an exemplary embodiment in a transparent side view on the left side and a transparent bottom view on the right side.The semiconductor component 1 has a lead frame 2. The leadframe 2 comprises copper, for example. The lead frame 2 may also comprise another metallic material. Optionally, the lead frame 2 may have a coating, for example an anti-corrosion coating. The lead frame 2 has an upper side 3 and a lower side 4 opposite the upper side 3.The semiconductor component 1 further comprises a housing 5. The housing 5 is shown partially transparent in FIG. 1 in order to represent elements located in the housing 5. The housing 5 has, in the view of FIG. 1, a rectangular cross section by way of example. The housing 5 can, however, also have other geometric cross sections. The housing 5 comprises an epoxy resin by way of example, but it can also comprise a silicone or another molding material or housing material, for example. The lead frame 2 is embedded in the case 5. The embedding of the leadframe 2 in the housing 5 can be effected, for example, by means of a molding method, for example by means of injection molding, in particular by means of film-assisted injection molding (FAM for short).The housing 5 has a mounting surface 6. The lead frame 2 is embedded in the housing 5 in such a way that the upper side 3 of the lead frame 2 is facing away from the mounting surface 6. The underside 4 of the leadframe 2 terminates flush with the mounting surface 6, which is not absolutely necessary, however.The leadframe 2 has at least two electrical contact pads 7, 8. The semiconductor component 1 also has a semiconductor chip 13. The semiconductor chip 13 is arranged in the housing 5 and electrically connected to the contact pads 7, 8. The semiconductor chip 13 is not shown in FIG. 1 for the sake of simplicity. The contact pads 7, 8 are formed, for example, rectangular with rounded corners. However, the contact pads 7, 8 can also be shaped differently.The semiconductor component 1 can be formed, for example, as a cavity component. In this case, the housing 5 has a cavity 12. The contact pads 7, 8 are not covered by the housing material at least in sections and are exposed at a bottom of the cavity 12. The base of the cavity 12 is arranged running parallel to the mounting surface 6 and can end flush with the upper side of the leadframe 2, which is not obligatory, however. The cavity 12 extends from the upper side 3 of the leadframe 2 as far as a side of the housing 5 facing away from the mounting surface 6.The semiconductor chip 13 is arranged at the bottom of the cavity 12. The semiconductor chip 13 can have, for example, contact surfaces on its underside facing the contact pads 7, 8, which are each connected to a contact pad 7, 8 of the leadframe 2 via a solder material, wherein the semiconductor chip 13 is arranged on or over both contact pads 7, 8. The semiconductor chip 13 can alternatively have, for example, further contact pads on its upper side facing away from the contact pads 7, 8, which pads are each connected to a contact pad 7, 8 of the leadframe 2 via a bonding wire. In another embodiment, the semiconductor chip 13 may have a contact surface on its underside and a further contact surface on its upper side, be arranged on or on a first contact pad 7 and be connected via a solder material to the first contact pad 7 and via a bond wire to a second contact pad 8.The lead frame 2 has, for example, two solder control structures 9 each having a recess 11 for receiving a solder material, which recess is accessible on the mounting surface 6 and at least one side wall 10 of the housing 5. It may also be sufficient if the leadframe 2 or the semiconductor component 1 has only one solder control structure 9. However, the semiconductor component 1 or the leadframe 2 of the semiconductor component 1 can also have any desired number of solder control structures 9.By way of example, the solder control structures 9 are arranged on mutually opposite side walls 10 of the housing 5. Alternatively or additionally, the solder control structures 9 can be arranged in the region of housing corners 12. However, the solder control structures 9 can also be arranged differently, for example on adjacent side walls 10 of the housing 5.The solder control structures 9 make the semiconductor component 1 surface-mountable. FIG. 2 schematically illustrates a self-alignment of the semiconductor component 1 in the context of surface mounting in a plan view. Reference numerals used so far are retained below. FIG. 2 shows, by way of example, the semiconductor chip 13 arranged in the cavity 12. However, the cavity 12 can be omitted, as has already been explained.The main purpose of solder control structures 9 is often not a control as to whether a soldering process has been carried out reliably, but rather in the fact that the semiconductor component 1 can align itself, for example, independently with solder contact pads by the solder control structures 9. FIG. 2 shows an exemplary scenario on the left, in which the semiconductor component 1 has been arranged on a printed circuit board 14. The printed circuit board 14 has orientation marks 15. By way of example, the printed circuit board 14 has four alignment marks 15 which are arranged in a rectangular manner and serve to indicate a correct position of the semiconductor component 1. However, the solder control structures 9 cannot be seen in FIG. 2 since the housing 5 is shown in plan view and not transparently. The printed circuit board 14 also has solder contact pads, which are likewise not recognizable in FIG. 2, since they are arranged between the semiconductor component 1 and the printed circuit board 14. The printed circuit board 14 expediently has a number of solder contact pads corresponding to the number of solder control structures 9 of the semiconductor component 1.The formation of a solder meniscus on the solder control structures 9 exerts a force on the semiconductor component 1 by a surface tension of the liquid solder material. As a result, the semiconductor component 1 aligns itself independently on the printed circuit board 14 with respect to the solder contact pads during surface mounting. The self-alignment may comprise an azimuthal rotation and / or a translation of the semiconductor component 1. FIG. 2 shows the aligned semiconductor component 1 on the right side after it has not been correctly arranged beforehand on the printed circuit board 14, which is shown on the left side.FIG. 3 schematically shows parts of the semiconductor component 1 of FIG. 1 and of a known semiconductor component 16 in comparison in a transparent bottom view. The semiconductor component 16 according to the prior art is shown on the left side, while the semiconductor component 1 according to the exemplary embodiment of FIG. 1 is shown on the right side. For the known semiconductor device, the same reference numerals are used for similar elements.In contrast to previous semiconductor components 16, in the half-conductor component 1, the contact pads 7, 8 and the solder control structures 9 are formed by separate and discontinuous sections of the leadframe 2. In the case of previously known semiconductor components 16, on the other hand, solder control structures 16 are firmly connected to one of the contact pads 7, 8 or are formed by a common section of the leadframe 2.It is problematic that, in the case of mechanical loads, for example in the production during the separation of a plurality of semiconductor components 1, during handling, during testing, during the surface mounting of the semiconductor components 1 etc. and by thermomechanical stress, for example caused by different thermal expansion coefficients between the housing 5 and the printed circuit board 14, a mechanical stress distribution can be effected which has a concentration or concentration of stresses in the region of the solder control structures 9 when the solder control structures 9 are firmly connected to the contact pads 7, 8.FIG. 3 illustrates this circumstance on the basis of voltage lines or voltage trajectories, which can also be referred to as isoclyne. In previously known semiconductor components 16, the concentration of stresses is effected in the region of the solder control structures 9. This is indicated in FIG. 3 by dense stress lines. In this way, cracks can be produced in the housing 5. The cracks can form in particular in the region of the solder control structures 9 and can propagate in the housing 5, as a result of which the housing 5 can break. In the present semiconductor component 1, on the other hand, a certain voltage flow is made possible, since the solder control structures 9 are not connected to the contact pads 7, 8 and are embodied as separate sections of the leadframe 2. This prevents excessive concentration of stresses. In FIG. 3, the voltage lines in the present semiconductor component 1 are therefore shown less dense than in the known semiconductor component 16. Cracks and fractures in the housing 5 can thus be reduced or prevented.FIG. 4 schematically shows various embodiments of semiconductor components 1 with anchored solder control structures 9 in a transparent bottom view. As in FIG. 1, the housing 5 is shown transparent in each case in such a way that the contact pads 7, 8 can be seen. The semiconductor components 1 of FIG. 4 have similarities to the semiconductor component 1 of FIG. 1. Similar or identical elements are provided with the same reference numerals. The differences between the semiconductor components 1 of FIG. 4 and the semiconductor component 1 of FIG. 1 are substantially explained below.All three embodiments of the semiconductor components 1 shown in FIG. 4 have in common that they have solder control structures 9 with anchorings 17 embedded in the housing 5. By way of example, each solder control structure 9 has two anchorings 17 in each case. It may also be sufficient if each solder control structure 9 has only one anchoring 9. Alternatively, more than two anchorings 17 per solder control structure 9 can also be provided. Likewise by way of example, the anchorings 17 of the solder control structures 9 of a semiconductor component 1 in each case are of different design. In general, the anchorings 17 of a semiconductor component 1 can, however, also be embodied identically for all solder control structures 9. Not all solder control structures 9 of a semiconductor component 1 need have an anchoring 17. The anchorings 17 however offer the advantage that the solder control structures 9 are better connected to the housing 5. This may be necessary, since a mechanical stability of the solder control structures 9 may be reduced due to the separation from the contact pads 7, 8.FIG. 4 shows, on the left-hand side, a semiconductor component 1 having solder control structures 9, the exemplary anchorings 17 of which are beam-shaped and each project from the solder control structures 9 in a direction parallel to the mounting surface 6. In this case, first anchorings 17 of a first solder control structure 9 are arranged tangentially at corners of the first solder control structure 9, and second anchorings 17 of a second solder control structure 9 are arranged protruding from corners of the second solder control structure 9 and running substantially parallel to side walls 10 of the housing 5. The first anchorings 17 are thus arranged transversely to the second anchorings 17. In addition, the second anchorings 17 are longer than the first anchorings 17, but they can also be of the same length and of the same orientation, for example.The semiconductor component 1 shown in the middle of FIG. 4 has, by way of example, a third solder control structure 9 with two third anchorings 17 and a fourth solder control structure 9 with a fourth anchoring 17. The third anchorings 17 are substantially formed like the second anchorings 17 of the second solder control structure 9 of the semiconductor component 1 shown on the left-hand side, but are significantly shorter.The fourth anchoring 17 of the fourth solder control structure 9 is beam-shaped and arranged parallel to a side wall 10 of the housing 5. However, the fourth anchor 17 does not extend directly from a corner or side surface of the fourth solder control structure 9. Instead, the fourth solder control structure 9 has a connecting element 18 connected to the fourth anchoring 17. The connecting element 18 extends, for example, from a side surface of the fourth solder control structure 9 and is arranged perpendicular to the side surface of the fourth solder control structure 9 and to the fourth anchoring 17. As a result, the fourth anchoring 17 and the connecting element 18 are arranged in a T-shaped manner and are embedded or anchored in the housing material, as a result of which a particularly reliable anchoring of the fourth solder control structure 9 in the housing 5 is ensured.FIG. 4 shows, on the right side, an exemplary semiconductor component 1 having a fifth solder control structure 9 having two fifth anchors 17 and a sixth solder control structure 9 having two sixth anchors 17. the sixth anchors 17 are formed substantially like the fourth anchor 17 of the fourth solder control structure 9 of the semiconductor component 1 shown in the middle, but they do not extend from a side face of the sixth solder control structure 9 but respectively from a corner of the sixth solder control structure 9, such that the anchors 17 are arranged transversely to the side faces 10 of the housing. The fifth anchors 17 are formed similarly to the second anchors 17, but the fifth anchors 17 are additionally formed curved and have a bead at their ends. All anchorings 17 can also extend in a direction perpendicular to the mounting surface 6 of the housing 5.Method steps of a method for producing a semiconductor component 1 are explained below. FIGS. 5 to 8 each show a leadframe assembly 19, 20, 21, 22 for producing a plurality of semiconductor components 1 in a transparent bottom view. In this case, a housing body composite or the housings 5 is in each case completely transparent. The semiconductor chips are not shown in FIGS. 5 to 8 for clarity. Reference numerals used so far are retained below.FIGS. 5 to 8 each show a state after carrying out a first method step, in the course of which a lead frame composite 19, 20, 21, 22 has been embedded in a housing body composite. The embedding of the leadframe assembly 19, 20, 21, 22 can be effected, for example, by means of a molding method, for example by means of FAM.A first leadframe assembly 19 shown in FIG. 5 is suitable for producing semiconductor components 1 according to FIG. 1. the first leadframe assembly 19 comprises a plurality of first contact pads 7, a plurality of second contact pads 8 and a plurality of solder control structure elements 23.The first, the second contact pads 7, 8 and the solder control structure elements 9 are initially connected to one another in the first leadframe assembly 19 via connecting webs. The solder control features 23 have recesses 24.Within the scope of a second method step, semiconductor chips are arranged on the first lead frame assembly 19. In this case, a semiconductor chip is electrically connected to a first and second contact pad 7, 8, respectively. The semiconductor chips can be arranged on the first leadframe assembly 19, for example, after embedding the first leadframe assembly 19 in the package body assembly, for example, by arranging the semiconductor chips in the cavities 12 of the packages 5. However, the semiconductor chips can also be arranged on the first lead frame assembly 19 before embedding the first lead frame assembly 19 in the housing body assembly.In the context of a third method step, the first leadframe assembly 19 and the housing body assembly are separated into separate semiconductor components 1. FIGS. 5 to 8 each show singulating planes 25 which extend perpendicularly to the conductor track plane or perpendicularly to the mounting surfaces 6 of the housings 5 to be produced. The singulating takes place along the singulating planes 25.In each case, a semiconductor chip, the first and second contact pads 7, 8 electrically connected to the semiconductor chips and two solder control structures 9 are arranged in a common housing 5 produced by singulating the housing body composite. The separation takes place in the regions of the connecting webs and the recesses 24 of the solder control structure elements 23, as a result of which the solder control structure elements 23 are divided into solder control structures 9 with recesses 11 for receiving a solder material, which recesses are accessible on mounting surfaces 6 and in each case at least one side wall 10 of the housings 5, and the contact pads 7, 8 and the solder control structures 9 are separated from one another.In the first leadframe assembly 19, first contact pads 7 are connected to one another via first connecting webs 26. Second contact pads 8 are connected to one another via second connecting webs 27. The first and the second connecting webs 26, 27 are arranged parallel to one another. A first contact pad 7 is connected to a second contact pad 8 via third connecting webs 28. By way of example, two third connecting webs 28 respectively connect a first and a second contact pad 7, 8 to one another. The third connecting webs 28 are arranged perpendicular to the first and second connecting webs 26, 27.In each case, a solder control structure element 23 is arranged between two adjacent first contact pads 7. The solder control structural elements 23 are each connected to one another via fourth connecting webs 29. The fourth connecting webs 29 are arranged parallel to the third connecting webs 28 and perpendicular to the first and second connecting webs 26, 27 and cross the first and second connecting webs 26, 27.The singulating of the first lead frame assembly 19 and the housing body assembly takes place in the region of the solder control structure elements 23 along the fourth connecting webs 29 and in the region of the third connecting webs 28 perpendicularly to the third connecting webs 28. Because the fourth connecting webs 29 connect the solder control structural elements 23 to one another, the solder control structural elements 23 are halved. For each semiconductor component 1, two mutually opposite solder control structures 9 are formed with recesses 11 which are accessible on the mounting surfaces 6 and side walls 10 of the housings 5, since in each case one solder control structure element 23 is arranged between two adjacent first contact pads 7.The first, second and third connecting webs 26, 27, 28 can be exposed and accessible on the side walls 10 of the housings 5 after separation. By way of example, FIG. 5 shows that the first leadframe assembly 19 has a smaller thickness in the region of the connecting webs 26, 27, 28, 29 than in the region of the contact pads 7, 8, wherein the contact pads 7, 8 also have a smaller thickness in edge regions, by way of example, than in their remaining regions. Because the connecting webs have a smaller thickness, the separation can be simplified.FIG. 6 schematically shows an exemplary second leadframe assembly 20 suitable for producing semiconductor components 1 having a total of four respective solder control structures 9, which are each arranged in housing corners. The second lead frame assembly 20 has similarities to the first lead frame assembly 19. Differences of the second lead frame assembly 20 from the first lead frame assembly 19 are substantially explained below. Reference numerals are retained for similar or identical elements.The second leadframe assembly 19 likewise has a plurality of first contact pads 7, a plurality of second contact pads 8 and a plurality of solder control structure elements 23, which are initially connected to one another via connecting webs. In the second leadframe assembly 20, first contact pads 7 are connected to one another via first connecting webs 26. The second contact pads 8, on the other hand, are not connected to one another via second connecting webs 27. The second connecting webs 27 are therefore omitted in the case of the second leadframe assembly 20. By way of example, two third connecting webs 28 respectively connect a first and a second contact pad 7, 8 to one another. The third connecting webs 28 are arranged perpendicular to the first connecting webs 26.In each case a first and a second contact pad 7, 8, i.e. in each case a pair of first and second contact pads 7, 8, are laterally surrounded by four solder control structure elements 23. The solder control structure elements 23 are connected to one another in the case of the second leadframe assemblage 20 as in the case of the first leadframe assemblage 19 in each case via fourth connecting webs 29. The fourth connecting webs 29 are arranged parallel to the third connecting webs 28 and perpendicular to the first connecting webs 26 and cross the first connecting webs 26. The fifth connecting webs 30 are arranged perpendicular to the third and fourth connecting webs 28, 29.The singulating of the second leadframe assembly 19 and of the housing body assembly takes place in the region of the solder control structure elements 23 along the fourth and fifth connecting webs 29, 30 and in the region of the third connecting webs 28 perpendicularly to the third connecting webs 28. Because the fourth and fifth connecting webs 29, 30 connect the solder control structural elements 23 to one another, the solder control structural elements 23 are corrugated during the separation. Four solder control structures 9 are formed per semiconductor component 1, which are each arranged in a housing corner, since the fourth and fifth connecting webs 29, 30 cross in the region of the solder control structure elements 23. In other words, the separating planes 25 in this case run parallel to the fourth and fifth connecting webs 29, 30.FIG. 7 schematically shows an exemplary third leadframe assembly 21 suitable for producing further semiconductor components 1. The third lead frame assembly 21 has similarities to the first lead frame assembly 19. Differences of the third lead frame assemblage 21 from the first lead frame assemblage 19 are substantially explained below. Reference numerals are retained for similar or identical elements.The third lead frame assembly 21, like the first lead frame assembly 19, has the first, second and third connecting webs 26, 27, 28. Likewise, a respective solder control structure element 23 is arranged between two adjacent first contact pads 7. The fourth and fifth connecting webs 29, 30 are omitted in the case of the third leadframe assembly 21, and the solder control structure elements 23 are each connected via sixth connecting webs 31 to a respective first contact pad 7. The sixth connecting webs 31 are arranged parallel to the first and second connecting webs 26, 27. In each case, a first contact pad 7 is connected to in each case a further second contact pad 8 via seventh connecting webs 32. The seventh connecting webs 32 are arranged transversely to the first and third connecting webs 26, 28. The separation takes place in the region of the solder control structural elements 23 and in regions of the first, second and seventh connecting webs 26, 27, 32 perpendicularly to the first and second connecting webs 26, 27, 32 and in regions of the third connecting webs 28 perpendicularly to the third connecting webs 28. As a result, in the case of the third leadframe assembly 21, less metal is located in the region of the singulating planes 25, as a result of which the singulating is simplified.Because the solder control structure elements 23 are connected to the first contact pads 7 via the sixth connecting webs 31, wherein each solder control structure element 23 is connected to only one first contact pad 7 in each case, after the singulating of the third leadframe assembly 21, a solder control structure 9 and a further solder control structure 33 remain having a further recess 34 for receiving a solder material in the semiconductor component 1, said further recess being accessible at least on the mounting surface 6 of the housing 5.The further solder control structures 33 are firmly connected to the first contact pads 7. The further solder control structures 33 and the first contact pads 7 are therefore also formed by a common section of the leadframe 2 after the singulation of the third leadframe assemblage 21. The further recesses 34 of the further solder control structures 33 are also accessible on at least one side wall 10 of the housing 5 in addition to the mounting surface 6. The further solder control structure 33 can alternatively be accessible only on the mounting surface 6. In this case, the sixth connecting webs 31 are omitted, since the further recesses 34 are formed directly below the first contact pads 8.FIG. 8 schematically shows an exemplary fourth leadframe assembly 22 suitable for producing further semiconductor components 1. The fourth lead frame assembly 22 has similarities to the third lead frame assembly 21. Differences of the fourth lead frame assemblage 22 from the third lead frame assemblage 21 are substantially explained below. Reference numerals are retained for similar or identical elements.In contrast to the third lead frame assembly 21, the solder control structure elements 23 in the fourth lead frame assembly 22 are not connected to a first contact pad 7 via sixth connecting webs 31, respectively. Rather, the sixth connecting webs 31 are omitted in the fourth lead frame assembly 22, instead of this, the solder control structure elements 23 are connected to second contact pads 8 via eighth connecting webs 35. The eighth connecting webs 31 are arranged parallel to the third connecting webs 28. In addition, the fourth lead frame assembly 22 has the seventh connecting webs 32 in addition to the first, second and third connecting webs 26, 27, 28, as a result of which less material of the fourth lead frame assembly 22 is located in the region of the singulating planes 25 even in the case of the fourth lead frame assembly 22.The invention has been illustrated and described in more detail with reference to the preferred exemplary embodiments. Nevertheless, the invention is not limited to the disclosed examples. Rather, other variations can be derived from this by the person skilled in the art without departing from the scope of protection of the invention.LIST OF REFERENCE CHARACTERS1 Semiconductor component 2 Leadframe 3 Upper side of the leadframe 4 Lower side of the leadframe 5 Housing 6 Mounting surface of the housing 7 First contact pad 8 Second contact pad 9 Solder control structure 10 Side wall of the housing 11 Recess of the solder control structure 12 Cavity 13 Semiconductor chip 14 Printed circuit board 15 Alignment mark 16 Semiconductor component according to the prior art 17 Anchoring 18 Connecting element for anchoring 19 First leadframe assembly 20 Second leadframe assembly 21 Third leadframe assembly 22 Fourth leadframe assembly 23 Solder control structure elements 24 Recesses of the solder control structure elements 25 Singulating planes 26 First connecting webs 27 Second connecting webs 28 Third connecting webs 29 Fourth connecting webs 30 Fifth connecting webs 31 Sixth connecting webs 32 Seventh connecting webs 33 Further solder control structure 34 Further recess of the further solder control structure 35 Eighth connecting webs

Claims

Semiconductor component (1) having a housing (5) with a mounting surface (6), a lead frame (2) embedded in the housing (5) and having at least two electrical contact pads (7, 8) and at least one semiconductor chip (13) arranged in the housing (5) and electrically connected to the contact pads (7, 8), wherein the lead frame (2) has a solder control structure (9) with a recess (11), which is accessible at the mounting surface (6) and at least one side wall (10) of the housing (5), for receiving a solder material, wherein the contact pads (7, 8) and the solder control structure (9) are formed by separate and discontinuous sections of the lead frame (2).Semiconductor component (1) according to Claim 1, wherein the leadframe (2) has at least two solder control structures (9) having recesses (11), which are accessible at the mounting surface (6) and at least one side wall (10) of the housing (5), for receiving a solder material, wherein the contact pads (7, 8) and the solder control structures (9) are formed by separate and discontinuous sections of the leadframe (2).Semiconductor component (1) according to Claim 2, wherein the solder control structures (9) are arranged on mutually opposite side walls (10) of the housing (5) and / or in the region of corners of the housing (5).Semiconductor component (1) according to one of the preceding claims, wherein the solder control structure (9) has at least one anchoring (17) embedded in the housing (5).Semiconductor component (1) according to Claim 4, wherein the anchoring (17) is of beam-shaped design and protrudes from the solder control structure (9) in a direction parallel to the mounting surface (6).Semiconductor component (1) according to Claim 4 or 5, wherein the solder control structure (9) has a connecting element (18) connected to the anchoring (17).Semiconductor component (1) according to one of the preceding claims, wherein at least one contact pad (7, 8) has a further solder control structure (33) with a further recess (34), which is accessible at least on the mounting surface (6) of the housing (5), for receiving a solder material.Semiconductor component (1) according to one of the preceding claims, wherein the housing (5) has a cavity (12), wherein the contact pads (7, 8) are not covered, at least in sections, by a housing material and are exposed at a base of the cavity (12) arranged parallel to the mounting surface (6), wherein the semiconductor chip (13) is arranged at the base of the cavity (12).Method for producing a semiconductor component (1), having the following method steps: - embedding a leadframe assembly (19, 20, 21, 22) in a package body assembly, wherein the leadframe assembly (19, 20, 21, 22) has a plurality of first contact pads (7), a plurality of second contact pads (8) and a plurality of solder control structure elements (23), wherein the first and the second contact pads (7, 8) and the solder control structure elements (23) in the leadframe assembly (19, 20, 21, 22) are connected to one another via connecting webs (26, 27, 28, 29, 30, 31, 32, 35), wherein the solder control structure elements (23) have recesses (24), - arranging semiconductor chips (13) on the leadframe assembly (19, 20, 21, 22), wherein in each case one semiconductor chip (13) is electrically connected to a first and second contact pad (7, 8), - singulating the leadframe assembly (19, 20, 21, 22), 22) and of the housing body assembly into separate semiconductor components (1), wherein in each case a semiconductor chip (13), the first and second contact pads (7, 8) electrically connected to the semiconductor chips (13) and in each case a solder control structure (9) are arranged in a common housing (5) produced by the singulating of the housing body assembly, wherein the singulating takes place in regions of the connecting webs (26, 27, 28, 29, 30, 31, 32, 35) and of the recesses (24) of the solder control structure elements (23), as a result of which the solder control structure elements (23) are divided into solder control structures (9) having recesses (11) for receiving a solder material which are accessible at mounting surfaces (6) and in each case at least one side wall (10) of the housings (5) and the contact pads (7, 8) and the solder control structures (9) are separated from one another.Method according to claim 9, wherein before embedding the lead frame composite (19, 20, 21, 22) in the housing body composite, a sacrificial material is arranged in the recesses (24) of the solder control structure elements (23).Method according to Claim 9 or 10, wherein in the leadframe assembly (19), first contact pads (7) are connected to one another via first connecting webs (26), wherein second contact pads (8) are connected to one another via second connecting webs (27), wherein the first and the second connecting webs (26, 27) are arranged parallel to one another, wherein in each case a first contact pad (7) is connected to in each case a second contact pad (8) via third connecting webs (28), wherein the third connecting webs (28) are arranged perpendicularly to the first and second connecting webs (26, 27), wherein in each case a solder control structure element (23) is arranged between two adjacent first contact pads (7, 8), wherein the solder control structure elements (23) are in each case connected to one another via fourth connecting webs (29), wherein the fourth connecting webs (29) are arranged parallel to the third connecting webs (28), wherein the separation takes place in the region of the solder control structural elements (23) along the fourth connecting webs (29) and in the region of the third connecting webs (28) perpendicular to the third connecting webs (28).Method according to Claim 9 or 10, wherein in the leadframe assembly (20), first contact pads (7) are connected to one another via first connecting webs (26), wherein in each case a first contact pad (7) is connected to in each case a second contact pad (8) via third connecting webs (28), wherein the third connecting webs (28) are arranged perpendicular to the first connecting webs (26), wherein in each case a first and a second contact pad (7, 8) are laterally surrounded by four solder control structure elements (23), wherein the solder control structure elements (23) are in each case connected to one another via fourth and fifth connecting webs (29, 30), wherein the fourth connecting webs (29) are arranged parallel to the third connecting webs (28), wherein the fifth connecting webs (30) are arranged perpendicular to the third and fourth connecting webs (28, 29), wherein the singulation in the region of the solder control structure elements (23) along the fourth and fifth connecting webs (29, 29), 30) and in the region of the third connecting webs (28) perpendicular to the third connecting webs (28).Method according to claim 9 or 10, wherein in the leadframe assembly (21, 22), first contact pads (7) are connected to one another via first connecting webs (26), wherein second contact pads (8) are connected to one another via second connecting webs (27), wherein the first and the second connecting webs (26, 27) are arranged parallel to one another, wherein in each case a first contact pad (7) is connected to in each case a second contact pad (8) via third connecting webs (28), wherein the third connecting webs (28) are arranged perpendicular to the first and second connecting webs (26, 27), wherein in each case a solder control structure element (23) is arranged between two adjacent first contact pads (7) or between a first and a second contact pad (7, 8) and between the third connecting webs (28), wherein a respective solder control structural element (23) is connected via a sixth connecting web (31) to a respective first contact pad (7) or via an eighth connecting web (35) to a respective second contact pad (8), wherein the sixth connecting webs (31) are arranged parallel to the first and second connecting webs (26, 27) and the eighth connecting webs (35) are arranged parallel to the third connecting webs (28), wherein a respective first contact pad (7) is connected to a respective further second contact pad (8) via seventh connecting webs (32), wherein the seventh connecting webs (32) are arranged transversely to the first and third connecting webs (26, 28), wherein the separation is carried out in the region of the solder control structural elements (23) and in regions of the first, second and seventh connecting webs (26, 27, 32) perpendicularly to the first and second connecting webs (26, 27, 32), 27) and in regions of the third connecting webs (28) perpendicular to the third connecting webs (28).

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