Semiconductor component and method for producing a semiconductor component

Abstract

The invention relates to a semiconductor component (1) comprising: a housing (5) having a mounting face (6); a lead frame (2) which is embedded in the housing (5) and has at least two electrical contact pads (7, 8); and at least one semiconductor chip (13) which is located in the housing (5) and is electrically connected to the contact pads (7, 8). The lead frame (2) has a solder control structure (2) having a recess (11) which is accessible from the mounting face (6) and at least one side wall (10) of the housing (5) and is provided for receiving a solder material. The contact pads (7, 8) and the solder control structure (9) are formed by separate and non-connected portions of the lead frame (2).

Description

[0001] SEMICONDUCTOR COMPONENT AND METHOD FOR PRODUCING ONE

[0002] SEMICONDUCTOR COMPONENTS

[0003] DESCRIPTION

[0004] The present invention relates to a semiconductor device and a method for producing a semiconductor device.

[0005] This patent application claims priority from German patent application DE 10 2023 127 271 . 3 , the disclosure of which is hereby incorporated by reference.

[0006] Surface-mount optoelectronic components with solder control structures for receiving a solder material are known from the prior art. Among other things, the solder control structures enable self-alignment of the optoelectronic components with respect to solder contact pads, for example, with respect to solder contact pads on a printed circuit board (PCB).

[0007] A disadvantage of previously known optoelectronic components with solder control structures is that mechanical stress causes tension in the component. This can lead to cracks and fractures in the component's housing.

[0008] An object of the present invention is 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 respective independent claims. Advantageous further developments are specified in the dependent claims.

[0009] A semiconductor component comprises 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 unconnected sections of the lead frame.

[0010] The semiconductor component can be designed, for example, as an optoelectronic component. In this case, it comprises at least one optoelectronic semiconductor chip. The optoelectronic semiconductor chip can be designed, for example, to emit electromagnetic radiation. In this case, the at least one optoelectronic semiconductor chip can be designed as a light-emitting diode (LED) or, for example, as a laser diode.

[0011] The optoelectronic component can have a plurality of optoelectronic semiconductor chips. For example, it can have three light-emitting diodes and be designed, for example, as an RGB light-emitting diode that is configured to emit light in the colors red, green, and blue. In this case, the optoelectronic component can be designed as a pixel element of a display device. However, the optoelectronic component can also be designed, for example, as a LiDAR device (light detection and ranging, or LiDAR for short). In this case, the at least one semiconductor chip is designed as a laser diode.

[0012] The at least one optoelectronic semiconductor chip can alternatively also be designed to detect electromagnetic radiation, for example the optoelectronic semiconductor chip can be designed as a photodiode.

[0013] However, the semiconductor component does not necessarily have to be an optoelectronic component. It can also be an electronic component with at least one electronic semiconductor chip. The electronic semiconductor chip can be any integrated circuit (IC for short).

[0014] In another embodiment, the semiconductor component can also be embodied as a microelectromechanical component with a microelectromechanical semiconductor chip. A microelectromechanical semiconductor chip can be embodied, for example, as a pressure sensor, an acceleration sensor, or another sensor.

[0015] The semiconductor component can, for example, be designed as a so-called QFN component (quad flat no leads package, or QFN package for short). A QFN component is characterized by the fact that electrical connections connected to the contact pads do not protrude beyond the housing of the semiconductor component, but are only accessible or exposed 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 of being particularly compact and therefore space-saving.

[0016] The solder control structure means that the semiconductor component is designed as a surface mount device (SMD for short), i.e. the semiconductor component can be mounted on a printed circuit board (PCB), for example, using solder material for fastening. For this purpose, the solder material is arranged, for example, on solder contact pads of the 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 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 make electrical contact with the semiconductor chip.One idea underlying the semiconductor component is to separate the solder control structure from other leadframe components. For this reason, the solder control structure is designed as a separate component of the leadframe from the electrical contact pads. In other words, the solder control structure and the contact pads are not connected to one another. Advantageously, this can significantly reduce the concentration of mechanical stress on the solder control structures. In comparison, in previously known designs of surface-mount semiconductor components, the electrical contact pads are firmly connected to the solder control structures. In other words, the contact pads and the solder control structures in previously known semiconductor components are formed by common and connected sections of the leadframe.

[0017] Mechanically separating the solder control structure from the other parts of the lead frame can be advantageous in several respects. For example, the housing, which can be manufactured using injection molding, is mechanically more stable because stresses are not concentrated on the solder control structure. Cracks and fractures in the housing can thus be advantageously avoided. Since the mechanical requirements for the housing material are lower, housing materials that are advantageous in respects other than mechanical stability can also be considered.

[0018] Because the solder control structure is separate from the contact pads and not electrically connected to them, it is potential-free and can be referred to as a floating mass. This offers the advantage that several semiconductor components can be arranged particularly close to one another without having to fear short circuits. Furthermore, the lateral positioning of the solder control structure with respect to the mounting surface of the housing can be selected more freely than in the case of a solder control structure that is permanently connected to a contact pad. In one embodiment, the lead frame has at least two solder control structures with recesses 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 structures are formed by separate and unconnected sections of the lead frame.

[0019] Advantageously, the semiconductor component aligns itself automatically into a desired azimuthal orientation, for example during assembly on a printed circuit board. This orientation is essentially predetermined by the solder contact pads of the printed circuit board. If the semiconductor component is arranged with the solder control structures azimuthally offset to the solder contact pads, forces act on the semiconductor component which are essentially determined by interfacial energies at the interfaces between the solder control structures and the solder material, between the solder material and the solder contact pads, and between the solder material and an area surrounding the semiconductor component. These interfacial forces cause an effective torque which acts on the housing, causing it to align until an energetically stable configuration is achieved.This is the case when the solder control structures of the semiconductor component are arranged directly above the solder contact pads of the circuit board.

[0020] In one embodiment, the solder control structures are arranged on opposite side walls of the housing and / or in the region of the housing corners. Advantageously, the arrangement of the solder control structures on opposite side walls of the housing and / or in the region of the housing corners results in particularly effective self-alignment of the semiconductor component during surface mounting.

[0021] The mechanical separation of the at least one solder control structure from the remaining parts of the lead frame, i.e. from the electrical contact pads or chip contact pads, increases the risk that the solder control structure will be torn out of the housing when a lead frame assembly or a housing body assembly is separated during the manufacture of a plurality of semiconductor components. This can advantageously be counteracted by mechanical anchoring. For this reason, in one embodiment, the solder control structure has at least one anchor embedded in the housing.

[0022] 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 particularly reliably in the housing.

[0023] In one embodiment, at least one contact pad has a further solder control structure with a further recess, 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 therefore formed by a common section of the lead frame. The further recess of the further solder control structure can be accessible on at least one side wall of the housing in addition to the mounting surface. The further solder control structure can be firmly mechanically connected to the chip contact pad via a connecting web of the lead frame.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.

[0024] In one embodiment, the housing has a cavity.

[0025] The contact pads are at least partially not covered by a housing material and are exposed at a bottom of the cavity arranged parallel to the mounting surface. The semiconductor chip is arranged at the bottom of the cavity. Advantageously, the cavity can be filled with a potting material. In addition to the function of mechanically protecting the semiconductor chip, the potting material can be designed, for example, to modify electromagnetic radiation. However, the semiconductor component does not have to be designed as a cavity component. Alternatively, the semiconductor chip can, for example, be completely embedded in the housing material.

[0026] 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. This advantageously improves the wetting properties of the solder control structure and / or the further solder control structure.

[0027] A method for producing a semiconductor component comprises the following method steps: A leadframe assembly is embedded in a housing body assembly. The leadframe assembly has a plurality of first contact pads, a plurality of second contact pads and a plurality of solder control structure elements. 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 structure elements have recesses. Semiconductor chips are arranged on the leadframe assembly, one semiconductor chip in each case being electrically connected to a first and second contact pad. The leadframe assembly and the housing body assembly are singulated into separate semiconductor components.One semiconductor chip, the first and second contact pads electrically connected to the semiconductor chips, and one solder control structure are each arranged in a common housing created by singulating the housing body assembly. The singulation 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 accessible on mounting surfaces and at least one side wall of the housing for receiving a solder material, and the contact pads and the solder control structures are separated from one another.

[0028] In one embodiment, a sacrificial material is arranged in the recesses of the solder control structure elements before embedding the leadframe assembly in the package body assembly. Any sacrificial material remaining in the recesses can be removed after singulation. This protects the solder control structures from being covered by the package material. Furthermore, the sacrificial material protects the solder control structures in the region of the recesses during dicing, which can prevent, for example, damage to a metallic coating.

[0029] In one embodiment, in the lead frame assembly, first contact pads are connected to one another via first connecting webs. Second contact pads are connected to one another via second connecting webs. The first and second connecting webs are arranged parallel to one another. In each case, a first contact pad is connected to 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 structure elements are in each case connected to one another via fourth connecting webs. The fourth connecting webs are arranged parallel to the third connecting webs. The singulation 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 perpendicular to the third connecting webs.This makes it possible to create solder control structures that are accessible on the side walls of the housing. In one embodiment, first contact pads in the lead frame assembly are connected to one another via first connecting webs. A first contact pad is each connected to 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 structure elements are each connected to one another via fourth and fifth connecting webs. 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.Separation occurs in the area of ​​the solder control structure elements along the fourth and fifth connecting bars, and in the area of ​​the third connecting bars perpendicular to the third connecting bars. This allows the creation of solder control structures that are accessible at the housing corners.

[0030] In one embodiment, in the leadframe assembly, first contact pads are connected to one another via first connecting webs. Second contact pads are connected to one another via second connecting webs. The first and second connecting webs are arranged parallel to one another. In each case, a first contact pad is connected to 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. In each case, a solder control structure element is connected to a first contact pad via a sixth connecting web or to a second contact pad via an eighth connecting web.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 a further second contact pad via seventh connecting webs. The seventh connecting webs are arranged transversely to the first and third connecting webs. The singulation takes place in the region of the solder control structure elements and in regions of the first, second and seventh connecting webs perpendicular to the first and second connecting webs and in regions of the third connecting webs perpendicular to the third connecting webs. Advantageously, in this embodiment there is less material of the lead frame assembly in the region of singulation planes, for example in the region of saw marks.

[0031] The above-described properties, features, and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more readily understood in connection with the following description of the embodiments, which are explained in more detail in conjunction with the drawings.

[0032] Fig. 1: a semiconductor component according to an exemplary embodiment in a transparent side view and a bottom view;

[0033] Fig. 2: a self-alignment of the semiconductor component in a surface mounting in a plan view;

[0034] Fig. 3: Parts of the semiconductor component of Fig. 1 and a known semiconductor component in comparison in a transparent bottom view;

[0035] Fig. 4: various embodiments of semiconductor components with anchored solder control structures in a transparent bottom view;

[0036] Fig. 5: a first lead frame assembly for producing a semiconductor component in a transparent bottom view;

[0037] Fig. 6: a second leadframe assembly for producing a semiconductor component in a transparent bottom view; Fig. 7: a third leadframe assembly for producing a semiconductor component in a transparent bottom view;

[0038] Fig. 8: a fourth lead frame assembly for producing a semiconductor component in a transparent bottom view.

[0039] Fig. 1 schematically shows a semiconductor device 1 according to an exemplary embodiment in a transparent side view on the left side and a transparent bottom view on the right side.

[0040] The semiconductor component 1 has a lead frame 2. The lead frame 2 is made of copper, for example. The lead frame 2 can also be made of another metallic material. Optionally, the lead frame 2 can have a coating, for example an anti-corrosion coating. The lead frame 2 has a top side 3 and a bottom side 4 opposite the top side 3.

[0041] The semiconductor component 1 further comprises a housing 5.

[0042] The housing 5 is shown partially transparent in Fig. 1 in order to show elements located in the housing 5. The housing 5 has, for example, a rectangular cross-section in the view in Fig. 1. However, the housing 5 can also have other geometric cross-sections. The housing 5 has, for example, an epoxy resin, but it can also have, for example, a silicone or another molding material or housing material. The lead frame 2 is embedded in the housing 5. The embedding of the lead frame 2 in the housing 5 can take place, for example, by means of a molding process, for example by means of injection molding, in particular by means of film-assisted injection molding (FAM for short).

[0043] The housing 5 has a mounting surface 6. The lead frame 2 is embedded in the housing 5 such that the top side 3 of the lead frame 2 faces away from the mounting surface 6. The bottom side 4 of the lead frame 2 is flush with the mounting surface 6, although this is not absolutely necessary.

[0044] The lead frame 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, by way of example, rectangular in shape with rounded corners. However, the contact pads 7, 8 can also have a different shape.

[0045] The semiconductor component 1 can, for example, be designed as a cavity component. In this case, the housing 5 has a cavity 12. The contact pads 7, 8 are at least partially not covered by the housing material and are exposed at a bottom of the cavity 12. The bottom of the cavity 12 is arranged running parallel to the mounting surface 6 and can be flush with the top side of the lead frame 2, although this is not mandatory. The cavity 12 extends from the top side 3 of the lead frame 2 to a side of the housing 5 facing away from the mounting surface 6. For the sake of simplicity, no cavity 12 is shown in Fig. 1.

[0046] The semiconductor chip 13 is arranged at the bottom of the cavity 12. The semiconductor chip 13 can, for example, have contact surfaces on its underside facing the contact pads 7, 8, which are each connected to a contact pad 7, 8 of the lead frame 2 via a solder material, wherein the semiconductor chip 13 is arranged on or above both contact pads 7, 8. Alternatively, the semiconductor chip 13 can, for example, have further contact surfaces on its upper side facing away from the contact pads 7, 8, which are each connected to a contact pad 7, 8 of the lead frame 2 via a bonding wire. In another embodiment, the semiconductor chip 13 can have a contact surface on its underside and a further contact surface on its upper side, can be arranged on or on a first contact pad 7 and can be connected to the first contact pad 7 via a solder material and to a second contact pad 8 via a bonding wire.

[0047] The leadframe 2 has, for example, two solder control structures 9, each with a recess 11 accessible on the mounting surface 6 and at least one side wall 10 of the housing 5 for receiving a solder material. 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 number of solder control structures 9.

[0048] By way of example, the solder control structures 9 are arranged on 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.

[0049] The solder control structures 9 enable the semiconductor component 1 to be surface-mounted. Fig. 2 schematically illustrates a self-alignment of the semiconductor component 1 during surface mounting in a plan view. Previously used reference numerals 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 already explained.

[0050] The main purpose of solder control structures 9 is often not to check whether a soldering process has been carried out reliably, but rather the fact that the semiconductor component 1 can, for example, align itself independently to solder contact pads using the solder control structures 9. Fig. 2 shows on the left-hand side an exemplary scenario 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 orientation marks 15 which are arranged in a rectangular arrangement and serve to indicate a correct position of the semiconductor component 1. The solder control structures 9 cannot, however, be seen in Fig. 2 because the housing 5 is shown in plan view and is not transparent. The printed circuit board 14 also has solder contact pads which are shown in Fig.2 are also not visible 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.

[0051] The formation of a solder meniscus on the solder control structures 9 exerts a force on the semiconductor component 1 due to a surface tension of the liquid solder material. As a result, the semiconductor component 1 aligns itself independently on the circuit board 14 with respect to the solder contact pads during surface mounting. The self-alignment can comprise an azimuthal rotation and / or a translation of the semiconductor component 1. Fig. 2 shows the aligned semiconductor component 1 on the right-hand side, after it had previously been incorrectly arranged on the circuit board 14, which is shown on the left-hand side.

[0052] Fig. 3 shows schematically parts of the semiconductor component 1 of Fig. 1 and 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, while the semiconductor component 1 according to the exemplary embodiment of Fig. 1 is shown on the right. For the known semiconductor component, the same reference numerals are used for similar elements. In contrast to previous semiconductor components 16, in the semiconductor component 1 the contact pads 7, 8 and the solder control structures 9 are formed by separate and unconnected sections of the lead frame 2. In previously known semiconductor components 16, however, solder control structures 16 are firmly connected to one of the contact pads 7, 8 or are formed by a common section of the lead frame 2.

[0053] The problem is that in the case of mechanical loads, for example in production when singulating a plurality of semiconductor components 1, during handling, during testing, during surface mounting of the semiconductor components 1, etc. and due to 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 brought about which has a concentration or bundling of stresses in the area of ​​the solder control structures 9 if the solder control structures 9 are firmly connected to the contact pads 7, 8.

[0054] In Fig. 3 this circumstance is illustrated by means of stress lines or stress trajectories, which can also be referred to as isoclines. In previously known semiconductor components 16 the concentration of stresses is brought about in the region of the solder control structures 9. This is indicated in Fig. 3 by dense stress lines. In this way cracks can arise in the housing 5. The cracks can form in particular in the region of the solder control structures 9 and spread 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 stress flow is made possible because the solder control structures 9 are not connected to the contact pads 7, 8 and are designed as separate sections of the lead frame 2. This prevents an excessive concentration of stresses.For this reason, the stress lines in the present semiconductor component 1 are shown in Figure 3 as less dense than in the known semiconductor component 16. Cracks and fractures in the housing 5 can thus be reduced or prevented.

[0055] 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 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 essentially explained below.

[0056] All three embodiments of the semiconductor components 1 shown in Fig. 4 have in common that they have solder control structures 9 with anchors 17 embedded in the housing 5. By way of example, each solder control structure 9 has two anchors 17. It may also be sufficient if each solder control structure 9 has only one anchor 9. Alternatively, more than two anchors 17 can be provided per solder control structure 9. Likewise by way of example, the anchors 17 of the solder control structures 9 of a respective semiconductor component 1 are designed differently. In general, however, the anchors 17 of a semiconductor component 1 can also be designed identically for all solder control structures 9. Also not all solder control structures 9 of a semiconductor component 1 have to have an anchor 17. However, the anchors 17 offer the advantage that the solder control structures 9 are better connected to the housing 5.This may be necessary because mechanical stability of the solder control structures 9 may be reduced due to separation from the contact pads 7, 8.

[0057] Fig. 4 shows on the left-hand side a semiconductor component 1 with solder control structures 9, the exemplary anchors 17 of which are bar-shaped and each protrude from the solder control structures 9 in a direction parallel to the mounting surface 6. First anchors 17 of a first solder control structure 9 are arranged tangentially at corners of the first solder control structure 9 and second anchors 17 of a second solder control structure 9 are arranged protruding from corners of the second solder control structure 9 and running essentially parallel to side walls 10 of the housing 5. The first anchors 17 are therefore arranged transversely to the second anchors 17. In addition, the second anchors 17 are longer than the first anchors 17, but they can also be of the same length and oriented, for example.

[0058] The semiconductor component 1 shown in the center of Fig. 4 has, by way of example, a third solder control structure 9 with two third anchors 17 and a fourth solder control structure 9 with a fourth anchor 17. The third anchors 17 are essentially designed like the second anchors 17 of the second solder control structure 9 of the semiconductor component 1 shown on the left-hand side, but are significantly shorter.

[0059] The fourth anchoring 17 of the fourth soldering control structure 9 is bar-shaped and arranged parallel to a side wall 10 of the housing 5. However, the fourth anchoring 17 does not extend directly from a corner or side surface of the fourth soldering control structure 9. Instead, the fourth soldering 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 soldering control structure 9 and is arranged perpendicular to the side surface of the fourth soldering 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-shape and embedded or anchored in the housing material, whereby particularly reliable anchoring of the fourth soldering control structure 9 in the housing 5 is ensured. Fig.4 shows on the right-hand side an exemplary semiconductor component 1 with a fifth solder control structure 9 with two fifth anchors 17 and a sixth solder control structure 9 with two sixth anchors 17. The sixth anchors 17 are designed essentially like the fourth anchor 17 of the fourth solder control structure 9 of the semiconductor component 1 shown in the middle, however they do not extend from a side surface of the sixth solder control structure 9, but rather from a corner of the sixth solder control structure 9 in each case, such that the anchors 17 are arranged transversely to the side surfaces 10 of the housing. The fifth anchors 17 are designed similarly to the second anchors 17, but the fifth anchors 17 are additionally curved and have a bead at their ends. All anchors 17 can also extend in a direction perpendicular to the mounting surface 6 of the housing 5.

[0060] In the following, method steps of a method for producing a semiconductor component 1 are explained. Figs. 5 to 8 each show a lead frame assembly 19, 20, 21, 22 for producing a plurality of semiconductor components 1 in a transparent bottom view. In this case, a housing body assembly or the housings 5 ​​are each completely transparent. The semiconductor chips are not shown in Figs. 5 to 8 for the sake of clarity. Previously used reference numerals are retained below.

[0061] Figs. 5 to 8 each show a state after performing a first method step, during which a leadframe assembly 19, 20, 21, 22 was embedded in a housing body assembly. The leadframe assembly 19, 20, 21, 22 can be embedded, for example, by means of a molding process, such as FAM.

[0062] 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 has 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 and 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 structure elements 23 have recesses 24.

[0063] In a second method step, semiconductor chips are arranged on the first leadframe assembly 19. In each case, one semiconductor chip is electrically connected to a first and second contact pad 7, 8. The semiconductor chips can be arranged on the first leadframe assembly 19, for example, after the first leadframe assembly 19 has been embedded in the housing body assembly, for example by arranging the semiconductor chips in the cavities 12 of the housings 5. However, the semiconductor chips can also be arranged on the first leadframe assembly 19 before the first leadframe assembly 19 is embedded in the housing body assembly.

[0064] In a third method step, the first leadframe assembly 19 and the housing body assembly are separated into separate semiconductor components 1. The separation can be carried out, for example, by sawing. In Figs. 5 to 8, separation planes 25 are shown, which extend perpendicular to the conductor track plane or perpendicular to the mounting surfaces 6 of the housing 5 to be produced. The separation takes place along the separation planes 25.

[0065] One semiconductor chip each, 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 created by singulating the housing body composite. The singulation takes place in regions of the connecting webs and the recesses 24 of the solder control structure elements 23, whereby the solder control structure elements 23 are divided into solder control structures 9 with recesses 11 accessible on mounting surfaces 6 and each of at least one side wall 10 of the housing 5 for receiving a solder material, and the contact pads 7, 8 and the solder control structures 9 are separated from one another.

[0066] In the first lead frame 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 second connecting webs 26, 27 are arranged parallel to one another. In each case, a first contact pad 7 is connected to a respective second contact pad 8 via third connecting webs 28. For example, two third connecting webs 28 each 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.

[0067] One solder control structure element 23 is arranged between each two adjacent first contact pads 7. The solder control structure 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. At the crossing points, the fourth connecting webs 29 are firmly connected to the first and second connecting webs 26, 27.

[0068] The separation of the first lead frame assembly 19 and the housing body assembly takes place in the area of ​​the solder control structure elements 23 along the fourth connecting webs 29 and in the area of ​​the third connecting webs 28 perpendicular to the third connecting webs 28. The separation planes 25 therefore run in these areas. The fourth connecting webs 29 are completely removed in the process. Because the fourth connecting webs 29 connect the solder control structure elements 23 to one another, the solder control structure elements 23 are halved. For each semiconductor component 1, two opposing solder control structures 9 are formed with recesses 11 accessible on the mounting surfaces 6 and side walls 10 of the housing 5, since in each case one solder control structure element 23 is arranged between two adjacent first contact pads 7.

[0069] The first, second and third connecting webs 26, 27, 28 can be exposed and accessible on the side walls 10 of the housing 5 after singulation. By way of example, Fig. 5 shows that the first lead frame assembly 19 has a smaller thickness measured perpendicular to the mounting surface 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, for example, a smaller thickness in edge regions than in their other regions. Because the connecting webs have a smaller thickness, singulation can be simplified.

[0070] Fig. 6 schematically shows an exemplary second leadframe assembly 20, which is suitable for producing semiconductor components 1 with a total of four solder control structures 9, each of which is arranged in housing corners. The second leadframe assembly 20 has similarities to the first leadframe assembly 19. The essential differences between the second leadframe assembly 20 and the first leadframe assembly 19 are explained below. The reference symbols are retained for similar or identical elements.

[0071] 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, however, are not connected to one another via second connecting webs 27. The second connecting webs 27 are therefore omitted in the second leadframe assembly 20. In each case, a first contact pad 7 is connected to a respective second contact pad 8 via third connecting webs 28. For example, two third connecting webs 28 connect a respective 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.

[0072] 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. In the second lead frame assembly 20, as in the first lead frame assembly 19, the solder control structure 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 connecting webs 26 and cross the first connecting webs 26. In addition, the solder control structures 23 are connected to one another via fifth connecting webs 30. The fifth connecting webs 30 are arranged perpendicular to the third and fourth connecting webs 28, 29.

[0073] The singulation of the second leadframe assembly 19 and 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 perpendicular to the third connecting webs 28. The fourth and fifth connecting webs 29, 30 are also completely removed in the process. Because the fourth and fifth connecting webs 29, 30 connect the solder control structure elements 23 to one another, the solder control structure elements 23 are quartered during singulation. Four solder control structures 9 are formed for each semiconductor component 1, which are each arranged in a housing corner, since the fourth and fifth connecting webs 29, 30 intersect in the region of the solder control structure elements 23. In other words, the singulation 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, which is suitable for producing further semiconductor components 1. The third leadframe assembly 21 has similarities to the first leadframe assembly 19. The following essentially explains the differences between the third leadframe assembly 21 and the first leadframe assembly 19. The reference symbols are retained for similar or identical elements.

[0074] The third leadframe assembly 21, like the first leadframe assembly 19, has the first, second and third connecting webs 26, 27, 28. Likewise, a solder control structure element 23 is arranged between each two adjacent first contact pads 7. The fourth and fifth connecting webs 29, 30 are omitted in the third leadframe assembly 21. The solder control structure elements 23 are each connected to a first contact pad 7 via sixth connecting webs 31. The sixth connecting webs 31 are arranged parallel to the first and second connecting webs 26, 27. A first contact pad 7 is each connected to 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 singulation takes place in the region of the solder control structure elements 23 and in regions of the first, second, and seventh connecting webs 26, 27, 32 perpendicular to the first and second connecting webs 26, 27, 32, and in regions of the third connecting webs 28 perpendicular to the third connecting webs 28. In this case, no connecting web is completely removed by the singulation. As a result, there is less metal in the region of the singulation planes 25 in the third leadframe assembly 21, which simplifies the singulation.

[0075] 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, after the third lead frame assembly 21 has been separated, a solder control structure 9 and a further solder control structure 33 remain with a further recess 34 accessible at least on the mounting surface 6 of the housing 5 for receiving a solder material in the semiconductor component 1.

[0076] 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 each formed by a common section of the lead frame 2 even after the third lead frame assembly 21 has been separated. The further recesses 34 of the further solder control structures 33 are accessible not only on the mounting surface 6 but also on at least one side wall 10 of the housing 5. Alternatively, the further solder control structure 33 can only be accessible 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.

[0077] Fig. 8 schematically shows an exemplary fourth leadframe assembly 22, which is suitable for producing further semiconductor components 1. The fourth leadframe assembly 22 has similarities to the third leadframe assembly 21. The following essentially explains the differences between the fourth leadframe assembly 22 and the third leadframe assembly 21. The reference symbols are retained for similar or identical elements.

[0078] In contrast to the third lead frame assembly 21, the solder control structure elements 23 in the fourth lead frame assembly 22 are not each connected to a first contact pad 7 via sixth connecting webs 31. Rather, the sixth connecting webs 31 are omitted in the fourth lead frame assembly 22. Instead, 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. Furthermore, 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, in the fourth lead frame assembly 22 too, less material of the fourth lead frame assembly 22 is located in the region of the separation levels 25.

[0079] The invention has been illustrated and described in more detail using preferred embodiments. However, the invention is not limited to the disclosed examples. Rather, other variations may be derived therefrom by those skilled in the art without departing from the scope of the invention.

[0080] LIST OF REFERENCE SYMBOLS Semiconductor component Lead frame Top side of the lead frame Bottom side of the lead frame Housing Mounting surface of the housing First contact pad Second contact pad Solder control structure Side wall of the housing Recess of the solder control structure Cavity Semiconductor chip Printed circuit board Orientation mark Semiconductor component according to the prior art Anchoring Connecting element for anchoring First lead frame assembly Second lead frame assembly Third lead frame assembly Fourth lead frame assembly Solder control structure elements Recesses of the solder control structure elements Separation levels First connecting webs Second connecting webs Third connecting webs Fourth connecting webs Fifth connecting webs Sixth connecting webs Seventh connecting webs Further solder control structure Further recess of the further solder control structure Eighth connecting webs

Claims

PATENT CLAIMS 1. Semiconductor component (1) comprising a housing (5) with a mounting surface (6), a lead frame (2) embedded in the housing (5) with 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) accessible on 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 unconnected sections of the lead frame (2).

2. Semiconductor component (1) according to claim 1, wherein the lead frame (2) has at least two solder control structures (9) with recesses (11) accessible on 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 unconnected sections of the lead frame (2).

3. Semiconductor component (1) according to claim 2, wherein the solder control structures (9) are arranged on opposite side walls (10) of the housing (5) and / or in the region of corners of the housing (5).

4. Semiconductor component (1) according to one of the preceding claims, wherein the solder control structure (9) has at least one anchor (17) embedded in the housing (5).

5. Semiconductor component (1) according to claim 4, wherein the anchoring (17) is bar-shaped and extends from the solder control structure (9) in a direction parallel to the mounting surface (6).

6. Semiconductor component (1) according to claim 4 or 5, wherein the solder control structure (9) is a (17) connected connecting element (18).

7. 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) accessible at least on the mounting surface (6) of the housing (5) for receiving a solder material.

8. 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 at least partially not covered by a housing material and are exposed at a bottom of the cavity (12) arranged parallel to the mounting surface (6), wherein the semiconductor chip (13) is arranged at the bottom of the cavity (12).

9. Method for producing a semiconductor component (1) with the following method steps: - Embedding a leadframe assembly (19, 20, 21, 22) in a housing 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 structural elements (23), wherein the first and second contact pads (7, 8) and the solder control structural 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 structural elements (23) have recesses (24), - Arranging semiconductor chips (13) on the lead frame assembly (19, 20, 21, 22), wherein in each case a semiconductor chip (13) is electrically connected to a first and second contact pad (7, 8), - separating the leadframe assembly (19, 20, 21, 22) and 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) created by separating the housing body assembly, wherein the separating takes place in regions of the connecting webs (26, 27, 28, 29, 30, 31, 32, 35) and the recesses (24) of the solder control structure elements (23), whereby the solder control structure elements (23) are separated into solder control structures (9) with mounting surfaces (6) and in each case at least one Side wall (10) of the housing (5) accessible recesses (11) for receiving a solder material are divided and the contact pads (7,8) and the solder control structures (9) are separated from each other., 10. The method according to claim 9, wherein prior to embedding the leadframe assembly (19, 20, 21, 22) in the housing body assembly, a sacrificial material is arranged in the recesses (24) of the solder control structure elements (23).

11. The 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 second connecting webs (26, 27) are arranged parallel to one another, wherein in each case a first contact pad (7) is connected to 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, 8), wherein the solder control structure elements (23) are each 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 singulation in the region of the solder control structure elements (23) takes place along the fourth connecting webs (29) and in the region of the third connecting webs (28) perpendicular to the third connecting webs (28).

12. The 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 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 each 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 (29,30) and in the region of the third connecting webs (28) perpendicular to the third connecting webs (28).

13. 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 second connecting webs (26, 27) are arranged parallel to one another, wherein in each case a first contact pad (7) is connected to a respective 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 structure 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 singulation in the region of the solder control structure elements (23) and in regions of the first, second and seventh connecting webs (26, 27, 32) is perpendicular to the first and second connecting webs (26,27) and in areas of the third connecting webs (28) perpendicular to the third connecting webs (28).

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