ELECTRONIC DEVICE AND METHOD FOR MANUFACTURING AN ELECTRONIC DEVICE

Abstract

Electronic device (100), comprising - a housing body (2) with a cavity (20) in which an electronic semiconductor chip (1) is mounted, and - a cover element (3) which is filled into the cavity (20) and covers the semiconductor chip (1), wherein - the cavity (20) has a side wall (22) which faces the semiconductor chip (1) and surrounds the semiconductor chip (1) in a lateral direction, - the cover element (3) is in direct mechanical contact with the side wall (22) in at least one adhesion area and adheres directly to the housing body (2) in at least one adhesion area, - the housing body (2) has at least one anchoring structure (4) which is designed and configured to reduce the tendency of the cover element (3) to delaminate from the housing body (2) in at least one adhesion area, and - the anchoring structure (4) has a roughening (40) and at least one column element (42) formed on a floor surface (23) of the cavity and / or a plurality of island-shaped elevations and / or sack-like depressions (45) arranged in a pearl-like fashion in a lateral direction.

Description

[0001] An electronic device and a method for manufacturing an electronic device are provided. The electronic device comprises, in particular, an electronic semiconductor chip in a housing body. The housing body can form at least part of a so-called package.

[0002] Typical packages, for example, comprise a plastic housing with a cavity in which at least one semiconductor chip is mounted and encapsulated, for example, with a potting material. The surfaces of the cavity are usually flat and smooth, for example, to achieve the highest possible reflectivity, and correspond, for example, to the milled or ground surfaces of the mold used to manufacture the housing, so that the potting compound rests flat on these surfaces.

[0003] Due to the finite mutual adhesion of the adjoining materials and their different coefficients of thermal expansion (CTE), which can lead to (interfacial) stresses building up during temperature changes and tending to relax, there is a risk of delamination of the encapsulation from the cavity wall and / or material cracks. Such delamination and cracks represent a quality problem and can, for example, lead to field failures and thus result in high costs.

[0004] To reduce the risk of delamination, it is known, for example, to perform a plasma treatment before filling the encapsulant into the cavity, which can increase adhesion at the interfaces to the encapsulant. However, such plasma treatments entail increased time and cost.

[0005] The document US 2012 / 0 018 772 A1 describes a light-emitting component with a housing which has integrally formed elevations in the side wall of a recess which is filled with a potting compound.

[0006] The document JP 2010 - 129 655 A describes an LED component with a housing having a recess which is filled with a potting compound and on the side wall of which a spiral-shaped groove is formed which is intended to prevent the potting compound from detaching.

[0007] The document US 2012 / 0 153 334 A1 describes an LED package with a housing having a recess which is filled with a potting compound and on whose side surface vertically extending elevations are formed.

[0008] The publication US 2009 / 0 134 408 A1 describes an LED package comprising a housing body with a recess in which LED chips are mounted. The recess has annular protrusions with grooves in between, which are intended to prevent delamination of a protective resin in the recess.

[0009] At least one object of certain embodiments is to provide an electronic device. At least another object of certain embodiments is to provide a method for manufacturing an electronic device.

[0010] These objects are achieved by a subject matter and by methods according to the independent patent claims. Advantageous embodiments and further developments of the subject matter and method are characterized in the dependent claims and will further become apparent from the following description and the drawings.

[0011] According to at least one embodiment, an electronic device comprises a housing body with a cavity in which an electronic semiconductor chip is mounted.

[0012] According to at least one further embodiment, in a method for producing an electronic device, a housing body is formed and an electronic semiconductor chip is mounted in the housing body.

[0013] The following description refers equally to the electronic device and the method for manufacturing the electronic device.

[0014] According to a further embodiment, the electronic semiconductor chip, which may also be referred to simply as a semiconductor chip below, is an optoelectronic semiconductor chip. In particular, the semiconductor chip may be a light-emitting semiconductor chip, such as a light-emitting diode. The electronic device is then accordingly a light-emitting device. Alternatively or additionally, the electronic device may also have a light-absorbing semiconductor chip, such as a photodiode chip, as the electronic semiconductor chip. In this case, the electronic device may be a light-absorbing device. Furthermore, it is also possible for the electronic semiconductor chip to have no optoelectronic properties and to be designed as a purely electronic semiconductor chip.Although the following describes an electronic device with exactly one electronic semiconductor chip, the electronic device may also comprise a plurality of identical or different semiconductor chips that may be arranged and mounted in the cavity. The following description therefore also applies accordingly to a plurality of semiconductor chips mounted in the cavity.

[0015] The electronic semiconductor chip can, in particular, be mounted and electrically connected on a mounting surface of the housing body. The arrangement direction of the semiconductor chip on the mounting surface, which can be part of a bottom surface of the housing body, is referred to here and below as the vertical direction. Directions perpendicular to the vertical direction are referred to here and below as lateral directions. Terms such as "top," "bottom," "top side," and "bottom side" refer to the vertical direction unless otherwise stated. Terms such as "next to" refer to a lateral direction unless otherwise stated.

[0016] The housing body can, in particular, form part of a so-called package and particularly preferably comprise a plastic material that forms the cavity. For example, the housing body can be part of a so-called QFN package (QFN: "quad flat no leads") or a so-called premold package, in which leadframe parts for electrically contacting the semiconductor chip are provided in a plastic housing body. Other housing designs are also possible.

[0017] Particularly preferably, at least the part of the housing body that forms the cavity can be produced by means of a molding process, for example by injection molding, casting, or compression molding. A molding tool is used for the molding process. The molding tool has, for example, a mold chamber, which, optionally with elements to be formed, such as leadframe parts, inserted into the mold chamber, forms a negative mold of the housing body to be molded. For example, injection molding or transfer molding is used as the molding process. The material to be molded, in the case of the housing body described here a plastic material, is inserted into a chamber of a molding tool. From there, the material to be molded is pressed into the mold chamber under the action of heat and / or pressure. Furthermore, the molding process can also be, for example, compression molding.The material to be molded, in the case of the housing body described here, a plastic material, is introduced into the molding chamber of a molding tool. The material to be molded is shaped into the desired form by applying heat and / or pressure. The molding process is particularly preferably carried out in a composite process. This means that a coherent composite of a plurality of housing bodies is produced by the molding process, which can be separated in a subsequent process step by cutting, for example, sawing, abrasive cutting, or laser cutting.

[0018] The plastic material for the housing body can, for example, comprise or be made of a thermoplastic or a thermoset, depending on the molding process and the application of the electronic device. For example, the plastic material can comprise siloxanes, epoxies, acrylates, methyl methacrylates, imides, carbonates, olefins, styrenes, urethanes, or derivatives thereof in the form of monomers, oligomers, or polymers, as well as mixtures, copolymers, or compounds thereof. For example, the plastic material can comprise or be made of an epoxy resin, polyphthalamide (PPA), polymethyl methacrylate (PMMA), polystyrene, polycarbonate (PC), polyacrylate, polyurethane, or a silicone resin such as polysiloxane, or mixtures thereof.

[0019] The electronic device can further comprise a cover element that is filled into the cavity and covers the semiconductor chip. Particularly preferably, the semiconductor chip can be encased by the cover element. This can mean, in particular, that the semiconductor chip is reshaped by the cover element or that the cover element is molded onto the sides of the semiconductor chip that were free before the cover element was applied. In particular, the cover element can be a so-called encapsulation. Here and below, encapsulation refers to a material that is filled into the cavity in a viscous, i.e., in particular, in a liquid or partially liquid form, and that is cured simultaneously or subsequently. In particular, a cover material can therefore be filled into the cavity to form the cover element.After curing, the encapsulation, i.e., the cover element, can exhibit elastic or thermosetting properties. One of the previously described molding processes can be used to fill the cover material into the cavity. Furthermore, the cover material can also be poured into the cavity, for example. For example, the cover material can be a silicone resin or another material previously mentioned in connection with the housing body.

[0020] According to a further embodiment, the cavity has a sidewall that faces the semiconductor chip and that surrounds the cavity and thus the semiconductor chip in a lateral direction. The sidewall can run parallel to the vertical direction and thus be a perpendicular or substantially perpendicular sidewall. Particularly preferably, the sidewall is inclined to the vertical direction and thus is an inclined sidewall. An inclined sidewall can, for example, be designed as a reflector, which, in the case of a light-emitting device with a light-emitting semiconductor chip, can direct light that is emitted by the semiconductor chip in a lateral direction onto the sidewall during operation in the direction of the vertical direction and thus out of the cavity.

[0021] According to a further embodiment, the cover element is in direct mechanical contact with the side wall in at least one adhesion region. In at least one adhesion region, the cover element can adhere directly to the housing body and thus directly to the side wall. In other words, the at least one adhesion region is a region in which an adhesion force exists between the housing body and the cover element at the interface.

[0022] Particularly preferably, the at least one adhesion region comprises at least a portion of the sidewall of the cavity or else the entire sidewall. In other words, the cover element adheres directly to a portion of the sidewall of the cavity or to the entire sidewall in at least one adhesion region. Thus, the at least one adhesion region can preferably completely surround the semiconductor chip in the lateral direction.

[0023] According to a further embodiment, the housing body has at least one anchoring structure that is provided and configured to reduce a tendency of the cover element to delaminate from the housing body in at least one adhesion region. In other words, the tendency for the cover element to detach at least from the side wall in the adhesion region can be reduced by the anchoring structure compared to a comparable housing body without the anchoring structure. As described below, the anchoring structure can have microscopic or macroscopic anchoring elements and, in particular, can be provided and configured to improve the mechanical anchoring of the cover element by creating anchoring elements for stress absorption and / or to improve the adhesion of the cover element in at least one adhesion region to the housing body by enlarging the effective interface.Particularly preferably, the anchoring structure can form a replacement for other additional and often expensive processes such as a plasma treatment of the housing body.

[0024] The features and embodiments of the anchoring structure described below can be present alone or in combination. In particular, the anchoring structure can comprise several identical or different anchoring elements according to the following description.

[0025] According to a further embodiment, the anchoring structure is formed in at least one adhesion region. In particular, the anchoring structure can be formed in or on the side surface of the cavity. Particularly preferably, the anchoring structure can have at least one recess and / or elevation in the side wall of the cavity.

[0026] For example, the anchoring structure can have a roughening, which can be formed by a plurality of regularly or irregularly arranged elevations and / or depressions. The roughening and thus the elevations and / or depressions can particularly preferably have structural sizes of less than or equal to 100 µm, or less than or equal to 50 µm, or less than or equal to 20 µm, or preferably less than or equal to 15 µm. Furthermore, the roughening and thus the elevations and / or depressions can have structural sizes of greater than or equal to 1 µm, or greater than or equal to 2 µm, or greater than or equal to 5 µm.

[0027] For example, the housing body, which as described above can comprise or be formed from a plastic body, can have the roughening at least on all surfaces of the plastic body that are in direct mechanical contact with the cover element. In other words, the entire adhesion region between the housing body and the cover element can have the roughening. In addition, other surfaces of the housing body can also have a roughening. For example, such a roughening, preferably over a large area, can be produced by an etching process or by laser structuring. Furthermore, it can also be possible for a foil-assisted molding process (FAM) to be used to form the housing body, and for the roughening to be formed by the film. This can be achieved, for example, by a film that has a surface structure corresponding to the roughening.In addition, it may also be possible for the molding tool used to form the housing body to have, at least in some areas, a surface structure corresponding to the roughening and thus a negative form of the anchoring structure.

[0028] According to a further embodiment, the anchoring structure has anchoring elements, particularly preferably in the form of a roughened portion, which are arranged in the vertical direction on the sidewall of the cavity above the semiconductor chip. In particular, the sidewall can have an upper region that projects above the semiconductor chip in the vertical direction, wherein the anchoring structure is only arranged in the upper region as viewed from the semiconductor chip in the vertical direction. If a plane is thus imagined that is perpendicular to the vertical direction and is arranged on the upper side of the semiconductor chip that delimits the semiconductor chip in the vertical direction, the upper region and thus the anchoring structure in this case are only arranged above this plane. Simply put, the anchoring structure is therefore arranged higher than the upper edge of the semiconductor chip.Particularly preferably, the anchoring structure is arranged only in an upper part of the upper region, viewed vertically from the semiconductor chip, wherein the upper part, from an upper edge of the sidewall, occupies a proportion of less than or equal to 80%, less than or equal to 66%, or less than or equal to 50% of the upper region. In the case of a roughening with such properties, the anchoring structure can preferably be produced by means of the molding process with which the housing body is formed. In particular, a negative mold of the anchoring structure can be provided in the molding tool for the roughening.

[0029] While the roughening described above forms microscopic anchoring elements of the anchoring structure, the anchoring structure can alternatively or additionally also comprise macroscopic anchoring elements such as those described below. The macroscopic anchoring elements can preferably form undercuts at least in some lateral directions, which allow for improved anchoring of the cover element in the cavity.

[0030] For example, the anchoring structure can have at least one web running along the sidewall. In other words, the sidewall contains a raised portion that is web-shaped, i.e., preferably has a greater extent in one direction than in the two directions perpendicular thereto. The at least one web can preferably run in a vertical direction. For example, the web can run from a bottom surface of the cavity to an upper edge of the cavity. Particularly preferably, the anchoring structure can have a plurality of webs running in a vertical direction, which can be arranged substantially uniformly distributed in the lateral direction around the semiconductor chip.It may also be possible for the cavity to have a cross-section which has a square or rectangular basic shape, for example with rounded corners, and for such webs running in the vertical direction to be arranged at least in the area of ​​the corners.

[0031] According to a further embodiment, the anchoring structure has at least one anchoring element that is arranged at a distance from the side wall and in particular from the adhesion region. In particular, the anchoring structure can have at least one column element formed on a bottom surface of the cavity. The column element can particularly preferably have a square or round cross-section and extend vertically upwards from the bottom surface of the cavity. For example, such a column element can have a height that is at the same height or lower in the vertical direction than an edge delimiting the cavity at the top, so that the column element does not protrude from the cover element after the cover element has been applied and is particularly preferably covered by it.Particularly preferably, the anchoring structure can comprise a plurality of such column elements, which can be arranged symmetrically in the lateral direction next to or around the semiconductor chip.

[0032] Anchoring elements such as the described vertically extending webs and column elements can preferably be manufactured by means of the molding process for forming the housing body simultaneously with the formation of the housing body. For this purpose, the mold used can have a negative mold of the anchoring structure. To facilitate demolding, the web(s) or column element(s) of the anchoring structure can have a width that decreases upwards in the vertical direction, measured in the lateral direction. In other words, the vertical web(s) or column elements can be designed to taper upwards and have a truncated pyramid or truncated cone shape.

[0033] According to a further embodiment, the anchoring structure has at least one web running in the lateral direction on the side wall. In particular, the web can be formed on the side wall so as to extend circumferentially around the semiconductor chip and thus form an elevation surrounding the semiconductor chip. Furthermore, the anchoring structure can have at least one groove running in the lateral direction in the side wall. In particular, the groove can be formed on the side wall so as to extend circumferentially around the semiconductor chip and thus form a groove surrounding the semiconductor chip. Alternatively, a plurality of webs and / or grooves separated from one another in the laterally direction and running in the lateral direction on the side surface of the cavity can also be provided. For example, the anchoring structure can have a plurality of island-shaped elevations and / or blind-hole-like depressions arranged in the lateral direction like a string of pearls.Such anchoring elements can be manufactured, for example, using a suitable molding tool as described above or by laser structuring, or alternatively, they can be provided as prefabricated anchoring elements and applied to the housing body. In this case, the anchoring elements can be glued on, for example.

[0034] In the previously described embodiments and features of the anchoring structure, the covering material particularly preferably has a viscosity and the anchoring structure a structural size, wherein the structural size and the viscosity are adapted to one another in such a way that the anchoring structure is in complete direct contact with the finished covering element. In other words, the anchoring structure and the covering material are preferably adapted to one another in such a way that the covering material, and thus the covering element, completely transforms the anchoring structure. In particular, the covering material and the structural sizes can be adapted to one another in such a way that no bubbles or cavities are formed.

[0035] Further advantages, advantageous embodiments and further developments emerge from the exemplary embodiments described below in conjunction with the figures. Fig. 1 shows a schematic representation of a method for manufacturing an electronic device according to an embodiment, Fig. 2A to 2C show schematic representations of an electronic device according to another embodiment, Fig. 3A and Fig. 3B show schematic representations of an electronic device according to another embodiment, Fig. 4 shows a schematic representation of a method step of a method for producing an electronic device according to a further embodiment, Fig. 5A to 5C show schematic representations of an electronic device according to another embodiment, Fig. 6A to 6C show a schematic representation of a method step of a method for producing an electronic device according to a further embodiment as well as images of surfaces with roughening, Fig. 7A and Fig. 7B show schematic representations of an electronic device according to another embodiment, Fig. 8A and Fig. 8B show schematic representations of an electronic device according to another embodiment, Fig. 9A and Fig. 9B show schematic representations of an electronic device according to another embodiment and Fig. 10A and Fig. 10B show schematic representations of an electronic device according to another embodiment.

[0036] In the exemplary embodiments and figures, identical, similar, or similarly functioning elements may be provided with the same reference numerals. The illustrated elements and their relative sizes are not to be considered to scale; rather, individual elements, such as layers, components, structural elements, and regions, may be exaggerated for clarity and / or clarity.

[0037] In conjunction with the figures described below, the electronic device and methods for producing the same are explained according to several exemplary embodiments, wherein in the exemplary embodiments, purely by way of example and without limiting the invention, precisely one electronic semiconductor chip is arranged in a housing body, which is designed, for example, as a light-emitting semiconductor chip such as a light-emitting diode. Alternatively, however, it is also possible for the electronic semiconductor chip to be designed as a light-absorbing semiconductor chip such as a photodiode or as another optoelectronic semiconductor chip or even as a purely electronic semiconductor chip without an optoelectronic function. Furthermore, more than one semiconductor chip can also be present in the housing body.

[0038] In Fig. 1 shows a method for producing an electronic device, in which a housing body with a cavity is formed in a first method step 101. In particular, the housing body can be formed by means of a molding process using a suitable molding tool. Furthermore, an anchoring structure is formed in the housing body as part of the method, as indicated in a further method step 102. As explained below, the method steps 101 and 102 can also be carried out simultaneously as part of a common method step 110, as in Fig. 1. In a further method step 103, an electronic semiconductor chip is mounted in the cavity of the housing body. Furthermore, the semiconductor chip can also be electrically connected. In a further method step 104, a covering material is filled into the cavity to form a covering element. Further features of the method and the electronic device will become apparent from the exemplary embodiments shown in the other figures.

[0039] In the Fig. 2A to 2C show an embodiment of an electronic device 100 with an electronic semiconductor chip 1 in a three-dimensional plan view, a sectional view and a section of the sectional view. The following description refers equally to the Fig. 2A to 2C.

[0040] Purely by way of example, the electronic device 100 is designed as a so-called QFN package and comprises a housing body 2 with a cavity 20, which comprises a plastic material in which electrical and / or thermal connection elements 21, formed for example by a lead frame, are contained for electrically contacting the electronic semiconductor chip 1 arranged in the cavity, by means of which the electronic device 100 can also be soldered onto a carrier such as a printed circuit board. Purely by way of example, the electronic semiconductor chip 1 is mounted by means of an adhesive or solder on a lead frame piece provided as a heat sink, which forms a mounting surface of the housing body 2, and is electrically connected to further lead frame pieces by means of bonding wires. Instead of a QFN package, the electronic device 100 can also be designed in a different design.

[0041] The arrangement direction of the semiconductor chip 1 on the mounting surface is referred to here and below as the vertical direction. Directions perpendicular to the vertical direction are referred to as lateral directions.

[0042] The plastic material for the housing body 2 can, for example, comprise or be made of a thermoset such as a white or black epoxy, also referred to as EMC ("epoxy mold compound"), and / or PPA and / or PC. Alternatively, other plastic materials are also possible. The housing body 2 can be manufactured using a suitable molding process, for example, a method described above in the general section. In particular, the molding process can be used to produce a plurality of housing bodies 2 in the form of a composite, which can then be separated in a later process step.

[0043] In the cavity 20, a cover element 3 is arranged, which in Fig. 2A is omitted in order to show the elements arranged in the cavity. The cover element 3 is filled into the cavity 20 and covers the semiconductor chip 1. As in Fig. As can be seen in Figure 2B, the semiconductor chip 1 can particularly preferably be encased by the cover element 3. In particular, the cover element 3 can be a potting compound and is filled into the cavity 20 as a covering material in a liquid or partially liquid form and cured simultaneously or subsequently. For example, the cover element 3 can comprise or be a silicone resin. Alternatively, other plastic materials, as described above in the general section, are also possible.

[0044] The cavity 20 has a sidewall 22 that faces the semiconductor chip 1 and surrounds the cavity and thus the semiconductor chip 1 in the lateral direction. The sidewall 22 can be a vertical or substantially vertical sidewall or, as shown, an inclined sidewall. An inclined sidewall can, for example, be designed as a reflector, which, in the case of a light-emitting device with a light-emitting semiconductor chip, can direct light that is emitted by the semiconductor chip 1 in a lateral direction onto the sidewall 22 during operation in the vertical direction and thus out of the cavity. In this case, the cover element 3 can be transparent or translucent and, for example, also contain a phosphor that converts at least part of the light emitted by the semiconductor chip 1 during operation into light with a different wavelength.

[0045] As in the Fig. 2B and Fig. 2C, the cover element 3 is in direct mechanical contact with the housing body 2 at the side wall 22 and the bottom surface 23. Regions with such direct mechanical contact are referred to here and below as adhesion regions, since the cover element 3 can adhere directly to the housing body 2 in an adhesion region. The adhesion region can include at least a portion of the side wall 22 of the cavity 20 and, as shown, particularly preferably the entire or at least substantially the entire side surface 22. Furthermore, in the illustrated embodiment, the adhesion region also includes the bottom surface 23 of the housing body 2, which in the illustrated embodiment at least partially forms a so-called glue creep barrier (GCP), which prevents the adhesive or solder with which the semiconductor chip 1 is attached as described above from creeping to the regions in which the bond wires are electrically connected.Thus, in the embodiment shown, the adhesion region completely surrounds the semiconductor chip 1 in the lateral direction.

[0046] The electronic device according to the present and the following exemplary embodiments further comprises an anchoring structure that is provided and configured to reduce a tendency of the cover element to delaminate from the housing body in the adhesion region. As described in more detail below, the anchoring structure can comprise microscopic or macroscopic anchoring elements 40 and, in particular, can be provided and configured to improve the mechanical anchoring of the cover element 3 by creating anchoring elements for stress absorption and / or to improve the adhesion of the cover element 3 in at least one adhesion region to the housing body 2 by enlarging the effective interface.

[0047] In the embodiment shown, the anchoring structure 4 is formed as a roughening 40 on the entire adhesion area, i.e. on the entire side surface of the cavity and the bottom surface, as in Fig. 2C is indicated by the highlighted structure. The anchoring structure thus has, as anchoring elements, a plurality of regularly or irregularly arranged elevations and / or depressions, which can particularly preferably have structure sizes of less than or equal to 100 µm or less than or equal to 50 µm or less than or equal to 20 µm or preferably less than or equal to 15 µm and of greater than or equal to 1 µm or greater than or equal to 2 µm or greater than or equal to 5 µm. The roughening 40 can lead to an effective enlargement of the interface between the cover element 3 and the housing body 2 and thus to improved adhesion between them.

[0048] In the illustrated embodiment, a top side 24 of the housing body 2 and a portion of an outer surface 25 of the housing body 2 are also provided with the roughening 40. Only a portion of the outer surface 25, where the composite of housing bodies 2 was separated, for example by sawing, and the underside of the housing body 2 are free of the roughening 40.

[0049] In the Fig. 3A and Fig. 3B are according to the views in the Fig. 2A and Fig. 2C shows views of a further embodiment of the electronic device 100, in which the entire outer surfaces 25 are formed without roughening 40 due to the separation, for example by sawing.

[0050] For example, the anchoring structure 4 formed by a preferably large-area roughening 40 can be produced by an etching process after the molding process for forming the housing body 2 and in particular the housing body composite in order to achieve the previously described interface enlargement. Furthermore, it may also be possible that, as shown in a section in Fig. 4, a foil-assisted molding process (FAM) is used to form the housing body 2, and the roughening is formed by the foil 8. For this purpose, a foil 8 is inserted into a mold 9 for producing the housing body 2 during the molding process, which foil 8 has a surface structure corresponding to the roughening 40. Such a so-called mold foil has a surface facing the thermoplastic or thermoset material of the housing body 2 with a high surface roughness, which allows easy demolding and easy removal of the foil 8. For better clarity, the mold 9, the foil 8 and the formed housing body 2 are shown in Fig. 4 are shown spaced apart from one another. Furthermore, it may also be possible for the molding tool 9 used to form the housing body 2 to have, at least in partial areas, a surface structure corresponding to the roughening 40 and thus a negative form of the anchoring structure 4. This can be produced, for example, by selective etching or laser structuring.

[0051] In the Fig. 5A and Fig. 5B is shown in three-dimensional plan views as well as in Fig. 5C shows a further embodiment of the electronic device 100 in a section of a sectional view. In Fig. 5A is compared to the Fig. 5B, the cover element 3 is not shown in order to be able to show the elements arranged in the cavity 20. In comparison to the two previous embodiments, in this embodiment, the anchoring structure 4 has a roughening 40 that is not formed on the entire side wall 22 of the cavity 20 of the housing body 2. In particular, in the embodiment shown, the roughening 40 is formed only in a partial area of ​​the side wall 22 of the cavity 20 and not on any other surface of the housing body 2.

[0052] In particular, the side wall 22, as shown in Fig. 5C, an upper region 26 which projects above the semiconductor chip 1 in the vertical direction, wherein the anchoring structure 4 is arranged only in the upper region 26 as viewed in the vertical direction from the semiconductor chip 1. If a plane 29 is thus imagined which is perpendicular to the vertical direction and is arranged on the upper side of the semiconductor chip which delimits the semiconductor chip 1 in the vertical direction and whose position thus corresponds to the height of the semiconductor chip 1, the upper region 26 and thus the anchoring structure 4 are in this case arranged only above this plane 29. The anchoring structure 4 is thus arranged higher than the upper edge of the semiconductor chip 1.Particularly preferably, the anchoring structure 4 is arranged only in an upper part 27 of the upper region 26, viewed in the vertical direction from the semiconductor chip 1, wherein the upper part 27 occupies a proportion of less than or equal to 80% or less than or equal to 66% or less than or equal to 50% of the upper region 26 from an upper edge 28 of the side wall 22.

[0053] The anchoring structure 4 formed by the roughening 40 is designed in the form of a band laterally circumferentially around the semiconductor chip 1. The width of the band can, for example, be greater than or equal to 10 µm and less than or equal to 100 µm. Instead of the illustrated embodiment with one band, multiple bands with a circumferential roughening 40 can also be provided. Furthermore, an embodiment in the form of a periodically interrupted band, i.e., separate regions with the roughening 40, is also possible.

[0054] The anchoring structure 4 according to the embodiment of the Fig. 5A to 5C can be manufactured by means of the molding process with which the housing body 2 is formed. In particular, a negative mold 90 of the anchoring structure 4 can be provided in the mold 9 for the roughening 40, as in Fig. 6A. The negative mold 90 for the anchoring structure 4 can be introduced into the mold 9, for example, by means of laser structuring. Similar to the previous embodiments, at least the entire side wall 22 can also be provided with the roughening 40 in this way.

[0055] As in the previous exemplary embodiments, the roughening 40 can preferably have structural sizes of less than or equal to 100 µm or less than or equal to 50 µm or less than or equal to 20 µm or preferably less than or equal to 15 µm and of greater than or equal to 1 µm or greater than or equal to 2 µm or greater than or equal to 5 µm, wherein the roughening 40 is formed by correspondingly dimensioned elevations and / or depressions.

[0056] In Fig. Figure 6B is a micrograph of a section of a planar epoxy surface produced by such a mold, with a roughening 40 and a non-roughened area 49. The image shows a section with a side length of approximately 0.5 mm. Fig. Figure 6C shows further corresponding images as well as height profiles with roughenings of different structure sizes.

[0057] In addition or alternatively to a roughening 40, the anchoring structure 4 can also have larger anchoring elements, which preferably form undercuts in suitable directions in order to achieve anchoring of the cover element 3.

[0058] In the Fig. 7A and Fig. 7B shows a three-dimensional plan view and a section thereof of an embodiment of the electronic device 100, in which the anchoring structure 4 has at least one web 41 running along the side wall 22. The cover element is shown in the Fig. 7A and Fig. 7B as well as partly not shown in the following figures.

[0059] In particular, the side wall 22 contains raised portions that are web-shaped and, in the illustrated embodiment, extend vertically. As shown, a web 41 can extend from the bottom surface 23 of the cavity 20 to the upper edge 28 of the cavity 20.

[0060] Particularly preferably, the anchoring structure 4 has a plurality of webs 41 extending in the vertical direction, which can be arranged substantially uniformly distributed in the lateral direction around the semiconductor chip 1. In particular, it can be advantageous if the cavity 20, as shown, has a cross-section that has a square or rectangular basic shape, for example with rounded corners, and the webs 41 extending in the vertical direction are arranged in the region of the corners. In particular, the webs 41 can be placed where high stresses, in particular lateral stresses, can occur in the cover element or at the interface between the cover element and the housing body 2.As shown, their position can be particularly preferably selected, for example on the GCB, so that they do not require any additional space and thus the component size, the so-called footprint, of the electronic device 100 does not have to be increased.

[0061] The webs 41 of the anchoring structure 4 are preferably manufactured in one piece with the remaining housing body 2 and thus by means of the molding process for forming the housing body 2. The mold used for this purpose has a negative mold of the anchoring structure 4. To facilitate demolding, the webs 41 can, as indicated, have a width that decreases upwards in the vertical direction, measured in the lateral direction. In other words, the vertical webs 41 can be conical toward the top and have a truncated pyramid shape, thus tapering toward the top.

[0062] In the Fig. 8A and Fig. 8B shows a further exemplary embodiment in which the anchoring structure 4 has anchoring elements that are arranged at a distance from the side wall 22 and in particular from the adhesion region. For this purpose, the anchoring structure 4 can have one or more column elements 42 formed on a bottom surface 23 of the cavity 20. The column element(s) 42 can particularly preferably have a square or round cross-section and extend vertically upwards from the bottom surface 23 of the cavity 20. For example, the column elements 42 can have a height that is at the same height or lower in the vertical direction than the upper edge 28 delimiting the cavity 20 at the top, so that the column elements 42 do not protrude from the cover element after the cover element has been applied and are particularly preferably covered by it.

[0063] Particularly preferably, the anchoring structure 4, as shown, can comprise a plurality of column elements 42, which are arranged symmetrically in the lateral direction next to or around the semiconductor chip 1. As already described for the webs 42, the column elements 42 can also have an upwardly tapered shape. Such column elements 42 defined by the molding tool within the cavity 20, for example, on the GCB, enable the cover element and the housing body 2 to engage with each other and thus ideal stress absorption, in particular stresses in the lateral direction.

[0064] In the Fig. 9A and Fig. 9B shows a further embodiment in which the anchoring structure 4 has a web 43 extending in the lateral direction on the side wall 22. In particular, the web 43 can be formed on the side wall 22 circumferentially around the semiconductor chip 1, as shown, and thus form a raised portion circumferentially around the semiconductor chip 1. As shown in the Fig. 10A and Fig. 10B, the anchoring structure 4 can also have at least one groove 44 running in the lateral direction in the side wall 22. In particular, the groove 44 can be formed on the side wall 22 circumferentially around the semiconductor chip 1 and thus form a groove 44 circumferentially around the semiconductor chip 1. Instead of a circumferential web 43 and / or a circumferential groove 44 or in addition to these, the anchoring structure 4 can have a plurality of island-shaped elevations arranged in the lateral direction like a string of pearls, for example in the form of knobs, and / or blind hole-like depressions 45. Such depressions 45 are additionally provided in the exemplary embodiment of the Fig. 10A and Fig.10B. Such anchoring elements can be produced, for example, by means of a suitable molding tool as described above or by laser structuring, or alternatively, they can be provided as prefabricated anchoring elements and applied to the housing body 2. For example, the anchoring elements can be glued in this case. Studs, webs, grooves, and / or blind holes that adhere well to the side wall, for example, applied by such so-called additive manufacturing, can be enclosed by the cover element, or the cover element can fill them, so that it is firmly anchored in the cavity 20. While a circumferential web 43 and a circumferential groove 44 can enable good anchoring, particularly in the vertical direction, blind-hole-like depressions and studs can also enable good anchoring in the lateral direction.

[0065] The features and exemplary embodiments described in conjunction with the figures can be combined with one another according to further exemplary embodiments, even if not all combinations are explicitly described. Furthermore, the exemplary embodiments described in conjunction with the figures can alternatively or additionally comprise further features according to the description in the general part. List of reference symbols 1 semiconductor chip 2 housing bodies 3 Cover element 4 Anchoring structure 8 Slide 9 mold tool 20 cavities 21 Connection element 22 side wall 23 floor area 24 Top 25 exterior area 26 upper area 27 upper part 28 top edge 29 Level 40 Roughening 41 jetty 42 Column element 43 Bridge 44 gutter 45 Deepening 90 negative form 100 electronic devices 101, 102, 103, 104, 110 Process step

Claims

[1] Electronic device (100) comprising - a housing body (2) with a cavity (20) in which an electronic semiconductor chip (1) is mounted, and - a cover element (3) which is filled into the cavity (20) and covers the semiconductor chip (1), wherein - the cavity (20) has a side wall (22) which faces the semiconductor chip (1) and which surrounds the semiconductor chip (1) in a lateral direction, - the cover element (3) is in direct mechanical contact with the side wall (22) in at least one adhesion area and adheres directly to the housing body (2) in at least one adhesion area, - the housing body (2) has at least one anchoring structure (4) which is provided and designed to reduce a tendency of the cover element (3) to delaminate from the housing body (2) in at least one adhesion region, and - the anchoring structure (4) has a roughening (40) and at least one column element (42) formed on a bottom surface (23) of the cavity and / or a plurality of island-shaped elevations and / or blind-hole-like depressions (45) arranged in the lateral direction in the manner of a string of pearls. [2] Electronic device (100) according to claim 1, wherein the at least one adhesion region completely surrounds the semiconductor chip (1) in the lateral direction. [3] Electronic device (100) according to one of the preceding claims, wherein the anchoring structure (4) surrounds the semiconductor chip (1) in the lateral direction. [4] Electronic device (100) according to one of the preceding claims, wherein the anchoring structure (4) has at least one recess and / or elevation in the side wall (22) of the cavity (20). [5] Electronic device (100) according to one of claims 1 to 4, wherein the housing body (2) comprises a plastic material and the roughening (40) is formed at least on all surfaces of the plastic material which are in direct mechanical contact with the cover element (3). [6] Electronic device (100) according to one of claims 1 to 4, wherein the side wall (22) has an upper region (26) which projects beyond the semiconductor chip (1) in the vertical direction, and the anchoring structure (4) is arranged only in an upper part (27) of the upper region (26) as seen from the semiconductor chip (1) in the vertical direction, wherein the upper part (27) occupies a proportion of less than or equal to 80% of the upper region (26) from an upper edge (28) of the side wall (22). [7] Electronic device (100) according to one of the preceding claims, wherein the anchoring structure (4) has at least one web (41) extending in the vertical direction on the side wall (22). [8] Electronic device (100) according to one of the preceding claims, wherein the anchoring structure (4) has at least one web (43) extending in the lateral direction on the side wall (22). [9] Electronic device (100) according to one of the preceding claims, wherein the anchoring structure (4) has at least one groove (44) extending in the lateral direction in the side wall (22). [10] A method of manufacturing an electronic device (100) according to any one of the preceding claims, wherein - the housing body (2) with the cavity (20) is formed by means of a molding process using a molding tool (9), - the anchoring structure (4) is produced by means of the molding process, wherein a film-assisted molding process with a film (8) is used and the anchoring structure (4) has a roughening (40) which is formed by the film (8), - the electronic semiconductor chip (1) is mounted in the cavity (20) and - a covering material is filled into the cavity (20) to form the covering element (3). [11] A method for manufacturing an electronic device (100) according to any one of claims 1 to 9, wherein - the housing body (2) with the cavity (20) is formed by means of a molding process using a molding tool (9), - the anchoring structure (4) is produced by means of an etching process or by laser structuring or the anchoring structure has one or more prefabricated anchoring elements which are attached to the housing body after the molding process, - the electronic semiconductor chip (1) is mounted in the cavity (20) and - a covering material is filled into the cavity (20) to form the covering element (3). [12] Method according to claim 10 or 11, wherein the covering material has a viscosity and the anchoring structure (4) has a structure size, wherein the structure size and the viscosity are adapted to one another such that the anchoring structure (4) is in direct contact completely with the finished covering element (3).

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