Housing and leadframe unit

Abstract

In at least one embodiment, the housing (2) is provided for an optoelectronic semiconductor chip (3) and comprises: – a first leadframe part (41) and a second leadframe part (41), – a housing body (5), which mechanically connects the first and the second leadframe parts (41) to one another, wherein – the first leadframe part (41) has a mounting region (45) for attaching the semiconductor chip (3) and / or for attaching an electrical connection means (6), and also an edge region (46) at a lateral edge of the housing (2), – the first leadframe part (41) has a trench (7) between the mounting region (45) and the edge region (46), and – the trench (7) is situated at an outer side (44) of the first leadframe part (41), and the outer side (44) is configured for mounting of the housing (2), and the mounting region (45) and the edge region (46) extend as far as the outer side (44).

Description

[0001] Description

[0002] HOUSING AND LEAD FRAME ASSEMBLY

[0003] A housing for an optoelectronic semiconductor chip and a lead frame unit therefor are specified.

[0004] One problem to be solved is to provide a housing that is resistant to thermal stress.

[0005] This object is achieved, inter alia, by a housing and a leadframe unit having the features of the independent patent claims. Preferred developments are the subject of the dependent claims.

[0006] According to at least one embodiment, the housing is provided for at least one optoelectronic semiconductor chip. The semiconductor chip or chips are, for example, light-emitting diode chips (LED chips for short), and / or laser diode chips (LD chips for short). Several different types of optoelectronic semiconductor chips can be combined with one another in the housing, for example, optoelectronic semiconductor chips for generating different light colors.

[0007] According to at least one embodiment, the housing comprises a first leadframe part and a second leadframe part. Additional leadframe parts may be present. The term leadframe part refers in particular to metallic bodies that are, for example, punched and / or etched and / or cut from a sheet metal. All leadframe parts are preferably made of the same base material, in particular a copper sheet or a copper foil. The leadframe parts can be provided with at least one metallic coating, which, however, is preferably significantly thinner than the base material.

[0008] According to at least one embodiment, the housing comprises a housing body. The housing body is made of at least one electrically insulating material and is based, for example, on a plastic. The housing body can be based on an epoxy or silicone. It is possible for the housing body to contain admixtures, such as particles or fibers, to adapt to thermal expansion or to improve mechanical stability. The housing body is preferably opaque.

[0009] According to at least one embodiment, the housing body mechanically connects the first and second leadframe parts and optionally further leadframe parts to one another. This means that without the housing body, the leadframe parts would not be mechanically stable relative to one another. For example, the housing body partially or completely covers side surfaces of the leadframe parts, at least within the housing body. In the lateral direction, the leadframe parts are only exposed to the housing body on outer side walls of the housing, for example.

[0010] According to at least one embodiment, the first leadframe part has a mounting region for attaching a semiconductor chip and / or for attaching an electrical connection means. The semiconductor chip is, in particular, the at least one optoelectronic semiconductor chip; however, the semiconductor chip can also be another type of semiconductor chip, for example a control chip for the optoelectronic semiconductor chip or a protection chip, for example for protection against damage caused by electrostatic discharges (ESD for short). In the mounting region, the first leadframe part preferably has its full thickness.

[0011] In the same way, the second ladder frame part or optional further ladder frame parts can also have a mounting area.

[0012] According to at least one embodiment, the first leadframe part has an edge region. The edge region is preferably located on a lateral edge of the housing. This means that the edge region can border the outer side walls of the housing. The edge region preferably also has the full thickness of the first leadframe part, in particular with the exception of a solder control point, which can be completely surrounded by a region of the edge region with full thickness in the direction towards the housing body. The solder control point is preferably accessible from the outer side walls.

[0013] The mounting area and the edge area can have the same full thickness.

[0014] According to at least one embodiment, the first leadframe part has a trench. The trench is located between the mounting region and the edge region. In other words, it is possible for the trench to define a subdivision between the mounting region and the edge region. The mounting region is then located on one long side of the trench, and the edge region is located on an opposite long side. In the region of the trench, the first leadframe part is thinner than in the mounting region and than in the edge region, leaving out any solder control point.

[0015] According to at least one embodiment, the trench is located on an outer side of the first leadframe part. The outer side is configured for mounting the housing. The outer side is in particular opposite an inner side which is provided for the at least one optoelectronic semiconductor chip. For example, the outer side is configured for surface mounting, SMT for short or Surface Mount Technology, of the housing. The trench can therefore be understood as a depression in the first leadframe part which runs from the outer side into the base material of the first leadframe part towards the inner side, but does not reach as far as the inner side. The trench is therefore not a hole through the first leadframe part.

[0016] According to at least one embodiment, the mounting area and the edge area extend to the outer side. This means that the mounting area and the edge area are subregions of the outer side.

[0017] In at least one embodiment, the housing is provided for an optoelectronic semiconductor chip and comprises

[0018] - a first lead frame part and a second lead frame part,

[0019] - a housing body which mechanically connects the first and second lead frame parts, wherein

[0020] - the first leadframe part has a mounting area for attaching the semiconductor chip and / or for attaching an electrical connection means and an edge area on a lateral edge of the housing,

[0021] - the first leadframe part has a trench between the mounting area and the edge area, and

[0022] - the trench is located on an outer side of the first leadframe part and the outer side is configured for mounting the housing and the mounting area and the edge area extend to the outer side.

[0023] In the housing described here, solder control structures, in particular, are mechanically decoupled from the mounting area. This reduces the risk of delamination of the housing body from the first leadframe part in the edge region.

[0024] The package can be a so-called Quad Flat No Leads component, or QFN component for short.

[0025] The AEG Q102 #3 standard stipulates that delamination of metal pads on which bond wires are attached is not permitted. This standard specifically applies to LED components containing an IC intended for the automotive sector.

[0026] With the concept described here for the leadframe parts, the forces and stresses in the housing can be reduced to such an extent that the surrounding plastic of the housing body adheres to the metal of the leadframe parts. Studies show that the plastic on the top side of etched solder control structures, i.e. at the edge area, flakes off particularly easily. One reason for this is probably that large leadframe parts transmit a strong leverage effect to the solder control structures. With the concept described here, the affected solder control structures are mechanically decoupled from the large assembly area, but remain thermally and electrically connected.

[0027] In the narrow connection between the mounting area and the edge region, the material thickness is preferably halved in a straight line, for example, by removing material from the underside of the component—that is, the trench is formed. Viewed in longitudinal section and from above, the trench is preferably in the area of ​​a cavity rather than in the area of ​​a plastic housing wall. The trench is thus located, in particular, beneath a cavity floor, close to the cavity wall.

[0028] The continuous reduction of material thickness in the trench area creates a kind of joint between the large assembly area and the edge area with the solder control structures. The trench should run in a straight line to achieve maximum effect. The material is removed from the outside so that the remaining metal connection is closer to the neutral zone of an imaginary bend line.

[0029] If conventional QFN components are stored at a temperature and humidity level, for example according to a Temperature and Humidity Storage (THS) test, for 168 hours at 60°C and 85% relative humidity, and then soldered onto an FR4 circuit board, for example according to a Resistance To Soldering Heat test (RTSH) test, then delaminations often spread over a large area between a cavity encapsulation material and the metal leadframe. According to the AEG Q102 #3 standard, all delaminations between the cavity encapsulation material and metal pads are excluded for such LED components with ICs if these pads are wirebond pads.

[0030] Delamination occurs primarily due to the so-called popcorn effect. This means that during temperature and humidity storage a film of moisture forms in the gaps between the leadframe parts and the housing body. During subsequent soldering according to RTSH, maximum temperature 260 °C, this moisture evaporates suddenly and takes up a much larger volume in the form of hot water vapor. Viewed in longitudinal cross-section, the explosively formed water vapor shoots out of the gaps and squeezes directly between the cavity encapsulation material and the leadframe. The cavity encapsulation material is, for example, a silicone or an epoxy. This leads to large-scale delamination between the cavity encapsulation material and metal surfaces.

[0031] This means that the damage mechanism described is primarily caused by the gaps between the housing body and the metal leadframe. Firstly, the adhesion between the housing body, which can be based on an epoxy or silicone potting material, for example, and the metal is relatively low, and secondly the metal leadframe is quite stiff. In addition, the difference in the thermal expansion coefficients between metal and housing body leads to strong bends in the panel assembly, which is why the panel assembly is usually pressed flat several times by machine. In the housing described here, several approaches are combined: a) In general, the idea is to switch from so-called pre-plating to post-plating. For this, the leadframe, specifically the copper leadframe, is first provided with the housing body and only then is it coated with a metallization such as NiPdAu.The opposite process is used for pre-plating. The package body generally adheres better to copper than to a metallization such as NiPdAu. b) The solder control structures can be omitted in the area of ​​the second leadframe parts. This anchors the second leadframe parts better in the package body and also makes them more flexible. This can reduce gaps in the areas on the second leadframe part. c) However, the trenches and the solder control structures, also known as Solder Control Structure or SCS for short, are present on the preferably larger first leadframe parts. The trenches thus create a predetermined kink in the leadframe to protect the SCS area from forces that cause delamination.

[0032] Since the housing body is mechanically more stable, particularly in the area of ​​full material thickness, i.e. outside of a cavity, than in the area of ​​a cavity, the housing plastic has a greater tendency to deform in the area of ​​the cavity if the panel is bent. The metal leadframe is similarly rigid and would essentially retain its shape without the trench. The trench allows the leadframe to buckle. This can prevent half-side delamination starting on the inside of the edge area. This means that one of the ideas behind the housing described here is to create an additional kink point in the form of the trench outside the area of ​​the SCS, where the leadframe can buckle, so that the bond to the housing body no longer has to break under load.

[0033] This kink is preferably located directly on or close to the cavity wall. It is preferable to create this kink within the large, first cavity. However, it may be useful to create a kink on both sides of the SCS regions, including on the second leadframe part.

[0034] The following effects can be achieved with the housing described here:

[0035] - The solder control structures (SCS) can be left in place and do not need to be removed to solve the delamination problem. In conjunction with other measures, such as post-plating and / or customized shape of the second leadframe parts, this is an efficient measure to reduce the risk of delamination between the package body and the metal at a significant location, especially to achieve compliance with the AEG Q102 #3 standard.

[0036] - Another effect is that such delaminations above the SCS represent undesirable entry paths on the inside for gases, for example HgS, which are preferably avoided in order to achieve higher corrosion resistance.

[0037] According to at least one embodiment, the trench extends continuously between the mounting area and the edge area. This means in particular that between the mounting area and the edge area, no point of the lead frame is thicker than in the area of ​​a valley floor of the

[0038] Ditch . The ditch preferably extends along a straight line .

[0039] According to at least one embodiment, the trench is interrupted by one or more transverse webs. In particular, there is exactly one transverse web or exactly two transverse webs. Such transverse webs allow the material flow of the housing body to be controlled during its manufacture.

[0040] According to at least one embodiment, the at least one transverse web is as thick as the mounting area and / or the edge area. In the area of ​​the transverse webs, the first leadframe part therefore preferably has the full thickness.

[0041] According to at least one embodiment, a width of the transverse web or the sum of the widths of all transverse webs along the trench taken together amounts to at most 40%, or at most 30%, or at most 20% of a total length of the trench including the at least one transverse web. This means that the transverse webs are relatively narrow relative to the total length.

[0042] According to at least one embodiment, the trench is partially or completely filled by the housing body. In particular, if two transverse webs are present, the trench can be free of the housing body.

[0043] According to at least one embodiment, the housing body forms a first cavity. In the first cavity, an inner side of the first leadframe part, which is configured, for example, for attaching the semiconductor chip, is free from the housing body. It is possible for the first cavity to be limited to the first leadframe part, as seen in a plan view of the inner side. In this case, a second cavity may be present, which exposes the inner side of the second leadframe part. Alternatively, the first cavity extends over the first and second leadframe parts.

[0044] According to at least one embodiment, the edge region is partially or completely covered by a cavity wall of the first cavity, as seen from the inside in a top view. This means that the first cavity does not extend to the edge region, but in particular only to the groove.

[0045] According to at least one embodiment, the trench is located partially or completely within the first cavity when viewed from the inside.

[0046] According to at least one embodiment, the trench borders the cavity wall of the first cavity when viewed from the inside in a plan view and towards the edge region. In particular, a boundary line of the cavity wall, in the direction from an outer side wall of the housing at the edge region towards the mounting region, and a longitudinal edge of the trench facing the edge region then lie congruently one above the other when viewed from the inside in a plan view. This applies, for example, with a tolerance of at most 20 μm or of at most 50 μm or of at most 0.1 mm, alternatively or additionally with a tolerance of at most 10% or of at most 25% or of at most 50% of a width of the trench.

[0047] According to at least one embodiment, the cavity wall of the first cavity and the trench overlap partially or completely, preferably only to a small part of, for example, at most 40% or at most 20% of a base area of ​​the trench, seen in plan view of the inside.

[0048] According to at least one embodiment, all ends of the trench, viewed from the inside, lie within the first cavity. In other words, the trench ends within the first cavity.

[0049] According to at least one embodiment, the edge region comprises one or more solder control points. It is possible for the at least one solder control point to be provided with a metal coating. In particular, such a metal coating of the solder control point is located on a surface of the solder control point that runs transversely to the outer side. This transverse surface can lie in the plane of the associated outer side wall of the housing or be set back from the outer side wall. This metal coating is preferably the same metal coating as on the outer side of the mounting region and of regions of the edge region that lie on the outer side.

[0050] This means that the metal coating is applied to the first lead frame part at least in the area of ​​the solder control point and preferably also in the area of ​​the mounting area.

[0051] According to at least one embodiment, the edge region comprises a plurality of solder control points. It is possible for each edge region to have exactly one solder control point, or for an edge region to comprise several or even all of the solder control points of the respective leadframe part. If multiple edge regions with at least one solder control point are present, these edge regions can all be designed identically or can also differ from one another.

[0052] According to at least one embodiment, at least two of the solder control points are separated from one another in the direction transverse to the trench by a slot through the first leadframe part. This means that the respective solder control points can be adjacent to one another and have the same design. In particular, in the direction parallel to the trench, there is then no continuous material connection between these solder control points within the first leadframe part due to the slot.

[0053] According to at least one embodiment, the slot partially or completely separates the trench. This means that, due to the slot, no material of the first leadframe part is present at least in places in the direction parallel to the trench and in the region of the trench. It is possible for the trench to be divided into two partial trenches by the slot.

[0054] According to at least one embodiment, the slot widens in places in the direction away from the associated solder control points and, in particular, in the direction toward the trench. It is possible for the slot to remain the same width in a first plane and widen only in a second plane. The second plane is, for example, the half-etched side of the first leadframe part, into which the trench is also formed.

[0055] According to at least one embodiment, the trench is semicircular or polygonal, such as square, in places or along the entire longitudinal axis, viewed in cross section, in particular viewed perpendicular to a longitudinal axis of the trench.

[0056] For example, quadrangular means that the trench has a square or trapezoidal cross-sectional area.

[0057] According to at least one embodiment, a trench depth is at least 35% or at least 40% or at least 45% of a total thickness of the first leadframe part. Alternatively or additionally, the trench depth is at most 65% or at most 50% of the total thickness.

[0058] According to at least one embodiment, the total thickness of the first leadframe part is at least 100 pm or at least 140 pm. Alternatively or additionally, the total thickness is at most 250 pm or at most 210 pm.

[0059] According to at least one embodiment, a width of the trench is at least 50% or at least 80% of the total thickness of the first leadframe part. Alternatively or additionally, the width is at most 300% or at most 200% or at most 150% of the total thickness. For example, the width of the trench is between 0.1 mm and 0.3 mm inclusive.

[0060] According to at least one embodiment, the first leadframe part is larger than the second leadframe part. For example, the sizes of the leadframe parts differ by at least a factor of 1, 2 or by at least a factor of 1, 5 or by at least a factor of 2 and / or by at most a factor of 10. The size relates in particular to a base area of ​​the leadframe parts as seen from the inside in a plan view. According to at least one embodiment, the second leadframe part comprises a mounting area and / or one or more further solder control points. The mounting area of ​​the second leadframe part is provided, for example, for an ESD protection chip, a control IC and / or a bonding wire connection.

[0061] According to at least one embodiment, the second guide frame part has a constant thickness between the additional solder control point and the mounting area. In other words, the second guide frame part then does not comprise an edge region separated from the mounting area; rather, the mounting area extends to the edge and comprises the at least one additional solder control point.

[0062] According to at least one embodiment, at least one further trench is located between the at least one further solder control point and the mounting region of the second leadframe part. This means that, due to the trench, the second leadframe part is divided into the mounting region and the at least one edge region.

[0063] The statements regarding the trench, the solder control point and the edge region for the first lead frame part apply equally to the further trench, the further solder control point and the further trench of the second lead frame part.

[0064] According to at least one embodiment, the first leadframe part comprises a plurality of edge regions, each of which is separated from the mounting region of the first leadframe part by a trench. Furthermore, a leadframe unit for a housing, as described in connection with one or more of the above-mentioned embodiments, is specified. Features of the leadframe unit are therefore also disclosed for the housing, and vice versa.

[0065] In at least one embodiment, the leadframe unit is provided for a housing, comprising a first leadframe part and a second leadframe part, for an optoelectronic semiconductor chip, wherein

[0066] - the first leadframe part has a mounting area for attaching a semiconductor chip and / or for attaching an electrical connection means and an edge area on a lateral edge of the leadframe unit,

[0067] - the first leadframe part has a trench between the mounting area and the edge area, and

[0068] - the trench is located on an outer side of the first leadframe part and the outer side is designed for a flat solder mounting of the mounting area and the edge area.

[0069] Furthermore, an optoelectronic semiconductor component with a housing, as described in connection with one or more of the above-mentioned embodiments, is specified. Features of the optoelectronic semiconductor component are therefore also disclosed for the housing, and vice versa.

[0070] In at least one embodiment, the optoelectronic semiconductor component comprises the housing and at least one optoelectronic semiconductor chip mounted in the housing. Furthermore, a method for producing a housing, as described in connection with one or more of the above-mentioned embodiments, is specified. Features of the housing are therefore also disclosed for the method, and vice versa.

[0071] In at least one embodiment, the method comprises the following steps, in particular in the order given:

[0072] - Providing a metallic semi-finished product,

[0073] - producing a leadframe assembly with a plurality of leadframe units from the semi-finished product, in particular by means of a two-stage etching process, wherein each etching step is carried out from a main side of the semi-finished product,

[0074] - Creating a housing base body on the lead frame assembly,

[0075] - optionally attaching and electrically contacting the at least one optoelectronic semiconductor chip in the housing,

[0076] - optional filling of the cavities with a filling, and

[0077] - Separation into packages and / or optoelectronic semiconductor components.

[0078] A package described here, an optoelectronic semiconductor component described here, a method described here and a leadframe unit described here are explained in more detail below with reference to the drawings using examples. Like reference symbols indicate like elements in the individual figures. However, no scale is shown; rather, individual elements may be exaggerated for clarity. They show:

[0079] Figure 1 is a schematic perspective view of an embodiment of a lead frame unit described here for the housing described here,

[0080] Figure 2 is a schematic perspective sectional view of an embodiment of a housing described here with the leadframe unit of Figure 1,

[0081] Figure 3 is a schematic perspective bottom view of the housing of Figure 2,

[0082] Figures 4 and 5 are schematic plan views of main sides of the lead frame unit of Figure 1,

[0083] Figure 6 is a schematic sectional view of an embodiment of an optoelectronic semiconductor component described here with the housing of Figure 2,

[0084] Figure 7 is a schematic sectional view of a method step of an embodiment of a method described here for producing the housing described here,

[0085] Figure 8 is a schematic perspective view of a modification of the lead frame unit of Figure 1,

[0086] Figure 9 is a schematic perspective bottom view of a modification of the housing of Figure 2, Figure 10 is a schematic perspective view of an embodiment of a lead frame unit described here for housings described here,

[0087] Figure 11 is a schematic sectional view of an embodiment of a housing described here with the leadframe unit of Figure 10,

[0088] Figure 12 is a schematic perspective view of an embodiment of a lead frame unit described here for the housing described here,

[0089] Figure 13 is a schematic sectional view of an embodiment of a housing described here with the leadframe unit of Figure 12,

[0090] Figure 14 is a schematic perspective view of a modification of the lead frame unit of Figure 12,

[0091] Figure 15 is a schematic perspective view of an embodiment of a lead frame unit described here for the housing described here,

[0092] Figure 16 is a schematic perspective sectional view of an embodiment of a housing described here with the leadframe unit of Figure 15,

[0093] Figure 17 is a schematic perspective view of a modification of the lead frame unit of Figure 15, and Figures 18 and 19 are schematic perspective views of embodiments of lead frame units described here for housings described here.

[0094] Figures 1, 4 and 5 show an example of a leadframe unit 4. The leadframe unit 4 comprises a first leadframe part 41 and a second, smaller leadframe part 42. Optionally, one or more further leadframe parts 83 are present, which can be smaller than the second leadframe part 42. The leadframe parts 41, 42, 83 are made, for example, from a semi-finished sheet metal, such as copper sheet.

[0095] Many of these leadframe units 4 can be combined into a leadframe assembly (not shown). Adjacent leadframe units 4 are then mechanically connected to one another via support webs 48, also referred to as tie bars, until they are separated.

[0096] The leadframe parts 41, 42, 83 are etched from the semi-finished product from two main sides using a two-stage half-etching process and are thus made of the same material and of the same thickness. For example, the half-etching is more extensive from an outer side 44 than from an opposite inner side 43 (see in particular Figures 4 and 5). Thus, the inner side 43 is larger than the outer side 44.

[0097] The outer side 44 is configured for surface mounting of a subsequent housing 2 with the leadframe unit 4 (see also Figures 2 and 3). The inner side 43 of the first leadframe part 41 is configured in a mounting area 45 for attaching an optoelectronic semiconductor chip, such as an LED chip. Accordingly, the second leadframe part 42 serves, on the inner side 42, in particular for attaching a bonding wire and / or an ESD protection diode. In the respective mounting area 45, the leadframe parts 41, 42 have their full thickness.

[0098] The first leadframe part 41 further has an edge region 46, which borders an outer contour of the leadframe unit 4 and is thus partially exposed on an outer side wall of the housing 2 (see Figure 3). The edge region 46 has two solder control points 47, which are formed by pockets on the outer side 44. The solder control points 47 comprise surfaces oriented transversely to the outer side 44, which are designed to be wetted by a solder during assembly of the housing 2.

[0099] Contrary to the illustration in the figures, it is not absolutely necessary for the solder control points 47 to encompass the pockets. It is equally possible for the solder control points 47 to be formed only by surfaces on the outer side walls that are designed for wetting with the solder. This also applies to all other examples.

[0100] Except for an area with the optional pockets, the edge region 46 has the full thickness of the leadframe part 41. Between the edge region 46 and the mounting region 45 of the first leadframe part 41 there is a region of reduced thickness. This region represents a trench 7 which preferably divides the edge region 46 continuously from the mounting region 45 in a straight line. Viewed in cross section, the trench 7 is approximately rectangular. The smaller second leadframe part 42 is free of such a trench, so that the second leadframe part 42 has the full thickness all the way to the outer outline.

[0101] Optionally, several of the solder control points 47 are located on each of the first and / or second leadframe parts 41, 42, for example two solder control points 47 each. As a further option, it is possible for the solder control points 47 to be separated from one another by a slot 72. It is possible for the slot 72 to widen at least on the outer side 44 in the direction away from the solder control points 47, see the second leadframe part 42. Alternatively, the slot 72 can be of constant width, see the first leadframe part 41.

[0102] It is possible for the slot 72 on the first leadframe part 41 to extend into the trench 7. However, the slot 72 only partially penetrates the trench 7 in a direction perpendicular to a longitudinal axis of the trench, see Figures 1 and 4.

[0103] Figure 2 shows that the housing 2, in addition to the leadframe unit 4, also comprises a housing body 5. The housing 2, which according to Figure 2 does not yet comprise a semiconductor chip, can still be present in a housing assembly (not shown), so that the outer side walls 55 are only created when the housing assembly is divided into the individual housings 2 or semiconductor components.

[0104] The housing body 5 forms two cavities 51, 52, wherein each of the leadframe parts 41, 42 and optionally the further leadframe parts 83 are partially exposed due to the cavities 51, 52, so that the inner sides 43 are accessible. The cavities 51, 52 are preferably surrounded by a cavity wall 53. It is possible for the cavity wall 53 to be lower between the cavities 51, 52 than at the outer side walls 55.

[0105] The solder control points 47 are, for example, each completely covered by the associated cavity wall 53. It is possible for the slots 72 to be only partially covered by the respective cavity wall 53. The trench 7, which can be completely or essentially completely filled by the housing body 5, is located on the cavity wall 53. For example, an inner edge of the cavity wall 53 on the inner side 43 and an outer side wall of the trench 7, which is closer to the associated side wall 55, lie in a common plane perpendicular to the inner side 43. This applies, for example, with a tolerance of at most 0.2 mm.

[0106] This position of the trench 7 allows the relatively large first leadframe part 41 to yield to stress, i.e., to exhibit a slight kink along the trench 7. As a result, the edge region 46 adheres better to the cavity wall 53 than in the case of a first leadframe part 41 of constant thickness.

[0107] This division of the first leadframe part 41 into the edge region 46 with the optional solder control points 47 and the mounting region 45 due to the trench 7 is particularly evident in Figure 3: The housing body 5 extends continuously between the edge region 46 and the mounting region 45. The illustration in Figures 1 to 5 is to scale. For example, it is a 2720 component.

[0108] Figure 6 shows an example of an optoelectronic semiconductor component 1 comprising the housing 2 of Figures 2 and 3. The optoelectronic semiconductor chip 3 and the additional semiconductor chip 31, such as an ESD protection chip, are soldered into the cavities 51, 52. Electrical connection is established via electrical connecting means 6, such as bonding wires.

[0109] The trench 7 has a trench depth D that is, for example, between 40% and 60% of a total thickness T of the leadframe parts 41, 42, 83. To ensure a sufficient reduction in the flexural rigidity of the first leadframe part 41 in the region of the trench 7, the trench 7 preferably has a width B such that: 0.8 T < B < 2 T or 1.2 T < B < 1.6 T. This can equally apply in all other examples.

[0110] Figure 6 shows, as a further option, that the cavities 51, 52 can be partially or completely filled with a filling 54. The filling 54 is, for example, a silicone compound that can contain at least one additive, such as light-scattering particles, a phosphor, and / or an optical filter material.

[0111] A manufacturing method for the housings 2 is illustrated schematically in conjunction with Figure 7. The housings 2 are constructed, for example, as described in conjunction with Figures 1 to 5. The leadframe assembly 40, which is half-etched on each of its two main sides and has a plurality of leadframe units 4, is located on a carrier 84, for example a film for film-assisted transfer molding, or FAM for short. The housing assembly 20 is produced on the carrier 84. Adjacent units are subsequently divided along separation lines 82, from which the individual components and the side walls 55 result. The semiconductor chips 3, 31, the electrical connecting means 6 and the optional filling 54 are preferably already placed before the division.

[0112] Furthermore, Figure 7 illustrates that only the areas of the outer side 44 not covered by the housing body 5 are covered by a metal coating 81, such as NiPdAu. This metal coating 81 also covers all exposed surfaces of the pockets that form the solder control points 47. Such a metal coating 81 can be designed by applying the metal coating 81 only after the housing body 5 has been produced.

[0113] Figure 8 shows a modification 94 of the leadframe unit from Figure 1 and Figure 9 shows a modification 92 of the housing from Figure 2, which do not have a trench on the first leadframe part 41. As a result, in a danger zone X, see Figure 6, there is an increased risk that the first leadframe part 41 will not be able to adequately compensate for thermomechanical stresses, particularly during soldering, and will become detached from the housing body 5 in the region of the cavity wall 53. The trenches 7 in the leadframe units 4 described here significantly reduce the risk of such delamination. Figure 10 illustrates a further example of the leadframe unit 4. The associated housing 2 can be seen in Figure 11; the section line to the section in Figure 11 is shown in Figure 10 as a dash-dot line. Unlike the design shown in Figures 1 to 5, the trench 7 is semicircular in cross section and not square.

[0114] As a further option, it is possible for the slot 72 in the first leadframe part 41 to completely penetrate the trench 7 on the outer side 44. Thus, two partial trenches extending from one another are present on the outer side 44. The slots 72 of both leadframe parts 41, 42 can thus have the same shape, except for the trench 7.

[0115] These designs of the trench 7 and the slot 72 are also possible in all other examples.

[0116] The illustration in Figures 10 and 11 is to scale. For example, it shows a 2720 component.

[0117] Furthermore, the statements made with regard to Figures 1 to 7 apply equally to Figures 10 and 11, and vice versa.

[0118] Figure 12 illustrates another example of the leadframe unit 4. The associated housing 2 is shown in Figure 13; the intersection line to the section in Figure 13 is shown in Figure 12 as a dashed-dotted line.

[0119] The first leadframe part 41 has several edge regions 46, each with one of the solder control points 47. Thus, the solder control points 47 of the first leadframe part 41 are present on three side walls of the cubic housing 2, and the further solder control point 49 of the second leadframe part 42 is located on the fourth side wall.

[0120] Thus, three of the trenches 7 are present in the first leadframe part 41. The second leadframe part 42 may be free of a trench.

[0121] Optionally, as in all other examples, the mounting area 45 of the first lead frame part 41 can be provided with corner extensions 85 in order to increase the stability of the housing 2.

[0122] The illustration in Figures 12 and 13 is to scale. For example, it shows a 2720 component.

[0123] Furthermore, the statements made with regard to Figures 1 to 11 apply equally to Figures 12 and 13, and vice versa.

[0124] Figure 14 shows the modification 94 which corresponds to the example in Figure 12 except for the missing trench.

[0125] Figure 15 illustrates another example of the leadframe unit 4. The associated housing 2 is shown in Figure 16; the intersection line to the section in Figure 16 is shown in Figure 15 as a dashed-dotted line.

[0126] The mounting area 45 is elongated, and the solder control points 47, 49 are located on the short sides of the leadframe unit 4. The first leadframe part 41, in turn, has the trench 7.

[0127] In Figure 15, it is shown as a dashed line that the second leadframe part 42 can also have a further trench 71 in order to position the further solder control point 49 in an edge region. Such a further trench 71, to which the explanations regarding trench 7 apply accordingly, can also be present in all other examples, in particular in the designs of Figures 1, 10, 12, 18, and 19.

[0128] The illustration in Figures 15 and 16 is to scale. For example, it shows a 4014 component.

[0129] Furthermore, the statements made with regard to Figures 1 to 14 apply equally to Figures 15 and 16, and vice versa.

[0130] Figure 17 shows the modification 94 which corresponds to the example in Figure 15 except for the missing trench.

[0131] The examples in Figures 18 and 19 are based on the example in Figure 15 and it is shown that the trenches 7 do not necessarily have to be continuous.

[0132] Thus, in the trench 7 of Figure 18, there is a central transverse web 73 which extends through the entire thickness of the first leadframe part 41 through the trench 7. However, in the direction parallel to the longitudinal axis of the trench 7, the transverse web 73 is narrow, so that the buckling capability of the first leadframe part 41 is not significantly reduced by the transverse web 73.

[0133] In contrast, the trench 7 of Figure 19 is provided with two transverse webs 73. The transverse webs 73 are located at the ends of the trench 7 and thus close the trench 7, resulting in a pocket 74. Due to the two transverse webs 73, the pocket 74 can remain free from the housing body 5.

[0134] Such transverse webs 73, as illustrated in Figures 18 and 19, can also be present in all other examples. If additional trenches 71 are present on the second leadframe part 42, such transverse webs 73 can also be used in the additional trenches 71.

[0135] The illustrations in Figures 15 and 16 are to scale. These are, for example, 4014 components.

[0136] Furthermore, the statements made with regard to Figures 1 to 16 apply equally to Figures 17 and 18, and vice versa.

[0137] The components shown in the figures preferably follow one another in the specified order, in particular directly one after the other, unless otherwise stated. Components that are not touching in the figures are preferably spaced apart. If lines are drawn parallel to one another, the associated surfaces are preferably also aligned parallel to one another. Furthermore, the relative positions of the drawn components to one another are correctly reproduced in the figures, unless otherwise stated.

[0138] The invention described here is not limited by the description based on the exemplary embodiments. Rather, the invention encompasses any novel feature and any combination of features, including in particular any combination of features in the patent claims, even if this feature or combination itself is not explicitly stated in the patent claims or exemplary embodiments.

[0139] This patent application claims priority from German patent application 10 2022 112 609.9, the disclosure of which is hereby incorporated by reference.

[0140] Reference symbol list

[0141] 1 optoelectronic semiconductor component

[0142] 2 housings

[0143] 20 Housing composite

[0144] 3 optoelectronic semiconductor chip

[0145] 31 additional semiconductor chips

[0146] 4 Ladder frame unit

[0147] 40 ladder frame composite

[0148] 41 first ladder frame part

[0149] 42 second, in particular smaller ladder frame part

[0150] 43 Inside

[0151] 44 Outside

[0152] 45 Assembly area

[0153] 46 Marginal area

[0154] 47 Soldering control point

[0155] 48 Support bridge

[0156] 49 additional solder control points

[0157] 5 Housing body

[0158] 51 first cavity

[0159] 52 second cavity

[0160] 53 Cavity wall

[0161] 54 Filling especially of the first cavity

[0162] 55 outer side wall

[0163] 6 electrical connector

[0164] 7 ditch

[0165] 71 further ditch

[0166] 72 slot

[0167] 73 Crossbar

[0168] 74 bag

[0169] 81 Metal coating

[0170] 82 Separation line

[0171] 83 additional ladder frame part 84 support

[0172] 85 Corner extension

[0173] 92 Modification of a housing

[0174] 94 Modification of a lead frame unit B Width of the trench

[0175] D Trench depth

[0176] T Total thickness of the ladder frame parts

[0177] X Danger zone

Claims

Patent claims 1. Housing (2) for an optoelectronic semiconductor chip (3) with - a first ladder frame part (41) and a second ladder frame part (42) , - a housing body (5) which mechanically connects the first and second ladder frame parts (41, 42) together, wherein - the first conductor frame part (41) has a mounting area (45) for attaching the semiconductor chip (3) and / or for attaching an electrical connecting element (6) and an edge area (46) on a lateral edge of the housing (2), - the first ladder frame part (41) has a trench (7) between the assembly area (45) and the edge area (46), and - the trench (7) is located on an outer side (44) of the first ladder frame part (41) and the outer side (44) is prepared for mounting the housing (2) and the mounting area (45) and the edge area (46) extend to the outer side (44), - the housing body (5) forms a first cavity (51) and in the first cavity (51) an inner side (45) of the first conductor frame part (41) which is designed for attaching the semiconductor chip (3) is free from the housing body (5), - the edge area (46) is at least partially covered by a cavity wall (53) of the first cavity (51), as seen from a top view of the inside (45), and - viewed from above on the inside (45) all ends of the trench (7) lie within the first cavity (51).

2. Housing (2) according to the preceding claim, wherein the trench (7) extends continuously between the mounting area (45) and the edge area (46).

3. Housing (2) according to claim 1, wherein the groove (7) is formed by one or more crossbars (73) is interrupted and the at least one crossbar (73) is as thick as the mounting area (45) and the edge area (46), wherein a width of the crossbar (73) or the sum of the widths of all crossbars (7) along the trench (7) is at most 40% of a total length of the trench (7) including the at least one crossbar (73).

4. Housing (2) according to one of the preceding claims, wherein the trench (7) is partially or completely filled by the housing body (5).

5. Housing (2) according to one of the preceding claims, wherein the housing body (5) further forms a second cavity (52) so that the inside (45) of the second conductor frame part (42) is exposed.

6. Housing (2) according to one of the preceding claims, wherein, viewed from above on the inside (45), the trench (7) is completely within the first cavity (51).

7. Housing (2) according to one of the preceding claims, wherein, viewed in plan view of the inside (45) and towards the edge region (46), the trench (7) borders the cavity wall (53) of the first cavity (51).

8. Housing (2) according to one of the preceding claims, wherein the edge region (46) comprises at least one solder inspection point (47), the solder inspection point (47) being separated from outer side walls (55) of the housing (2) is freely accessible.

9. Housing (2) according to the preceding claim, wherein a metal coating (81) is applied to the first conductor frame part (41) at least in the area of ​​the solder control point (47).

10. Housing (2) according to one of the two preceding claims, wherein the edge region (46) has several of the solder control points (47) comprises the solder control points (47) being subdivided from each other in a direction transverse to the trench (7) by a slot (72) through the first conductor frame part (41).

11. Housing (2) according to the preceding claim, wherein the slot (72) partially or completely cuts through the trench (7).

12. Housing (2) according to one of the two preceding claims, wherein the slot (72) widens in places in the direction away from the solder control points (47) and in the direction towards the trench (7).

13. Housing (2) according to one of the preceding claims, wherein the trench (7) is at least partially semicircular or square in cross-section.

14. Housing (2) according to one of the preceding claims, wherein a trench depth (D) is at least 35% and at most 65% of a total thickness (T) of the first ladder frame part (41), wherein the total thickness (T) is between 100 pm and 250 pm inclusive.

15. Housing (2) according to one of the preceding claims, wherein a width (B) of the trench (7) is at least 50% and at most 200% of the total thickness (T) of the first ladder frame part (41).

16. Housing (2) according to one of the preceding claims, wherein the first conductor frame part (41) is larger than the second conductor frame part (42), the second conductor frame part (42) comprising a mounting area (45) and a further solder inspection point (49).

17. Housing (2) according to the preceding claim, wherein the second guide frame part (42) has a constant thickness between the further solder control point (49) and the assembly area (45).

18. Housing (2) according to claim 16, in which a further trench (71) is located between the further solder inspection point (49) and the assembly area (45) of the second conductor frame part (42).

19. Housing (2) according to one of the preceding claims, comprising several of the edge regions (46) , each of which is separated by a trench (7) from the mounting area (45) of the first ladder frame part (41).

20. Conductor frame assembly (4) for a housing (2) for an optoelectronic semiconductor chip (3) comprising a first conductor frame part (41) and a second conductor frame part (41), wherein - the first conductor frame part (41) has a mounting area (45) for attaching the semiconductor chip (3) and / or for attaching an electrical connecting means (6) and an edge area (46) on a lateral edge of the conductor frame assembly (4), - the first conductor frame part (41) has a groove (7) between the mounting area (45) and the edge area (46), and - the trench (7) is located on an outer side (44) of the first ladder frame part (41) and the outer side (44) is used for a surface soldered mounting of the mounting area (45) and the is set up in the periphery (46).

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