Semiconductor assembly having a semiconductor element and a substrate

Abstract

The invention relates to an assembly (2) having an electronic component (4) and a substrate (6). To reduce the structural space of such an assembly (2) and allow improved heat dissipation, it is proposed that the substrate (6) has a metallization (10) having at least a first conductor structure (16) and a second conductor structure (18), wherein: the first conductor structure (16) is arranged at least partially within the second conductor structure (18); the electronic component (4) is connected, in particular integrally bonded, to the first conductor structure (16); the electronic component (4) is surrounded by a thermally conductive housing element (8) that is integrally bonded to the second conductor structure (18); and a cover surface (26) and at least one side surface (28) of the electronic component (4) are connected to the housing element (8) via a thermally conductive filler material (24).

Description

[0001] Description

[0002] Semiconductor device with a semiconductor element and a substrate

[0003] The invention relates to an arrangement comprising an electronic component and a substrate.

[0004] Furthermore, the invention relates to a power converter with at least one such arrangement.

[0005] Furthermore, the invention relates to a method for producing an arrangement comprising an electronic component and a substrate.

[0006] Furthermore, the invention relates to a use of segment strips with segments, each having a cavity, for producing housing elements for such an arrangement.

[0007] Such arrangements are used, for example, in a power converter. A power converter can be anything from a rectifier, an inverter, a converter or a DC-DC converter. Active electronic components such as transistors and diodes to passive electronic components such as capacitors, resistors and also sensors can be used in a power converter. Such electronic components are usually connected to a substrate. The electrical performance, and in particular the service life, of the electronic components depends significantly on their thermal cooling. The cooling time plays a decisive role for a high heat flow. Although high heat flows can be achieved with fluid cooling, the cooling solution can be very complex depending on the application. Furthermore, heat spreading plates and heat sinks, for example, require a lot of space.Against this background, it is an object of the present invention to reduce the installation space of such an arrangement and to enable improved heat dissipation.

[0008] This object is achieved according to the invention by an arrangement with an electronic component and a substrate, wherein the substrate has a metallization with at least a first conductor structure and a second conductor structure, wherein the first conductor structure is arranged at least partially within the second conductor structure, wherein the electronic component is connected, in particular materially, to the first conductor structure, wherein the electronic component is surrounded by a thermally conductive housing element which is materially connected to the second conductor structure, wherein a cover surface and at least one side surface of the electronic component is connected to the housing element via a thermally conductive filler material.

[0009] Furthermore, the object is achieved according to the invention by a power converter with at least one such arrangement.

[0010] Furthermore, the object is achieved according to the invention by a method for producing an arrangement with an electronic component and a substrate, wherein the substrate has a metallization with at least a first conductor structure and a second conductor structure, wherein the first conductor structure is arranged at least partially within the second conductor structure, comprising the following steps: inserting the electronic component and a thermally conductive filler material into a thermally conductive housing element, wherein a cover surface and at least one side surface of the electronic component are connected to the housing element via the thermally conductive filler material, connecting the electronic component to the first conductor structure and materially connecting the housing element to the second conductor structure.Moreover, the object is achieved according to the invention by a method for producing an arrangement with an electronic component and a substrate, wherein the substrate has a metallization with at least a first conductor structure and a second conductor structure, wherein the first conductor structure is arranged at least partially within the second conductor structure, comprising the following steps: connecting the electronic component to the first conductor structure and materially connecting a thermally conductive housing element to the second conductor structure, filling a thermally conductive flowable filling material into the housing element, wherein a cover surface and at least one side surface of the electronic component are connected to the housing element via the filling material.

[0011] Furthermore, the object is achieved according to the invention by using, in particular metallic, segment strips with segments, each having a cavity, for producing housing elements for such an arrangement, wherein the segment strips have predetermined breaking points between the segments, in particular with a perforation.

[0012] The advantages and preferred embodiments listed below with regard to the arrangement can be transferred analogously to the power converter, the methods and the use.

[0013] The invention is based on the idea of ​​improving the heat dissipation of an electronic component which is connected to a substrate via an additional heat path. In addition to the heat dissipation via the substrate, an additional heat path is created via a thermally conductive housing element which surrounds the electronic component. The thermally conductive housing element can be made, among other things, from a metallic material, e.g. copper, aluminum or one of their alloys, a thermally conductive plastic or a ceramic material. A thermal connection between the electronic component and the thermally conductive housing element is created via a thermally conductive filler material, wherein a cover surface and at least one side surface of the electronic component are connected to the housing element via the filler material.For example, the housing element has an inner housing wall that is connected to the filler material. The thermally conductive filler material can be electrically insulating or electrically conductive.

[0014] The substrate has a metallization with at least a first conductor structure and a second conductor structure, wherein the first conductor structure is at least partially arranged within the second conductor structure. For example, the second conductor structure comprises a conductor track which partially surrounds a conductor track of the first conductor structure. Such a conductor track of the second conductor structure can, among other things, be elliptical, round, rectangular or square, run around the first conductor structure and have at least one interruption. In particular, the second conductor structure is arranged electrically insulated from the first conductor structure. The substrate can, among other things, be designed as a DGB (Direct Copper Bonded) substrate. The electronic component is connected to the first conductor structure, in particular in a materially bonded manner.For example, the electronic component is connected to the first conductor structure by soldering, sintering or adhesively. The thermally conductive housing element is materially connected to the second conductor structure, e.g. by soldering, sintering or adhesively. Alternatively, the electronic component can be connected to the first conductor structure in a force-fitting manner by pressing, e.g. by the housing element. With such an arrangement, which has low contact resistance, any heat loss generated during operation of the electronic component can additionally be dissipated to the substrate or to the environment via the thermally conductive filler material and the thermally conductive housing element. Furthermore, installation space is saved by the thermally conductive housing element and the thermally conductive filler material.

[0015] A further embodiment provides that the thermally conductive filler material is flowable, at least during operation of the electronic component. In particular, the thermally conductive filler material is implemented as a liquid. This results in low contact resistance and thus very good thermal conductivity.

[0016] A further embodiment provides for the electronic component to be encapsulated by the housing element, in particular in a fluid-tight manner. Such encapsulation prevents the thermally conductive filler material from escaping, thus facilitating maintenance and increasing service life. Furthermore, such an encapsulated arrangement makes it possible to at least partially eliminate the need for additional housing components, thus further saving installation space.

[0017] Another embodiment provides for the thermally conductive filler material to be electrically insulating. In particular, the thermally conductive filler material is implemented as an inert liquid. Examples include Galden® HS 240, 3M™ Novec™, or 3M™ Fluorinert™, as well as paraffins. Such inert liquids can have a high dielectric strength of at least 10 kV / mm, in particular 20 kV / mm. Furthermore, the use of electrically insulating liquids results in low contact resistance and very good thermal conductivity.

[0018] A further embodiment provides that an intermediate space between the electronic component and the housing element is completely filled with the thermally conductive filler material. This achieves optimized insulation properties and saves installation space. Furthermore, the contact resistance is reduced, which leads to improved heat dissipation. A further embodiment provides that the thermally conductive filler material is electrically conductive. For example, the thermally conductive filler material comprises a liquid metal. The liquid metal can contain, among other things, gallium and / or indium. A thermal conductivity of the filler material of at least 40 W / mK, in particular 60 W / mK, can thus be achieved.

[0019] A further embodiment provides for the filler material to be arranged so as to be electrically insulated from a contact area of ​​the electronic component with the substrate by means of an electrically insulating material. The electrically insulating material can contain, among other things, silicone or a resin. Such an arrangement prevents short circuits while achieving high thermal conductivity.

[0020] A further embodiment provides that the electrically insulating material is at least part of a sealing element. For example, the sealing element is bonded, in particular adhesively, to an inner housing wall and side surfaces of the electronic component. In particular, the filling material is encapsulated in a fluid-tight manner around the electronic component by the housing element and the sealing element. This prevents short circuits while achieving high thermal conductivity.

[0021] A further embodiment provides that the housing element has at least one spacer element which is in contact with the electronic component. In particular, the at least one spacer element is connected to an inner housing surface. Among other things, at least one spacer element can be conical, cuboidal or cylindrical. The electronic component is held by at least one such spacer element, whereby mechanical stability is increased during the joining process, in particular before connection to the substrate. A further embodiment provides that the housing element has a closable opening for filling the thermally conductive filler material, which is designed to be flowable. Such an opening makes the housing element particularly easy to fill.

[0022] A further embodiment provides that the housing element has ribs, in particular at least on a side facing away from the substrate. Such ribs enlarge the housing surface toward the surroundings, thus enabling improved heat dissipation.

[0023] In the following, the invention is described and explained in more detail with reference to the exemplary embodiments shown in the figures.

[0024] It shows :

[0025] FIG 1 is a schematic sectional view of a first embodiment of an arrangement,

[0026] FIG 2 is a schematic sectional view of a second embodiment of an arrangement,

[0027] FIG 3 is a schematic sectional view of a third embodiment of an arrangement,

[0028] FIG 4 is a schematic sectional view of a fourth embodiment of an arrangement,

[0029] FIG 5 is a schematic representation of a method for producing an arrangement,

[0030] FIG 6 is a schematic sectional view of a fifth embodiment of an arrangement,

[0031] FIG 7 is a schematic sectional view of a sixth embodiment of an arrangement, FIG 8 is a schematic view of segment strips for producing housing elements for an arrangement,

[0032] FIG 9 is a schematic sectional view of a seventh embodiment of an arrangement,

[0033] FIG 10 is a schematic sectional view of an eighth embodiment of an arrangement,

[0034] FIG 11 is a schematic diagram of a power converter.

[0035] The exemplary embodiments explained below are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual features of the invention that are to be considered independently of one another. These also further develop the invention independently of one another and are thus to be regarded as components of the invention, either individually or in a combination other than that shown. Furthermore, the described embodiments can also be supplemented by further features of the invention already described.

[0036] The same reference symbols have the same meaning in the different figures.

[0037] FIG 1 shows a schematic sectional view of a first embodiment of an arrangement 2, which is designed as a power arrangement and comprises an electronic component 4, a substrate 6 and a thermally conductive housing element 8. The electronic component 4 is designed, for example, as a lateral power semiconductor, in particular with a wide band gap. Such power semiconductors can be realized, for example, using silicon carbide or gallium nitride technology. Alternatively, the electronic component 4 can be designed, among other things, as another power semiconductor, such as an IGBT or vertical SiC MOSFET, as a diode or as a passive component, e.g. as a shunt resistor. The substrate 6 has a metallization 10 on a side facing the electronic component 4 and a further metallization 12 on a side facing away from the electronic component 4.The metallizations are mechanically and thermally conductively connected via a dielectric material layer 14, which may contain, for example, aluminum oxide or aluminum nitride. In particular, the substrate 6 is designed as a DCB (Direct Copper Bonded) substrate. The metallization 10 comprises a first conductor structure 16 and a second conductor structure 18 arranged such that it is electrically insulated from the first conductor structure 16, wherein the first conductor structure 16 is arranged at least partially within the second conductor structure 18. The electronic component 4 has contacting elements 22, for example pins, on a base area 20, via which contacting elements the electronic component 4 is materially connected, for example via a soldered or sintered connection, to the first conductor structure 16 of the metallization 10. The electronic component 4, designed as a power semiconductor, can be connected to the substrate 6 in a package or "bare die".

[0038] The electronic component 4 is arranged in the thermally conductive housing element 8 and is thus surrounded by it. The thermally conductive housing element 8 is made, for example, from a metallic material, e.g. copper, aluminum or one of their alloys, a thermally conductive plastic or a ceramic material. Furthermore, the housing 8 is materially connected, for example adhesively, to the second conductor structure 18 of the metallization 10. The adhesive connection is produced by means of a thermally conductive adhesive. If the housing 8 is made from a metallic material at least in the region of the contact with the metallization 10, the materially bonded connection can alternatively be produced by soldering or sintering. The electronic component 4 is encapsulated, in particular in a fluid-tight manner, by the materially bonding of the housing element 8 to the second conductor structure 16.

[0039] A thermally conductive filler material 24 is arranged in the thermally conductive housing element 8. The thermally conductive filler material 24, which is flowable at least during operation of the electronic component 4, is arranged. The thermally conductive filler material 24 is designed in FIG. 1 as an electrically insulating inert liquid. Examples of such inert liquids include Galden® HS 240, 3M™ Novec™, 3M™ Fluorinert™. Additionally or alternatively, the thermally conductive filler material 24 can contain a paraffin. In particular, the thermally conductive filler material 24 has a dielectric strength of at least 10 kV / mm.The electronic component 4, which is essentially cuboid-shaped, for example, has a top surface 26 and side surfaces 28 in addition to the base surface 20, wherein both the top surface 26 and the side surfaces 28 of the electronic component 4 are completely contacted with the thermally conductive filler material 24 and are connected to an inner housing wall 30 of the housing element 8 via the thermally conductive filler material 24. By way of example, in FIG 1 an intermediate space 32 between the electronic component 4 and the housing element 8 is completely filled with the thermally conductive and electrically insulating filler material 24. In this way, any heat loss arising during operation of the electronic component 4 can additionally be dissipated to the environment via the thermally conductive filler material 24 and the thermally conductive housing element 8.In addition, the further metallization 12 of the substrate 6 can be connected over its entire surface to a heat sink 34, in particular a heat sink. The heat loss occurring during operation of the electronic component 4 can thus be dissipated via the thermally conductive filler material 24, the thermally conductive housing element 8 and the substrate 6 to the heat sink 34 which is connected over its entire surface to the further metallization 12 of the substrate 6. FIG 2 shows a schematic sectional view of a second embodiment of an arrangement 2, wherein the thermally conductive filler material 24 is designed to be electrically conductive. For example, liquid metal is used as the electrically and thermally conductive filler material 24. In order to avoid short circuits, the filler material 24 is arranged so as to be electrically insulated from a contact region 38 of the electronic component 4 with the substrate 6 by means of an electrically insulating material 36.The electrically insulating material 36 may contain, among other materials, underfill, plastic, or silicone. The further design of the arrangement 2 in FIG. 2 corresponds to the design in FIG. 1.

[0040] FIG 3 shows a schematic sectional view of a third embodiment of an arrangement 2. An electrically insulating material 36 is designed as a sealing element 40, which prevents contact between the electrically and thermally conductive filler material 24, which is flowable at least when the electronic component 4 is in operation, and the contacting elements 22 of the electronic component 4. For example, the sealing element 40 is connected, in particular adhesively, to the housing inner wall 30 and the side surfaces 28 of the electronic component 4. The filler material 24 is encapsulated in a fluid-tight manner around the electronic component 4 by the housing element 8 and the sealing element 40. The further embodiment of the arrangement 2 in FIG 3 corresponds to the embodiment in FIG 2.

[0041] FIG. 4 shows a schematic sectional view of a fourth embodiment of an arrangement 2, wherein the housing element 8 has spacer elements 41 on the housing inner wall 30, which are contacted with the electronic component 4. The spacer elements 41, which are designed, for example, conically or alternatively cuboidally or cylindrically, hold the electronic component 4 and increase the mechanical stability during the joining process, in particular before connecting to the substrate 6. The further embodiment of the arrangement 2 in FIG. 4 corresponds to the embodiment in FIG. 1.

[0042] FIG 5 shows a schematic representation of a method for producing an arrangement 2. The method comprises the following steps:

[0043] Inserting A an electronic component 4 and a thermally conductive filler material 24 into a thermally conductive housing element 8, wherein a cover surface 26 and the side surfaces 28 of the electronic component 4 are connected to the housing element 8 via the thermally conductive filler material 24. The thermally conductive filler material 24 used is electrically conductive and flowable at least when the electronic component 4 is in operation. For example, liquid metal is used as the electrically and thermally conductive filler material 24. The electronic component 4 is inserted in such a way that the contacting region 38 of the electronic component 4 with the contacting elements 22 is not in contact with the liquid metal.

[0044] In a further step, the liquid metal is sealed B against the contacting region 38 of the electronic component 4 with a sealing element 40 which contains an electrically insulating material 36.

[0045] In a further step, a connection C of the electronic component 4 to the first conductor structure 16 of the metallization 10 of the substrate 6 and a materially bonding D of the housing element 8 to the second conductor structure 18 of the metallization 10 of the substrate 6 takes place. The connection C and the materially bonding D can take place by soldering, sintering or adhesively, e.g. by means of an electrically conductive glue. Alternatively, the connection C of the electronic component 4 can take place by pressing. For the pressing, for example, elastic connecting elements such as springs or brackets can be used. The further embodiment of the arrangement 2 in FIG. 5 corresponds to the embodiment in FIG. 3.

[0046] FIG. 6 shows a schematic sectional view of a fifth embodiment of an arrangement 2, wherein a filling E of a thermally conductive, flowable filling material 24 into the thermally conductive housing element 8 takes place after the connection C of the electronic component 4 to the first conductor structure 16 and the materially bonded connection D of the thermally conductive housing element 8 to the second conductor structure 18 via an opening 42. After the opening 42 is closed, the electronic component 4 is encapsulated, in particular in a fluid-tight manner. The further embodiment of the arrangement 2 in FIG. 6 corresponds to the embodiment in FIG. 1.

[0047] FIG. 7 shows a schematic sectional view of a sixth embodiment of an arrangement 2. The first conductor structure 16 of the metallization 10 is guided via vias 44 to a side 46 of the substrate 6 facing away from the electronic component 4. The further embodiment of the arrangement 2 in FIG. 7 corresponds to the embodiment in FIG. 1.

[0048] FIG. 8 shows a schematic representation of, for example, metallic, segment strips 48 for producing housing elements 8 for an assembly 2, wherein the segment strips 48 have predetermined breaking points 50, for example with a perforation 52, for producing housing elements 8 from the segments. A cavity 56 for receiving an electronic component 4 is provided in each of the segments 54 of the segment strips 48.

[0049] FIG 9 shows a schematic sectional view of a seventh embodiment of an arrangement 2, wherein the housing element 8 is made from, for example, three segments 54, each having a cavity 56. Electronic components 4 of different heights h1, h2, h3 are arranged in the cavities 56. The thermally conductive filler material 24 compensates for different heights h1, h2 of the electronic components 4, which are designed, for example, as power semiconductors, as long as the height h1, h2 does not exceed a depth t of the cavity 56. If an electronic component 4, e.g. a passive component such as a capacitor, with a height h3 exceeds the depth t of the cavity 56, an opening 42 can be inserted so that the electronic component 4 projects beyond the housing element 8 with a height h3.

[0050] FIG 10 shows a schematic sectional view of an eighth embodiment of an arrangement 2, wherein the housing element 8 has ribs 58 on a side facing away from the substrate 6, which ribs 58 enlarge the housing surface towards the environment and thus enable improved heat dissipation.

[0051] FIG 11 shows a schematic representation of a power converter 60, which for example has an arrangement 2.

[0052] In summary, the invention relates to an arrangement 2 with an electronic component 4 and a substrate 6. In order to reduce the installation space of such an arrangement 2 and to enable improved heat dissipation, it is proposed that the substrate 6 has a metallization 10 with at least a first conductor structure 16 and a second conductor structure 18, wherein the first conductor structure 16 is arranged at least partially within the second conductor structure 18, wherein the electronic component 4 is connected, in particular in a material-locking manner, to the first conductor structure 16, wherein the electronic component 4 is surrounded by a thermally conductive housing element 8 which is material-lockingly connected to the second conductor structure 18, wherein a cover surface 26 and at least one side surface 28 of the electronic component 4 is connected to the housing element 8 via a thermally conductive filler material 24.

Claims

Patent claims 1. Arrangement (2) with an electronic component (4) and a substrate (6), wherein the substrate (6) has a metallization (10) with at least a first conductor structure (16) and a second conductor structure (18), wherein the first conductor structure (16) is arranged at least partially within the second conductor structure (18), wherein the electronic component (4) is connected, in particular in a material-to-material manner, to the first conductor structure (16), wherein the electronic component (4) is surrounded by a thermally conductive housing element (8) which is material-to-materially connected to the second conductor structure (18), wherein a cover surface (26) and at least one side surface (28) of the electronic component (4) are connected to the housing element (8) via a thermally conductive filler material (24).

2. Arrangement (2) according to claim 1, wherein the thermally conductive filling material (24) is flowable at least at the time of operation of the electronic component (4).

3. Arrangement (2) according to one of claims 1 or 2, wherein the electronic component (4) is encapsulated by the housing element (8), in particular in a fluid-tight manner.

4. Arrangement (2) according to one of claims 1 to 3, wherein the thermally conductive filling material (24) is electrically insulating.

5. Arrangement (2) according to claim 4, wherein an intermediate space (32) between the electronic component (4) and the housing element (8) is completely filled by the thermally conductive filling material (24).

6. Arrangement (2) according to one of claims 1 to 3, wherein the thermally conductive filling material (24) is electrically conductive.

7. Arrangement (2) according to claim 6, wherein the filling material (24) is arranged to be electrically insulated from a contacting region (38) of the electronic component (4) with the substrate (6) via an electrically insulating material (36).

8. Arrangement (2) according to claim 7, wherein the electrically insulating material (36) is at least part of a sealing element (40).

9. Arrangement (2) according to one of the preceding claims, wherein the housing element (8) has at least one spacer element (41) which is in contact with the electronic component (4).

10. Arrangement (2) according to one of the preceding claims, wherein the housing element (8) has a closable opening (42) for filling (E) the thermally conductive filling material (24), which is designed to be flowable.

11. Arrangement (2) according to one of the preceding claims, wherein the housing element (8), in particular at least on a side facing away from the substrate (6), has ribs (58).

12. Power converter (60) with at least one arrangement (2) according to one of the preceding claims.

13. A method for producing an arrangement (2) with an electronic component (4) and a substrate (6), wherein the substrate (6) has a metallization (10) with at least a first conductor structure (16) and a second conductor structure (18), wherein the first conductor structure (16) is arranged at least partially within the second conductor structure (18), comprising the following steps: Inserting (A) the electronic component (4) and a thermally conductive filler material (24) into a thermally conductive housing element (8), wherein a cover surface (26) and at least one side surface (28) of the electronic component (4) are connected to the housing element (8) via the thermally conductive filler material (24), connecting (C) the electronic component (4) to the first conductor structure (16) and materially connecting (D) the housing element (8) to the second conductor structure (18).

14. The method according to claim 13, wherein a thermally conductive filling material (24) is used which is flowable at least at the time of operation of the electronic component (4).

15. Method according to one of claims 13 or 14, wherein the electronic component (4) is encapsulated, in particular fluid-tight, by the material-locking connection (D) of the housing element (8) to the second conductor structure (18).

16. The method according to any one of claims 13 to 15, wherein the thermally conductive filler material (24) is electrically conductive, wherein the filler material (24) is arranged to be electrically insulated from a contacting region (38) of the electronic component (4) with the substrate (6) via an electrically insulating material (36).

17. Method according to one of claims 13 to 16, wherein after the insertion (A) a sealing (B) of the filling material (24) with respect to a contacting area (38) of the electronic component (4) takes place.

18. A method for producing an arrangement (2) with an electronic component (4) and a substrate (6), wherein the substrate (6) has a metallization (10) with at least a first conductor structure (16) and a second conductor structure (18), wherein the first conductor structure (16) is arranged at least partially within the second conductor structure (18), comprising the following steps: Connecting (C) the electronic component (4) to the first conductor structure (16) and materially connecting (D) a thermally conductive housing element (8) to the second conductor structure (18), filling (E) a thermally conductive flowable filling material (24) into the housing element (8), wherein a cover surface (26) and at least one side surface (28) of the electronic component (4) are connected to the housing element (8) via the filling material (24).

19. Use of, in particular metallic, segment strips (48) with segments (54), each having a cavity (56), for producing housing elements (8) for an arrangement (2) according to one of claims 1 to 11, wherein the segment strips (48) have predetermined breaking points (50) between the segments (54), in particular with a perforation (52).

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