DE102011101052A1 - Substrate with electrically neutral region - Google Patents

Abstract

The invention relates to a substrate for receiving at least one electronic element, in particular at least one semiconductor element, comprising an electrically conductive first layer for contacting the element, a thermally conductive second layer for dissipating heat from the element and an electrically insulating third layer, which is between the first layer and the second layer is arranged so that the third layer electrically insulates the first layer from the second layer, the third layer being a thin layer or a glass ceramic or a polymer matrix filled with ceramic powder. The invention also relates to an electronic component, in particular a semiconductor component, comprising at least one semiconductor element and such a substrate, the semiconductor element being electrically conductively connected on a first side to the first layer, preferably via a solder, a conductive adhesive or a silver sintered connection and a A method for producing such a substrate, a third electrically insulating layer being applied to a first electrically conductive layer by sputtering, vapor deposition, physical vapor deposition (PVD), chemical vapor deposition (CVD), lamination, gluing, soldering or a printing process, in particular a screen printing process and that a second thermally conductive layer is applied to the third layer by PVD, sputtering, lamination, gluing, soldering, low-temperature silver sintering or a printing process, in particular a screen printing process, in such a way that the second layer is the first layer has no electrical contact.

Description

The invention relates to a substrate for receiving at least one electronic element, in particular at least one semiconductor element.

The invention also relates to an electronic component, in particular a semiconductor component, comprising at least one semiconductor element and such a substrate as well as a method for producing such a substrate.

Components such as integrated circuits are often applied in layers to substrates in order to achieve a compact design. Due to the compact design, different interconnections and components, such as chips and LEDs can be realized in a small space. The semiconductor elements must be contacted in a small space to supply the semiconductor element with a voltage.

From the DE 196 25 622 A1 a semiconductor device is known in which a contact is arranged on both sides in order to supply the integrated semiconductor element with a voltage. Between the two contacts, the semiconductor element comprises a plurality of layers, here a plurality of differently doped semiconductor layers. The structure is supported by two electrical terminals that are electrically separated from each other by a distance. One of the contacts is connected to an electrically conductive adhesive or a solder directly to one of the electrical connections. The other contact is connected via a bonding wire to the other electrical connection.

A disadvantage of this is that at a high power consumption of the semiconductor element, the electrical power converted by the semiconductor element must be dissipated as heat in order to create stable working conditions for the semiconductor element or to prevent it being destroyed. For this purpose, a cooling device must be attached to the semiconductor device, but this reduces the advantage of the small size of the semiconductor element.

From the DE 10 2009 000 882 A1 a substrate for receiving an electronic element is known, in which an electrically conductive layer is provided for electrical contacting of the element. On the opposite side of the elements of the conductive layer, an electrically insulating connection layer is arranged, which connects a substrate body made of metal with the electrically conductive layer. The bonding layer is composed of a matrix formed of a preceramic polymer. By way of the connection layer, good cooling of the electronic element is to take place through the metallic substrate body which is separated from the electrically conductive layer.

The disadvantage of this is that the structure of the matrix is complicated and the matrix formed is not homogeneous. This can cause the formed substrate to be mechanically unstable and the heat conduction through the substrate to be uneven and thereby limited. For many applications, the cooling by the substrate is not enough. A further disadvantage is that the matrix ages too rapidly in blue and ultraviolet light, so that use of the substrate with many, in particular white LEDs as elements is unfavorable or at least leads to a short lifetime of the manufactured components. It is also disadvantageous that the preceramic material for building the ceramic matrix must be processed at high temperatures, whereby the substrate is thermally stressed and the choice of materials for the substrate is limited. Namely, the reaction pyrolysis for converting the preceramic material into a ceramic matrix is usually carried out at temperatures between 800 ° C and 1600 ° C.

Due to high temperatures or temperature differences during the production of the substrate (the substrates produced must also cool again after production), a thermal stress is always exerted on compounds of different materials or the materials must be matched to each other in terms of their thermal expansion coefficient, or intermediate layers must be applied. Any interlayer is a thermal resistance and therefore undesirable. If the materials are matched, they are severely limited in their choice, especially as they must also be temperature-stable. Many materials, especially the metals used, very particularly thin layers thereof, are not stable under oxidizing atmosphere at high temperatures, so that either these materials can not be used, or the structure of the substrate has to be carried out under protective gas.

The object of the invention is therefore to overcome the disadvantages of the prior art. In particular, a stable substrate is to be provided which enables effective cooling of an element mounted thereon. Also, safer process management for fabricating the substrate is also desirable, as is lesser waste in fabricating the substrate. A lower necessary temperature in building the substrate would also be advantageous.

It is also an object of the invention that the substrate or the semiconductor device easy to install. In this case, the application of the semiconductor devices on boards or the installation in electrical circuits on a circuit board or circuit board should be particularly easy to perform. Improving the cooling performance through the substrate would also allow for further miniaturization of power devices. It is also intended to provide a substrate for electronic elements having an electrically neutral region.

For many applications, especially when the semiconductor elements are LEDs, it would also be advantageous if the materials used do not age too fast by blue light or ultraviolet light.

The object of the invention is achieved by a substrate for accommodating at least one electronic element, in particular at least one semiconductor element, comprising an electrically conductive first layer for contacting the element, a thermally conductive second layer for dissipating heat from the element and an electrically insulating third layer between the first layer and the second layer is arranged such that the third layer electrically isolates the first layer from the second layer, wherein the third layer is a thin layer.

By a thin film is meant a layer of a solid in the micrometer or even nanometer range. The separation of the first and second layers by a thin layer allows a variety of new technical possibilities. On the one hand, the thermal resistance is significantly reduced and on the other hand, other materials can be used, which would be out of the question as thick film. As a result, the material of the third layer can be matched to the materials of the first and second layer, thus achieving a further improvement in the thermal conductivity and / or the mechanical stability of the substrate.

An element is a chip and / or partially differently doped semiconductor, which are contacted as electronic functional elements by the substrate. The electronic element incorporated in the substrate together according to the invention form a component which can be installed ready for use in circuits on boards or printed circuit boards. A component thus differs from an element in the sense of the present invention in that the component comprises the substrate and an element contacted with the substrate, such as an integrated circuit on a chip. In the present case, a built-in element is to be understood as an element applied to the first layer of the substrate, that is to say adhesively bonded, soldered or similarly mechanically fastened and contacted. The installation takes place in such a way that the electronic element can fulfill its function.

It may also be provided according to the invention in such a substrate that the thickness of the third layer is less than 10 μm, preferably less than 5 μm, particularly preferably less than 2 μm.

At such thicknesses, electrical insulators with average or even low heat conduction may also be used as materials for the third layer. On the other hand, the cooling performance achievable by a substrate constructed in this way, when using a highly thermally conductive electrical insulator, is particularly high. Thin films often have a different, more suitable thermal conduction behavior as a solid body of the same material.

It can also be provided that the third layer is applied to the first layer by sputtering, vapor deposition, physical vapor deposition (PVD) or chemical vapor deposition (CVD).

These coating methods are particularly suitable for applying the third layer to the first layer as a thin layer. The coupling to the first layer is particularly good in these methods and thus the thermal resistance of the interface is particularly low.

Furthermore, it can be provided according to the invention particularly preferred that the third layer consists of AlN or Al ₂ O ₃ .

These two materials have a particularly good thermal conductivity and good electrical insulation properties for an insulator and are therefore particularly preferred. In addition, aluminum alloys and aluminum (Al) are particularly suitable as the first and / or second layer, particularly due to their electrical and mechanical properties and machinability and availability, producing a particularly good, mechanically stable compound with AlN or Al ₂ O ₃ on such layers leaves. Owing to the interfacial properties of these materials and the oxide layer which is always present on Al or Al alloys, the interfaces of these materials result in particularly low thermal resistance.

The object of the invention is also achieved by a substrate for receiving at least one electronic element, in particular at least one semiconductor element, comprising an electrically conductive first layer for contacting the element, a heat-conducting second layer for Dissipating heat from the element and an electrically insulating third layer disposed between the first layer and the second layer so that the third layer electrically isolates the first layer from the second layer, wherein the third layer is a glass-ceramic.

The use of a glass ceramic is especially preferred because of its homogeneity and the resulting uniform heat conduction. The glass ceramic can be done for example by lamination of a glass-ceramic inlay. The glass ceramic or the inlay can be, for example, a low-temperature cofired ceramic (LTCC), a high-temperature cofired ceramic (HTCC) or an AlN ceramic.

When using a glass ceramic as the third layer, it can be provided that the third layer is applied to the first layer by a printing process, in particular a screen printing process, and baked in the substrate, preferably melted onto the first layer.

With the printing process, the glass-ceramic layer can be applied particularly easily and quickly. The firing or melting improves the homogeneity of the third layer, in particular with respect to the uniformity of the thickness of the glass-ceramic layer, and produces a stable connection to the first and / or second layer.

The object of the invention is further achieved by a substrate for receiving at least one electronic element, in particular at least one semiconductor element, comprising an electrically conductive first layer for contacting the element, a heat-conducting second layer for dissipating heat from the element and an electrically insulating third layer, disposed between the first layer and the second layer so that the third layer electrically isolates the first layer from the second layer, wherein the third layer is a ceramic powder-filled polymer matrix.

The advantage of using a ceramic powder filled polymer matrix is that the polymer can be processed at relatively low temperatures of less than 300 ° C. At these low temperatures, the substrate is less heavily loaded. Thus, for the production of the substrate, it is then possible to use materials which are only stable up to the temperatures which are above the temperature at which the polymer is processed in order to form the third layer. This is based on the surprising finding that there is no need for a robust ceramic matrix for the formation of the third layer, but also a softer matrix, such as a polymer matrix can be used.

When using a ceramic powder-filled polymer matrix as the third layer can be provided, the polymer of the polymer matrix, a silicone or a resin, preferably an epoxy resin, acrylic resin, silicone resin, more preferably Silikoftal ^® or is a silicone-polyester resin and / or the ceramic powder is an Al ₂ O ₃ powder, an AlN powder and / or a BN (boron nitride) powder.

These materials can be used particularly well to form a stable and electrically well insulating third layer. The polymers mentioned are particularly easy to process, are inexpensive and readily available.

When using a ceramic matrix filled with ceramic powder as the third layer may further be provided that in the polymer matrix, a plurality of spacers are provided, so that the third layer has a defined and uniform thickness, which is determined by the thickness of the Spacer is given, wherein the spacers are in particular spherical and preferably made of glass, SiO ₂ glass, Al ₂ O ₃ , AlN, BN and / or SiN.

By using spacers, which are preferably formed as ceramic and / or glass beads, a uniform thickness of the third layer can be ensured even in difficult production conditions. For example, uneven pressure on the second layer, which can easily occur in mass production, does not affect the third layer to become unevenly thick. For this purpose, a sufficient number of spacers must be provided in the polymer matrix. A sufficient number may for example be three to one hundred spacers, preferably three to eight spacers per substrate. If the spacers are mixed into the raw material (polymer, possibly also already mixed with the ceramic powder) prior to the application of the third layer, the density should be selected such that statistically at least three spacers are contained in every third layer.

In the case of all listed substrates according to the invention having a thin layer or glass ceramic as the third layer, it can be provided according to the invention that the second layer is metallic or comprises a metal core.

Metals have a particularly good heat conduction, therefore, the use of a metal is particularly preferred. In this case, aluminum (Al) or copper (Cu) or aluminum or copper alloys are particularly preferred as metal for the second layer due to their particularly high thermal conductivity.

In the case of all substrates according to the invention, it may further be provided that the third layer and the second layer are arranged in a depression of the first layer and the third layer covers the first layer and the second layer at least partially covers the third layer in the depression.

It can be provided that the thickness of the third layer and the second layer together corresponds to the depth of the depression, so that the surface of the second layer lies in a, in particular planar plane with the first layer outside the depression.

The recess protects the second and especially the third layer. A planar construction of the substrate on the bottom also leads to an easy installation of the substrate according to the invention or the substrate according to the invention with built-in element (of the manufactured component). As a result, a mass production of circuits with such substrates or components is greatly simplified.

A further embodiment of the invention provides substrates in which the second layer is bonded to the third layer by PVD, sputtering, lamination, gluing, soldering, low-temperature silver sintering or a printing process, in particular a screen printing process.

The second layers produced by these methods meet different requirements for use in mass production, the mechanical stability of the substrate and the thermal conductivity of the substrate, that is, the achievable with the substrate cooling performance for an applied to the substrate element.

It can also be provided that the third layer only partially covers the first layer and / or the second layer only partially covers the third layer.

This construction can ensure that no electrically conductive connection between the first and second layer is formed. The electrically neutral region created by the third layer is necessary to prevent or degrade the electronic circuitry of the device.

According to a further particularly preferred embodiment of the invention, it may be provided that the first layer is subdivided into two regions which are electrically insulated from one another, so that the element can be contacted with the two regions.

It can be provided that the regions of the first layer are electrically insulated from each other by a recess in the first layer.

Furthermore, it can be provided that an electrical voltage can be applied to the element over the regions.

Through these structures, it is achieved that the power supply for the electronic element can be completely carried out via a substrate according to the invention.

According to a further particularly preferred embodiment of the invention, it can also be provided that the third layer has a thermal conductivity of more than 5 W / m K, preferably more than 30 W / m K, more preferably more than 100 W / m K.

Such high thermal conductivities enable a strong cooling performance of the elements used in the substrate according to the invention and thus a high possible power consumption of the elements.

It can also be provided that the third layer is homogeneous, in particular consists of only one solid material.

The homogeneity simplifies the manufacturability of the third layer and leads to an improvement in the thermal conductivity of the transition into the second layer for cooling the element.

The handling of the substrate is improved if it is provided that a carrier film, in particular a plastic film, is arranged on the first layer.

It can be provided that the carrier film is arranged on the, the third layer opposite side.

It can also be provided that the carrier film comprises openings for each element.

It can also be provided that the carrier film comprises one or two additional openings for each element.

Furthermore, it can be provided that the additional openings are arranged in a different area of the first layer than the area of the opening for the element. This can be realized in a partially divided first layer.

The carrier film facilitates the construction and thus the production of the substrate, provides additional stabilization and protection of the substrate Substrate. The openings also mark the positions where elements can be inserted and to which bonding wires can be applied and thus facilitate the usability of a substrate according to the invention.

The object of the invention is also achieved by an electronic component, in particular semiconductor component comprising at least one semiconductor element and a substrate according to the invention, wherein the semiconductor element is electrically conductively connected on a first side with the first layer, preferably via a solder, a conductive adhesive or a silver sintered compound.

Semiconductor elements, in particular power semiconductor elements, can be used particularly well together with substrates according to the invention. The surface contact facilitates the transfer of heat from the element into the first layer and then into the third and second layer.

It can be provided that the at least one semiconductor element is contacted on a second side via a bonding wire with the first layer, so that an electrical voltage between the first and second sides of the semiconductor element can be applied, wherein the first layer is divided into at least two areas and the two sides of the semiconductor element are connected to different regions of the first layer.

The electronic component and the semiconductor element of the component are then particularly easy contacted by the substrate.

Electronic components according to the invention can be distinguished by the fact that the at least one semiconductor element is a chip or an LED.

Chips and LEDs often convert a lot of electrical power and are therefore particularly well suited as semiconductor elements for electronic components according to the invention. In addition, the stability of inventive third layers to blue or ultraviolet light is particularly suitable when using LEDs, in particular white LEDs as semiconductor elements.

Furthermore, it can be provided that a heat sink is arranged on the second layer, preferably a metallic heat sink, particularly preferably an aluminum substrate.

The use of metallic heat sinks is precisely the purpose of substrates according to the invention, therefore, the connection with such a heat sink is a particularly preferred subject of the invention.

According to a further embodiment of the invention it can be provided that the first layer is connected to a metallization of a printed circuit board on a dielectric and preferably the second layer is connected in a recess of the dielectric with an underlying metallic substrate.

This corresponds to the desired and particularly suitable installation situation for a substrate according to the invention and is therefore claimed here particularly preferably with the invention.

The object of the invention is also achieved by a method for producing a substrate according to the invention, wherein on a first electrically conductive layer a third electrically insulating layer by sputtering, vapor deposition, physical vapor deposition (PVD), chemical vapor deposition (CVD), laminating, gluing, soldering or a printing method, in particular a screen printing method, is applied and that a second heat-conducting layer by PVD, sputtering, lamination, gluing, soldering, low-temperature silver sintering or a printing method, in particular a screen printing method, is applied to the third layer such that the second layer with the first layer has no electrical contact.

It can be provided that at least one recess is produced in the first layer, preferably by embossing, profile rolling or milling, wherein the third layer is applied to the first layer in the region of the depression.

These methods provide suitable substrates to solve the problem. Particularly easy embossing of the first layer is mechanically feasible.

The invention is based on the surprising finding that it is possible by the use of a thin film or a glass ceramic as an insulating layer to provide a homogeneous electrically insulating separation layer, which allows a uniform heat conduction into the second layer and thus allows a uniform and efficient cooling of the electronic element , When using a composite material such as that proposed in the prior art, thermal conduction causes scattering of the lattice vibrations (phonons) at the interfaces of the various materials of the composite. The use of thin layers or glass ceramics according to the invention provides a homogeneous third layer, through which the lattice vibrations or the phonons can propagate without scattering at interfaces within the electrical insulator. As a result, the thermal resistance of the insulator is reduced. The reduction of the Thermal resistance leads to greater cooling of the built-in substrate electronic element. As a result, elements with a larger electrical power can be installed in a smaller space.

Furthermore, the invention is based on the surprising finding that, when using a polymer matrix with ceramic powder as the third layer, a lower temperature can be selected in the construction of the third layer than in the production of a ceramic matrix from a preceramic material. As a result, the production of the substrate can be carried out at lower temperatures, which brings advantages with respect to the devices for machining the substrate. In particular, the production rate in mass production is significantly increased. The substrate is exposed to a lower thermal stress, whereby the third layer can be thinner and the durability of the substrate is improved or the rejects during production is reduced.

The thinner such a third layer according to the invention, the lower its thermal resistance and the greater the cooling power can be achieved by such a third layer. A thin-film technique requires the use of a homogeneous material, since the structure of a matrix requires a certain volume and thus a minimum thickness of at least 10 μm, usually well above 10 μm. Therefore, the use of a thin film was surprising. Since the thermal resistance of such a layer is also determined by its thickness, the reduction of the layer thickness per se already leads to an improvement of the prior art according to the invention.

The homogeneity of the glass ceramic layer is particularly high when the glass ceramic is melted or slightly melted during the firing on the first layer. By the melting process a uniform flat layer thickness is achieved and thus a uniform heat dissipation from the element. A further advantage of a glass-ceramic layer according to the invention and also of certain thin layers, for example of AlN, can be seen in its light stability. By contrast, various materials, such as the organic materials used in the prior art, are not stable to light in the visible blue spectrum and in the ultraviolet (UV) range. This limits the use in daylight and makes the use of the substrate in the use of LEDs as elements, in particular white LEDs impossible or at least leads to the fact that the use of such substrates draws considerable disadvantages. The blue and the UV light lead to embrittlement or discoloration of the third layer. This can lead to a deterioration of the thermal conductivity of the third layer and the transitions into the third and second layer and thus lead to a deterioration of the cooling capacity for the element, in particular for an LED. The substrates according to the invention are thus particularly suitable for use with LEDs as elements.

Due to the improved possibility for cooling the electronic elements or for heat removal from the elements, a higher packing density of the elements can be realized. For the example of an LED spotlight then a higher LED packing density can be produced.

In particular, however, the glass-ceramic layer also causes a corrosion protection for the surfaces of the first and / or second layer. This is especially true when the third layer is briefly melted or slightly melted, as then can create a particularly dense connection without inclusions.

Another advantage of substrates according to the invention is the low material costs, as the costs can be reduced by the small amount of expensive materials such as AlN. The modules / components produced can be separated more easily from a manufactured carrier tape. The lifetime of the manufactured components is improved by a better balance of the thermal expansion coefficients of the layers.

Exemplary embodiments of the invention are explained below with reference to six schematically illustrated figures, without, however, limiting the invention. Showing:

1 a schematic cross-sectional view of a first device according to the invention with a first substrate according to the invention;

2 a schematic cross-sectional view of a second device according to the invention with a second inventive substrate;

3 a schematic cross-sectional view of a third device according to the invention with a third inventive substrate;

4 a schematic cross-sectional view of a fourth device according to the invention with a substrate according to the invention, connected to a printed circuit board;

5 a perspective true-to-scale view of a device according to the invention on a substrate according to the invention; and

6 a perspective view of a device according to the invention on another substrate according to the invention.

1 shows a schematic cross-sectional view of an electronic component according to the invention 1 with a substrate according to the invention. The substrate comprises a first layer 2 from a base metal foil, a second layer 3 which is a metallization and one between the first layer 2 and the second layer 3 arranged third layer 4 from a dielectric. In the first shift 2 is a recess 5 for electrically separating two regions of the first layer 2 intended. Finally, the substrate also comprises a carrier foil 6 made of plastic.

In the carrier film 6 is a first recess 7 provided in which a semiconductor element 8th with a lot 9 , a conductive adhesive 9 or one of a silver sintered compound 9 with a first region of the first layer 2 the substrate is contacted. A second recess 7 that over another, from the first area of the first layer 2 electrically separated second region of the first layer 2 is arranged, serves to an upper contact zone of the semiconductor element 8th with the help of a bond wire 10 with this second area of the first layer 2 to contact.

Over the two areas of the first layer 2 electrically through the recess 5 are separated from each other, the semiconductor element 8th be powered by applying a voltage. The case in the semiconductor element 8th consumed electrical power is converted to a large extent in heat energy. Thus, the performance of the semiconductor element 8th is preserved and the semiconductor element 8th is not destroyed or can work under uniform conditions, it is necessary to heat from the semiconductor element 8th dissipate.

Through from the first area of the first layer 2 through the dielectric of the third layer 4 separate second layer 3 , is a metallic, so good thermal conductivity electrically neutral area available over which the device 1 or the semiconductor element 8th is coolable. The thin dielectric layer 4 causes only a small heat resistance in the transition from the first metallic layer 2 on the second metallic layer 3 ,

2 shows a schematic view of a second electronic component according to the invention 11 with one compared to the one in 1 shown only slightly modified construction. The modification relates to the substrate according to the invention, more precisely the first layer 2 of the substrate. In this first shift 2 , which consists for example of an aluminum alloy, is a depression 12 provided the second layer 3 , which consists for example of a glass ceramic, and the third layer 4 , which consists for example of aluminum, absorbs. The depression 12 is made by embossing, roll forming and / or milling in the first layer 2 generated. The first layer is with a carrier foil 6 made of plastic laminated. Subsequently, the third layer 4 by gluing and then the second layer 3 applied by soldering. Afterwards or before the recess becomes 5 in the first shift 2 generates and thus two mutually electrically isolated areas of the first layer 2 educated.

The lamination of the plastic carrier film 6 with the first layer 2 , the generation of the recesses 7 in the plastic carrier film 6 and the preparation of the recess 12 in the first shift 2 can be done in one step by a punch-laminating technique.

The substrate thus prepared may be heated in a further step to achieve uniform bonding of the glass-ceramic 4 with the metal layers 2 . 3 to create. If the temperature is too high for the plastic carrier film 6 is, it is expedient, this only after this temperature treatment on the first metal layer 2 apply.

In the finished substrate may then be a semiconductor element 8th , such as an LED, in one of the recesses 7 in the plastic carrier film 6 with a lot 9 be soldered. This is the bottom of the semiconductor element 8th with the first region of the first metal layer 2 contacted. The top of the semiconductor element 8th is via a bonding wire 10 with the second region of the first metal layer 2 contacted.

Through the depression 12 has the substrate or the component 11 a bottom that lies at a height or in a plane. As a result, the substrate can also be connected to the semiconductor element 8th easily applied to flat boards or printed circuit boards. The two areas of the first layer 2 form the electrodes of the electronic component 11 , The second layer 3 forms an electrically neutral region directly below the semiconductor element 8th is arranged and over which the heat from the semiconductor element 8th can be dissipated.

3 shows a schematic view of a third electronic component according to the invention 21 with one compared to 2 changed construction. A first shift 2 is here through recesses 5 divided into three areas that are electrically isolated from each other.

The two outer areas of the first layer 2 could also be connected electronically. This would be a single recess 5 suitable if in the third dimension (in the image depth of the 3 ) is shaped accordingly.

The middle area of the first layer 2 is thinner than the two outer areas. In the middle area of the first layer 2 are on the bottom of the third layer 4 and below that the second layer 3 arranged. The thickness of the second and third layers 3 . 4 along with the first layer 2 in the middle area is the same size as the thickness of the first layer 2 in the outer areas.

The third layer 4 For example, in the present case, it may be a polymer matrix such as an epoxy resin in which a ceramic powder such as aluminum nitride (AlN) is embedded. The grain size of the ceramic powder according to the invention can be between 0.1 μm and 10 μm, preferably between 0.5 μm and 5 μm. The third layer 4 gets on the first layer 2 applied by a printing process.

On the top of the first layer 2 is a carrier foil 6 arranged the areas of the first layer 2 connects together and the entire substrate structure along with the first layer 2 wearing. In the carrier film 6 are recesses 7 intended. In the middle recess 7 is an electronic element 8th , such as a semiconductor transistor. The electronic element 8th is at its bottom on the middle area of the first layer 2 with a lot 9 soldered. On the top of the electronic element 8th this is with two bond wires 10 with the two outer regions of the first layer 2 connected. The bonding wires are sufficient for this purpose 10 through the outer recesses 7 in the carrier film 6 ,

4 shows in a schematic cross-sectional view of a device according to the invention, as shown 1 which is built on a circuit board. The electronic component according to 4 is with his first shift 2 outside over a lot 33 with tracks 34 that is with the metallizations 34 connected to a printed circuit board. The metallizations 34 are on a dielectric 35 arranged on the top of the circuit board.

The inside of the circuit board is a metallic heat sink 36 , which consists for example of copper or aluminum. The underside of the circuit board is also covered by a dielectric 35 covered. In the upper dielectric 35 a recess is provided through which the second layer 3 with the heat sink 36 connected is. These are the second layer 3 and the heat sink 36 with each other with a lot 33 soldered.

The arrows in 4 show the heat flow from an electronic element 8th of the electronic component, for example of a high power LED, by a conductive adhesive 9 , through the first layer 2 , the third layer 4 , the second layer 3 and the metallic solder 33 in the heat sink 36 where the heat is dissipated to all sides. The heat sink 36 is generally made substantially thicker than the component, or the first layer 2 , 4 is therefore not to be regarded as a true to scale drawing.

5 shows a perspective to scale view of a device according to the invention 41 on a substrate according to the invention. The substrate comprises a metallic first layer 42 . 42 ' on its underside in a recess 52 a second metallic layer 43 is arranged through a dielectric thin film 44 from the first metallic layer 42 . 42 is electrically isolated. The first shift 42 . 42 ' is through a recess 45 in a first area 42 and a second area 42 ' separated. The two areas 42 . 42 ' are electrically isolated from each other.

On the top of the first layer 42 . 42 ' is a carrier foil 46 glued from PET. Through a larger recess in the carrier film 46 a thickening of the first layer is sufficient 42 in the first area 42 , Over the second area 42 ' is another recess 47 in the carrier film 46 intended. On the thickening of the first layer 42 . 42 ' in the first area 42 is an electronic element 48 arranged that large area electrically and thermally conductive with the first area 42 the first layer 42 . 42 ' connected is. On the top of the electronic element 48 there is a contact 57 about which the electronic element 48 can be supplied with electrical energy.

A bonding wire 50 connects the contact 57 with the second area 42 ' the first layer 42 . 42 ' , So if a tension between the two areas 42 . 42 ' is created, becomes the electronic element 48 supplied with electrical energy. The electronic element 48 converts the electrical energy, for example, by generating light, which also generates heat. So that the electronic element 48 Non-destructive and can work under uniform conditions, it is necessary to dissipate the resulting heat energy. This may be the component 41 be mounted on a printed circuit board (not shown), which in addition to the two metallic terminals (metallizations) for power supply also includes a metallic cooling connection, which is electrically isolated from the current-carrying parts. The live conductor tracks are connected to the two areas 42 . 42 ' the first metallic layer 42 . 42 contacted, while the cooling connection with the second metallic layer 43 is connected. The latter compound should be large and continuous, to good heat conduction between the second metallic layer 43 and to reach the heat sink. A good connection can be achieved for example by soldering, welding or cold welding.

The heat from the electronic element 48 then flows through the first area 42 the first layer 42 . 42 ' , through the dielectric thin film 44 and the second metallic layer 43 into the cooling connection of the circuit board, where the heat is dissipated.

6 shows a perspective view of a device according to the invention on a further inventive substrate. The substrate comprises an embossed first layer 42 42 ' made of aluminium. On the underside of a part of the first layer projecting downwards through the embossing 42 is a thin, insulating AlN layer 44 evaporated on which a thin metallic layer 43 was evaporated. The vapor deposition can be carried out by a PVD process such as sputtering or a CVD process. In the first shift 42 . 42 ' are recesses 45 provided the first layer 42 . 42 ' in a first area 42 and a second area 42 ' subdivide, which are electrically isolated from each other. The recesses may also be filled with an electrically insulating material to increase the stability of the substrate.

The substrate also comprises a carrier foil 46 , which are in the range of the expression of the first layer 42 or the second metallic thin film 43 has a recess through which the expression with the AlN layer 44 and the metallic thin film 43 passes through. The material of the metallic thin film 43 can be matched to the material of the heat sink (not shown), which is used for cooling the device shown.

On the top of the first layer 42 . 42 ' is in the depression by the expression of an electronic element 48 , soldered like a chip or an LED. On the top of the electronic element 48 is a contact 57 provided with the help of a ribbon wire 50 the top of the electronic element 48 with the second area 42 the first layer 42 . 42 ' combines. To the right and left of the section shown 6 the structure of the substrate continues, thereby creating a variety of electronic elements 48 is connected in series.

The series connection of the electronic elements 48 only succeeds if they can be effectively cooled, as in the present case by the electrically neutral connection with the metallic thin film 43 is possible.

The first layers shown 2 . 42 . 42 ' can be made with a stamped-circuit-board technology (SCB technology). On top of or below these is then additionally a dielectric 4 . 44 applied to the turn a conductive layer (metallization) 3 . 43 for further contact on a heat sink 36 or on a metal core board 34 . 35 . 36 is applied.

The features of the invention disclosed in the foregoing description, as well as the claims, figures and embodiments may be essential both individually and in any combination for the realization of the invention in its various embodiments.

LIST OF REFERENCE NUMBERS

1, 11, 21, 41

module

2, 42, 42 '

first shift

3, 43

second layer

4, 44

third layer

5, 45

Recess in the first layer

6, 46

support film

7

Recess in the carrier film

8, 48

Semiconductor element

9, 33

Lot / Conductive glue / silver sintered joint

10, 50

bonding wire

12, 52

Deepening in the first layer

34

Metallization of a printed circuit board

35

Dielectric of a printed circuit board

36

Heat sink / heat sink

57

Contact

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 19625622 A1 [0004]
• DE 102009000882 A1 [0006]

Claims (24)

Substrate for receiving at least one electronic element ( 8th . 48 ), in particular at least one semiconductor element ( 8th . 48 ), comprising an electrically conductive first layer ( 2 . 42 . 42 ' ) for contacting the element ( 8th . 48 ), a thermally conductive second layer ( 3 . 43 ) for removing heat from the element ( 8th . 48 ) and an electrically insulating third layer ( 4 . 44 ) between the first layer ( 2 . 42 . 42 ' ) and the second layer ( 3 . 43 ), so that the third layer ( 4 . 44 ) the first layer ( 2 . 42 . 42 ' ) of the second layer ( 3 . 43 ) electrically isolated, wherein the third layer ( 4 . 44 ) is a thin film. Substrate according to claim 1, characterized in that the thickness of the third layer ( 4 . 44 ) is less than 10 microns, preferably less than 5 microns, more preferably less than 2 microns. Substrate according to claim 1 or 2, characterized in that the third layer ( 4 . 44 ) by sputtering, vapor deposition, physical vapor deposition (PVD) or chemical vapor deposition (CVD) on the first layer ( 2 . 42 . 42 ' ) is applied. Substrate according to one of the preceding claims, characterized in that the third layer ( 4 . 44 ) consists of AlN or Al ₂ O ₃ . Substrate for receiving at least one electronic element ( 8th . 48 ), in particular at least one semiconductor element ( 8th . 48 ), comprising an electrically conductive first layer ( 2 . 42 . 42 ' ) for contacting the element ( 8th . 48 ), a thermally conductive second layer ( 3 . 43 ) for removing heat from the element ( 8th . 48 ) and an electrically insulating third layer ( 4 . 44 ) between the first layer ( 2 . 42 . 42 ' ) and the second layer ( 3 . 43 ), so that the third layer ( 4 . 44 ) the first layer ( 2 . 42 . 42 ' ) of the second layer ( 3 . 43 ) electrically isolated, wherein the third layer ( 4 . 44 ) is a glass ceramic. Substrate according to claim 5, characterized in that the third layer ( 4 . 44 ) by a printing process, in particular by a screen printing process, on the first layer ( 2 . 42 . 42 ' ) and baked in the substrate, preferably on the first layer ( 2 . 42 . 42 ' ) is melted. Substrate for receiving at least one electronic element ( 8th . 48 ), in particular at least one semiconductor element ( 8th . 48 ), comprising an electrically conductive first layer ( 2 . 42 . 42 ' ) for contacting the element ( 8th . 48 ), a thermally conductive second layer ( 3 . 43 ) for removing heat from the element ( 8th . 48 ) and an electrically insulating third layer ( 4 . 44 ) between the first layer ( 2 . 42 . 42 ' ) and the second layer ( 3 . 43 ), so that the third layer ( 4 . 44 ) the first layer ( 2 . 42 . 42 ' ) of the second layer ( 3 . 43 ) electrically isolated, wherein the third layer ( 4 . 44 ) is a filled with ceramic powder polymer matrix. Substrate according to claim 7, characterized in that the polymer of the polymer matrix is a silicone or a resin, preferably an epoxy resin, acrylic resin, silicone resin, particularly preferably Silikoftal ^® or a silicone-polyester resin and / or the ceramic powder is an Al ₂ O ₃ powder, an AlN powder and / or a BN powder. Substrate according to claim 7 or 8, characterized in that in the polymer matrix, a plurality of spacers are provided, so that the third layer has a defined and uniform thickness, which is predetermined by the thickness of the spacer, wherein the spacers are in particular spherical and preferably glass, SiO ₂ glass, Al ₂ O ₃ , AlN and / or SiN. Substrate according to one of the preceding claims, characterized in that the second layer ( 3 . 43 ) is metallic or comprises a metal core. Substrate according to one of the preceding claims, characterized in that the third layer ( 4 . 44 ) and the second layer ( 3 . 43 ) in a depression ( 12 . 52 ) of the first layer ( 2 . 42 . 42 ' ) and the third layer ( 4 . 44 ) the first layer ( 2 . 42 . 42 ' ) and the second layer ( 3 . 43 ) the third layer ( 4 . 44 ) in the depression ( 12 . 52 ) at least partially covered, wherein preferably the thickness of the third layer ( 4 . 44 ) and second layer ( 3 . 43 ) together the depth of the depression ( 12 . 52 ), so that the surface of the second layer ( 3 . 43 ) in a, in particular, plan level with the first layer ( 2 . 42 . 42 ' ) outside the depression ( 12 . 52 ) lies. Substrate according to one of the preceding claims, characterized in that the second layer ( 3 . 43 ) by PVD, sputtering, laminating, gluing, soldering, low-temperature silver sintering or a printing process, in particular a screen printing process, with the third layer ( 4 . 44 ) connected is. Substrate according to one of the preceding claims, characterized in that the third layer ( 4 . 44 ) the first layer ( 2 . 42 . 42 ' ) only partially covers and / or the second layer ( 3 . 43 ) the third layer ( 4 . 44 ) only partially covers. Substrate according to one of the preceding claims, characterized in that the first layer ( 2 . 42 . 42 ' ) in two electrically isolated areas ( 42 . 42 ' ), in particular by a recess ( 5 . 45 ), so the element ( 8th . 48 ) with the two areas ( 42 . 42 ' ) is contactable, preferably an electrical voltage on the element ( 8th . 48 ) about the areas ( 42 . 42 ' ) can be applied. Substrate according to one of the preceding claims, characterized in that the third layer ( 4 . 44 ) has a thermal conductivity of more than 5 W / m K, preferably of more than 30 W / m K, more preferably of more than 100 W / m K. Substrate according to one of the preceding claims, characterized in that the third layer ( 4 . 44 ) is homogeneous, in particular consists of only one solid material. Substrate according to one of the preceding claims, characterized in that on the first layer ( 2 . 42 . 42 ' ), preferably on the third layer ( 4 . 44 ) opposite side, a carrier film ( 6 . 46 ), in particular a plastic film is arranged, the preferred openings ( 7 ) for each element ( 8th . 48 ) and preferably for each element ( 8th . 48 ) one or two additional openings ( 7 ), in particular in another field ( 42 ' ) of the first layer ( 2 . 42 . 42 ' ) than that of the element ( 8th . 48 ), in a partially divided first layer ( 2 . 42 . 42 ' ). Electronic component ( 1 . 11 . 21 . 41 ), in particular semiconductor component ( 1 . 11 . 21 . 41 ), comprising at least one semiconductor element ( 8th . 48 ) and a substrate according to one of the preceding claims, wherein the semiconductor element ( 8th . 48 ) on a first side flat with the first layer ( 2 . 42 . 42 ' ) is electrically conductively connected, preferably via a solder ( 9 ), a conductive adhesive ( 9 ) or a silver sintered compound ( 9 ). Component ( 1 . 11 ; 21 . 41 ) according to claim 18, characterized in that the at least one semiconductor element ( 8th . 48 ) on a second side via a bonding wire ( 10 . 50 ) with the first layer ( 2 . 42 . 42 ' ) is contacted, so that an electrical voltage between the first and second sides of the semiconductor element ( 8th . 48 ) can be applied, wherein the first layer ( 2 . 42 . 42 ' ) into at least two areas ( 42 . 42 ' ) and the two sides of the semiconductor element ( 8th . 48 ) with different areas ( 42 . 42 ' ) of the first layer ( 2 . 42 . 42 ' ) are connected. Component ( 1 . 11 . 21 . 41 ) according to claim 18 or 19, characterized in that the at least one semiconductor element ( 8th . 48 ) is a chip or an LED. Component ( 1 . 11 . 21 . 41 ) according to one of claims 18 to 20, characterized in that at the second layer ( 3 . 43 ) a heat sink ( 36 ) is arranged, preferably a metallic heat sink ( 36 ), particularly preferably an aluminum substrate. Component ( 1 . 11 . 21 . 41 ) according to one of claims 18 to 21, characterized in that the first layer ( 2 . 42 . 42 ' ) with a metallization ( 34 ) of a printed circuit board on a dielectric ( 35 ) and preferably the second layer ( 3 . 43 ) in a recess of the dielectric ( 35 ) with a metallic substrate ( 36 ) connected is. Process for producing a substrate according to one of Claims 1 to 17, characterized in that a third electrically insulating layer is applied to a first electrically conductive layer by sputtering, vapor deposition, physical vapor deposition (PVD), chemical vapor deposition (CVD), lamination, gluing, soldering or a printing method, in particular a screen printing method, is applied and that a second heat-conducting layer by PVD, sputtering, lamination, gluing, soldering, low-temperature silver sintering or a printing method, in particular a screen printing method, is applied to the third layer such that the second layer with the first layer has no electrical contact. A method according to claim 23, characterized in that in the first layer at least one recess is produced, preferably by embossing, roll forming or milling, wherein the third layer is applied in the region of the depression on the first layer.

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