Multilayer component and method for producing a multilayer component

Abstract

Multilayer component (100) comprising an inert ceramic substrate (1) and at least one functional ceramic (2), wherein the functional ceramic (2) is completely enclosed by the ceramic substrate (1), wherein the functional ceramic (2) comprises a varistor, an NTC ceramic, a PTC ceramic or a ferrite, wherein the multilayer component (100) comprises a plurality of functional ceramics (2), and wherein the functional ceramics (2) have different expansion coefficients and / or different sintering temperatures.

Description

[0001] The present invention relates to a ceramic multilayer component. The invention further relates to a method for producing a ceramic multilayer component.

[0002] For the integration of functionalities into multilayer components, the integration of a fully enclosed electroceramic or functional ceramic into an inert organic material is known. The construction of a carrier from a functional ceramic itself, such as a varistor ceramic, is also known. However, additional surface layers, such as glass or polymer, are required to protect the functional ceramic from external influences.

[0003] Multilayer components with functional ceramics are widely used in the prior art. Examples can be found, for example, in publications US 9 036 317 B2, JP 5 796 677 B2, US 2012 / 0 299 693 A1, US 2009 / 0 067 113 A1, US 6 608 547 B1, and US 2011 / 0 222 197 A1. Examples in which ceramic substrate layers enclose functional ceramics, such as a varistor or a ferrite, are known, for example, from publications US 5 661 882 A and JP 2007 - 053 328 A.

[0004] One problem to be solved is to provide an improved multilayer component and a method for producing an improved multilayer component.

[0005] This object is achieved by the subject matter and the method according to the independent claims.

[0006] Further features of the invention are defined by the further claims.

[0007] According to one aspect, a multilayer component is specified. The multilayer component has an inert ceramic substrate. "Inert" in this context means that a surface of the ceramic substrate has a high insulation resistance. The high insulation resistance protects the surface of the substrate against external influences. The high insulation resistance makes the surface insensitive to electrochemical processes, such as the deposition of metallic layers on the surface. The high insulation resistance also makes the surface of the substrate insensitive to aggressive media, e.g., aggressive fluxes used, for example, in soldering processes.

[0008] The multilayer component comprises at least one functional ceramic. The multilayer component according to the invention comprises more than one functional ceramic. For example, the multilayer component comprises two, three, five, ten, or more functional ceramics. The functional ceramic serves to provide specific functionalities of the multilayer component. The functional ceramic serves to integrate the specific functions into the substrate. Different functional ceramics can provide different but also identical functionalities.

[0009] The ceramic substrate serves as a carrier for the functional ceramic. The functional ceramic is completely enclosed by the ceramic substrate. In other words, the functional ceramic is surrounded on all sides by the inert, dielectric ceramic material of the substrate. The functional ceramic has specific properties, such as a defined shape and size, to integrate the functional ceramic into the ceramic substrate. For example, the functional ceramic is grain-shaped, spherical, disc-shaped, elliptical, or cubic. For example, the functional ceramic has a diameter of less than or equal to 100 µm, for example, 50 µm.

[0010] The ceramic substrate has specific properties for integrating the functional ceramic into the substrate. For example, a recess is provided in an inner region of the substrate into which the functional ceramic is inserted during the production of the multilayer component. The functional ceramic is arranged entirely within the interior of the substrate.

[0011] The inert, dielectric, ceramic substrate protects the functional ceramic from harmful external influences. This allows for a compact, stable, durable, and adaptive multilayer component.

[0012] According to one embodiment, the ceramic substrate comprises LTCC (low-temperature cofired ceramics). LTCC technology allows the realization of ceramic multilayer components with multiple metallization levels, into which a multitude of passive components such as conductor tracks, resistors, capacitors, and inductors can be integrated. The LTCC ceramic preferably has a low dielectric constant. This allows unwanted parasitic electrical effects, such as parasitic capacitances of the substrate, to be suppressed.

[0013] According to the invention, the multilayer component comprises a plurality of functional ceramics. The functional ceramics have different properties. The functional ceramics exhibit different expansion coefficients and / or different sintering temperatures. By completely embedding the functional ceramics in the inert dielectric ceramic material of the substrate, the different properties of the functional ceramics can be compensated. A wide variety of functionalities can thus be integrated. This allows for the realization of extremely adaptive and flexibly deployable multilayer components.

[0014] According to one embodiment, the at least one functional ceramic comprises an HTCC ceramic. Sintering temperatures for HTCC ceramics are significantly above 1000°C, for example, 1500°C. The grain structure of the HTCC ceramic is not affected by the processing (firing) of the LTCC ceramic of the substrate at temperatures significantly below 1000°C. The functionality of the functional ceramic in the substrate is thus retained even after the LTCC ceramic is fired.

[0015] According to the invention, the functional ceramic comprises a varistor, an NTC (negative temperature coefficient) ceramic, a PTC (positive temperature coefficient) ceramic, or a ferrite. For example, the functional ceramic is designed as an ESD protection element. The functional ceramic can thus provide various functionalities of the multilayer component.

[0016] According to a further aspect, a method for producing a multilayer component is described. The method preferably produces the multilayer component described above. All features described in connection with the multilayer component also apply to the method, and vice versa.

[0017] In a first step, at least one functional ceramic, preferably several functional ceramics, are produced. Functional ceramics with different functionalities can be produced. The respective functional ceramic is based on ceramic spray granules, a ceramic powder, and / or ceramic green layers. The spray granules, the ceramic powder, and / or the green layers are sieved, pressed, and sintered. During this manufacturing process, the functional ceramic is sintered at temperatures greater than or equal to 1000°C, for example, 1300°C or 1500°C. During production, the functional ceramic can be given a wide variety of geometric shapes. For example, the functional ceramic can have a sintered grain, a sintered sphere, a sintered chip, or a sintered cube.

[0018] In a further step, LTCC green sheets are prepared, each having at least one recess. The green layers are stacked on top of each other. The recess is created by punching or lasering the green sheets and completely penetrates the provided green sheets.

[0019] In a further step, electrode structures are provided, for example, printed, on at least a portion of the green sheets. The electrode structures comprise, for example, silver and / or palladium. The electrode structures are preferably applied before the prepared green sheets are stacked.

[0020] In a next step, the functional ceramic is inserted into the recess. Specifically, the recess is filled with the functional ceramic and then vibrated into the recess to ensure a precise fit.

[0021] In a further step, ceramic cover sheets are prepared in the green state. These are placed on the top and bottom of the stack of green sheets. The cover sheets are free of the recess, so that the functional ceramic is surrounded by ceramic material on all sides.

[0022] In a further step, the green films and the cover films are laminated and pressed into a green stack.

[0023] In a further step, additional recesses can optionally be introduced into the green stack using punching or laser processes to create through-holes.

[0024] These recesses completely penetrate the green stack. The recesses are located in an area of the green stack that is spatially separated from the area in which the functional ceramic is located.

[0025] In a further step, the green stack is sintered. The green stack is sintered at a temperature that is, for example, 150 °C below the sintering temperature of the functional ceramic. This ensures that the functionality of the integrated functional ceramic is not affected by the sintering of the green stack. By appropriately selecting the LTCC ceramic with defined sintering shrinkage in the z-direction and low shrinkage in the x- and y-directions, the functional ceramic is enclosed by the ceramic substrate without cracks. The ceramic material of the substrate can fit snugly against the functional ceramic. Alternatively, a gap can remain between the functional ceramic and the material of the ceramic substrate after sintering the green stack.

[0026] In a final step, external contacts are provided on the outer surfaces of the sintered green stack. For example, a silver paste is applied to the front side of the sintered green stack and then fired.

[0027] The resulting multilayer component has at least one functional ceramic fully integrated into the ceramic substrate. By embedding the functional ceramic in the inert, dielectric ceramic material, the multilayer component can be exposed to harsh environmental conditions (high temperatures, aggressive media) without damage to the functional ceramic. Due to the low dielectric constant of the ceramic substrate, the multilayer component can also be used in applications where the reduction of unwanted parasitic electrical effects (e.g., parasitic capacitance) of the substrate plays a role. This provides a long-lasting and adaptive multilayer component.

[0028] The drawings described below are not to be considered to scale. Rather, individual dimensions may be enlarged, reduced, or distorted for clarity.

[0029] Elements that are identical or that perform the same function are designated by the same reference symbols.

[0030] Some of the figures show only one functional ceramic for illustrative purposes. However, according to the invention, a plurality of functional ceramics is always provided in a multilayer component.

[0031] They show: Fig. 1 a schematic representation of a multilayer component, Fig. 2 a sectional view of a multilayer component according to a first embodiment, Fig. 3 a sectional view of a multilayer component according to a second embodiment, Fig. 4 a horizontal sectional view of the multilayer component according to Fig. 3, Fig. 5 a horizontal sectional view of the multilayer component according to Fig. 3 according to a further embodiment, Fig. 6 a sectional view of a multilayer component according to a third embodiment, Fig. 7 a sectional view of a multilayer component according to a fourth embodiment, Fig. 8a shows a process step in the production of a multilayer component according to the invention, Fig. 8b shows a further process step in the production of a multilayer component according to the invention, Fig. 8c shows a further process step in the production of a multilayer component according to the invention, Fig. 8d shows a further process step in the production of a multilayer component according to the invention.

[0032] The Fig. 1 shows a schematic representation of a multilayer component 100. The multilayer component 100 has a substrate 1. The substrate 1 preferably has an inert dielectric ceramic carrier. In this context, "inert" means that a surface of the substrate 1 has a high insulation resistance. The high insulation resistance makes the surface of the substrate 1 insensitive to electrochemical processes, such as the deposition of metallic layers, e.g., layers comprising Ni, Z, Ag, or Ad, on the surface of the substrate 1. The high insulation resistance also makes the surface of the substrate 1 insensitive to aggressive media, such as aggressive fluxes used, for example, in soldering processes. These aggressive media can attack the surface and lead to undesirable side effects, such as short circuits and leakage currents.

[0033] The substrate 1 is preferably a multilayer ceramic. The substrate 1 preferably comprises an LTCC ceramic. Particularly preferably, the substrate 1 comprises a glass ceramic.

[0034] The multilayer component 100 further comprises a plurality of functional ceramics 2, for example, two, three, five, or ten functional ceramics 2. The functional ceramics 2 are arranged within the substrate 1. The functional ceramics 2 are completely enclosed by the substrate 1. The functional ceramics 2 are spatially separated from one another and electrically insulated.

[0035] The respective functional ceramic 2 preferably comprises an HTCC ceramic. The respective functional ceramic 2 can comprise ZnO-Pr (varistor), MnNiX (NTC ceramic), BaTiO3 (PTC ceramic), or a ferrite, depending on the desired function and mode of operation of the respective functional ceramic 2. In non-inventive examples, multiple functional ceramics 2 can also have the same composition. According to the invention, each functional ceramic 2 is designed differently to realize various desired functions within the substrate 1.

[0036] The inert surface of the substrate 1 protects the functional ceramics 2 from external influences. Additional surface protection layers for the functional ceramics, such as glass or polymer layers, are therefore unnecessary.

[0037] The Fig. 2 shows a sectional view of a multilayer component 100 according to a first embodiment. In particular, Fig. 2 shows a multilayer component 100 with a ceramic substrate 1 and an integrated disc varistor as functional ceramic 2. The functional ceramic 2 preferably comprises a plastic-molded varistor, such as an SMD CU varistor or a ThermoFuse varistor.

[0038] The functional ceramic 2 is disk-shaped. The functional ceramic 2 preferably comprises a metal disk. The functional ceramic is a disk varistor. For example, the functional ceramic comprises ZnO-Pr.

[0039] The substrate 1 has internal electrodes 4. The internal electrodes 4 are arranged between ceramic layers (not explicitly shown) of the substrate 1. The internal electrodes 4 serve to electrically contact the functional ceramic 2. The functional ceramic 2 is arranged in a recess 6 (not explicitly shown here) in the interior of the substrate 1. The internal electrodes 4 extend to the edge of this recess 6 in order to electrically contact the functional ceramic 2.

[0040] The functional ceramic 2 has external contacts 3. The external contacts 3 are formed on outer surfaces, here the top and bottom, of the functional ceramic 2. For example, the external contacts 3 are metal layers on the top and bottom of the functional ceramic 2. The internal electrodes 4 are electrically connected to the external contacts 3.

[0041] Furthermore, external electrodes 5 are arranged on the opposite side surfaces of the substrate 1 for electrically contacting the multilayer component 100. The external electrodes 5 are alternately electrically connected to internal electrodes 4 of different polarity.

[0042] The Fig. The multilayer component 100 shown in Figure 2 is designed for high-temperature applications at temperatures ≥ 150°C. The substrate 1, which completely surrounds the functional ceramic 2, protects the functional ceramic 2 from the high temperatures encountered. In particular, the inert surface of the substrate 1 serves to protect the integrated disc varistor, which is specified for maximum operating temperatures of up to 85°C, from the high temperatures.

[0043] The Fig. 3 shows a sectional view of a multilayer component 100 according to a second embodiment. In particular, Fig. 3 shows a multilayer component 100 with an integrated SMD (surface-mounted device) varistor with a low clamping voltage and capacitance as a functional ceramic 2. The clamping voltage occurs during an ESD event along with a specific surge current at the component. The higher the clamping voltage occurring at the varistor at the same current, the greater the electrical power and thus ultimately the energy the varistor must absorb. At lower clamping voltages, a higher current carrying capacity is achieved to achieve the same energy absorption.

[0044] The multilayer component 100 has the substrate 1 described above. The functional ceramic 2 is arranged or embedded in a recess 6 within the substrate 1. The recess 6 enables the introduction of the functional ceramic 2 into the substrate 1 during the manufacturing process. For example, the recess 6 has a sintered via or a sintered through-plating of individual layers of the substrate 1. The recess 6 is characterized in particular by the fact that it does not completely penetrate the substrate 1. Thus, the functional ceramic 2 embedded in the recess 6 is surrounded on all sides, i.e. completely, by the material of the substrate 1.

[0045] Depending on the requirements of the multilayer component 100, the recess 6 and / or the functional ceramic 2 can be designed such that the functional ceramic 2 is enclosed by the substrate 1 in such a way that no gap remains between the material of the substrate 1 and the functional ceramic 2 (see Fig. 2). Alternatively, the recess 6 can also be designed in such a way that a gap remains between the functional ceramic 2 and the material of the substrate 1 (see Fig. 3), so that the recess 6 is visible even after completion of the multilayer component 100. This may be necessary, in particular, if the material of the functional ceramic 2 and the substrate 1 has different expansion coefficients, in order to avoid cracks or damage to the multilayer component 100 during further processing, for example, during soldering.

[0046] In this exemplary embodiment, the functional ceramic 2 is spherical. The functional ceramic 2 preferably comprises a varistor sphere. The functional ceramic 2 comprises, for example, ZnO-PrCo. The functional ceramic 2 is preferably a sintered ZnO-PrCo grain. The functional ceramic 2 has a low capacitance. For example, the capacitance of the functional ceramic is 0.5 pF or less, for example 0.47 pF. The functional ceramic 2 has a diameter of less than 100 µm, preferably less than or equal to 50 µm. The functional ceramic preferably has a specific electric field strength Ev = 500 V / mm. The dielectric constant epsilon of the functional ceramic 2 is high. For example, eps = 400.

[0047] In contrast, substrate 1 has a very low dielectric constant epsilon. For example, the dielectric constant of the substrate is less than 50, preferably less than 10. Preferably, epsilon = 7 or epsilon = 7.5. The low dielectric constant of the surrounding substrate 1 serves to suppress the parasitic capacitance of substrate 1. For example, the parasitic capacitance of substrate 1 is 0.47 pF lower than the parasitic capacitance of a standard carrier substrate with epsilon = 400 according to the prior art.

[0048] The substrate 1 further comprises the properties already described in connection with Fig. 2. Finally, the outer electrodes 5 are arranged on the opposite side surfaces of the substrate 1 for electrically contacting the multilayer component 100.

[0049] The internal electrodes 4 serve to electrically contact the functional ceramic 2 and extend to the edge of the recess 6 in order to electrically contact the functional ceramic 2. Depending on the design of the functional ceramic, the respective internal electrode 4 can have a different shape (see the Fig. 4 and Fig. 5). For example, the respective inner electrode 4 can have a constriction 4b in the area of the feed to the functional ceramic ( Fig. 5). This is particularly advantageous when the functional ceramic 2 is spherical. In particular, the respective inner electrode 4 can be electrically connected to the functional ceramic 2 in a targeted and precise manner by the constriction 4b. Alternatively, the respective inner electrode 4 can have a web 4a or web-shaped connection area for electrically contacting the functional ceramic 2 ( Fig. 4). This is advantageous, for example, when the functional ceramic 2 has a larger horizontal dimension, for example, an elliptical shape. However, other configurations of the inner electrode 4 for connecting the functional ceramic 2 are also conceivable.

[0050] The Fig. 6 shows a sectional view of a multilayer component 100 according to a third embodiment. In particular, Fig. 6 shows a multilayer component 100 in the form of an LED carrier with integrated ESD protection. In the following, only the differences to the Fig. 2 to 5 described multilayer components 100.

[0051] The multilayer component 100 has a heat source 10, for example, an LED. The heat source 10 is electrically connected to the external contacts 5 of the substrate 1 via contact surfaces 9 on the underside of the heat source 10, for example, an electrically conductive metallic layer. In this exemplary embodiment, the respective external contact 5 is arranged on the top side of the substrate 1 and connected to the respective contact surface 9 via a solder connection 8.

[0052] The substrate 1 has vias or through-contacts 7. Each through-contact 7 completely penetrates the substrate 1 in the vertical direction. On the top side of the substrate 1, each through-contact 7 is electrically connected to an external contact 5. Arranged on the underside of the substrate 1 are additional external electrodes 5, which are electrically connected to the respective through-contact 7. In this exemplary embodiment, the internal electrodes 4 do not extend to the side surfaces of the substrate 1, but are electrically connected to the through-contacts 7.

[0053] The substrate 1 can further comprise a thermal contact 11, for example, for a temperature sensor. The thermal contact 11 can, for example, comprise a metal-filled via.

[0054] The functional ceramic 2 is, for example, spherically shaped, sintered, and inserted into the recess 6 within the substrate 1, so that the functional ceramic 2 is completely surrounded on all sides by the material of the substrate 1. In this embodiment, the functional ceramic 2 serves as an ESD protection structure. The functional ceramic 2 is a varistor chip. The heat source 10, which is very sensitive to overvoltages, such as those triggered by an ESD pulse, is effectively protected against these current or voltage surges with the help of the functional ceramic 2.

[0055] The Fig. Figure 7 shows a sectional view of a multilayer component 100 according to a fourth embodiment. In particular, Fig. 7 shows a multilayer component 100 in the form of an LED carrier with integrated ESD protection and temperature sensor.

[0056] In the following, only the differences to the one related to Fig. 6 described multilayer component 100. In addition to the multilayer component 100 of Fig. 6, a second functional ceramic 2 is embedded in the substrate 1. The two functional ceramics 2 are spatially separated from each other and each completely surrounded by the material of the substrate 1.

[0057] A first functional ceramic 2, which is Fig. 7, shown in the lower area of the substrate 1, serves as an ESD structure and protects the heat source 10, for example, an LED, from overvoltages. The first functional ceramic 2 is designed as a varistor chip.

[0058] A second functional ceramic 2, which is Fig. 7 in the upper region of the substrate 1 is designed as a thermistor (NTC thermistor). In particular, the second functional ceramic 2 is an NTC temperature sensor. The substrate 1 has a thermal contact 11. The thermal contact 11 is conductively connected to the second functional ceramic 2. The thermal contact 11 is designed, for example, in the form of a via. The via extends from the top side of the substrate 1 to the second functional ceramic 2.

[0059] By completely embedding the functional ceramics 2 in the inert dielectric ceramic carrier (substrate 1), functional ceramics 2 with completely different properties, such as sintering temperature and expansion coefficient, can be integrated together into the substrate 1. This allows for the realization of extremely adaptive and flexibly usable multilayer components 100.

[0060] In the following, in connection with the Fig. 8a to 8d, a method for producing a multilayer component 100 is described. All features required for the multilayer components 100 in connection with the Fig. 1 to 7 also apply to the procedure and vice versa.

[0061] In a first step, at least one functional ceramic 2 is produced. Preferably, several different functional ceramics 2 are produced, depending on the specific requirements for the multilayer component 100. Depending on the intended use of the respective functional ceramic 2, its production can vary greatly. All functional ceramics 2 have in common that they are sintered before being introduced into the substrate 1.

[0062] For example, to produce functional ceramic 2, ceramic powder is provided and doped with dopants, such as ZnO. The powder is then sintered. This occurs at temperatures greater than or equal to 1000°C and less than or equal to 1300°C, for example, at 1100°C. This process produces functional ceramic 2 in the form of a sintered grain, which is used, for example, as an SMD varistor.

[0063] If a varistor chip is to be formed as functional ceramic 2, a granulate consisting of sintered grains (as described above) is prepared, sieved, and pressed. The pressed granulate is then sintered (1000°C ≥ T ≤ 1300°C) and processed into a disc-shaped varistor chip. The varistor chip is then metallized by sputtering or screen printing.

[0064] In a next step, LTCC green sheets are prepared to form the substrate 1. The green sheets contain, for example, a ceramic powder, a binder, and a glass component. The green sheets 15 are stacked one above the other to form a stack. At least one recess 6 is introduced into the green layers 15 by laser ablation or punching. The recess serves to introduce the functional ceramic 2 into the green stack 16 in a later process step. The number of recesses 6 introduced into the green layers 15 corresponds to the number of functional ceramics 2 in the finished multilayer component 100.

[0065] In a further step, metal structures for forming the internal electrodes 4 are provided, for example, printed, on at least a portion of the green foils 15. The metal structures are preferably applied before the provided green foils 15 are stacked together. The metal structures comprise, for example, Ag, Cu, Pd, or a combination thereof. The metal structures can be specifically shaped, in particular, in a connection region for connecting the functional ceramic 2, as described in connection with the Fig. 4 and Fig. 5 was described.

[0066] Subsequently, at least one functional ceramic 2 is introduced into the recess 6 ( Fig. 8a). The recess 6 is filled with the functional ceramic 2, which is then vibrated into place.

[0067] In a further step, ceramic cover foils 13 are provided in the green state ( Fig. 8a). These are arranged on the top and bottom of the stack of green sheets 15. The cover sheets 13 are free of the recess 6, so that the functional ceramic 2 is now surrounded by ceramic material on all sides. This is followed by lamination and pressing of the green sheets 13, 15 to form a green stack 16 ( Fig. 8b).

[0068] Further recesses are introduced into the green foils 13, 15 by punching or laser processes to create the through-holes 7. These recesses completely penetrate the green stack 16 consisting of the green foils 15 and the cover foils 13. To create the respective through-hole 7, the recess is filled with a bonding material after a sintering step, for example, by depositing a metal from a solution. The recess is preferably completely filled. The metal contains or is, for example, copper, silver, and / or palladium.

[0069] In a further step, the green stack 16 is sintered ( Fig. 8c). The green stack 16 is sintered at a temperature below the sintering temperature of the functional ceramic 2. For example, the sintering temperature of the green stack is 150°C below the sintering temperature for the functional ceramic 2. For example, the sintering temperature is between 750°C and 900°C, including the limits. Sintering of the green stack 16 preferably takes place at 800°C or 850°C. Firing the LTCC ceramic at temperatures significantly below 1000°C no longer affects the grain structure of the functional ceramic 2. The functionality of the functional ceramic 2 can thus be largely retained by appropriately selecting the LTCC ceramic and the sintering process (atmosphere).

[0070] Sintering results in shrinkage of the green sheets 13, 15. The appropriate selection of the LTCC ceramic with defined shrinkage in the z-direction and low shrinkage in the x- and y-direction enables crack-free enclosing of the functional ceramic 2.

[0071] In a final step, the external contacts 5 are provided on the outer surfaces of the sintered green stack 16. For example, a silver paste 14 is arranged on at least a partial area of the outer surfaces ( Fig. 8d) and then fired. List of reference symbols 1 LTTC ceramic / substrate 2 Functional ceramics 3 External contact 4 inner electrode 4a footbridge 4b Constriction 5 Outer electrode 6 recess 7 Via / Through-hole plating 8 Solder connection 9 Contact surface 10 Heat source 11 Thermal contact 13 Cover film 14 Silver paste 15 green foil 16 green stacks 100 multilayer components

Claims

[1] Multilayer component (100) comprising an inert ceramic substrate (1) and at least one functional ceramic (2), wherein the functional ceramic (2) is completely enclosed by the ceramic substrate (1), wherein the functional ceramic (2) comprises a varistor, an NTC ceramic, a PTC ceramic or a ferrite, wherein the multilayer component (100) comprises a plurality of functional ceramics (2), and wherein the functional ceramics (2) have different expansion coefficients and / or different sintering temperatures. [2] Multilayer component (100) according to claim 1, wherein the ceramic substrate (1) comprises an LTCC ceramic. [3] Multilayer component (100) according to one of the preceding claims, wherein the at least one functional ceramic (2) comprises an HTCC ceramic. [4] Multilayer component (100) according to one of the preceding claims, wherein the functional ceramic (2) is designed as an ESD protection element. [5] Method for producing a multilayer component (100) comprising the following steps: - Production of at least one functional ceramic (2), wherein spray granulate, ceramic powder and / or green layers are provided for the production of the functional ceramic (2) and wherein the spray granulate, the ceramic powder and / or the green layers are subsequently sintered; - Providing LTCC green films (15) having at least one recess (6); - providing electrode structures on at least part of the green sheets (15); - introducing the at least one functional ceramic (2) into the recess (6); - Providing cover films (13) in the green state; - laminating and pressing the green films (13, 15) into a green stack (16); - sintering of the green stack (16); - Provision of external contacts (5) on outer surfaces of the sintered green stack (16). [6] Method according to claim 5, wherein the at least one recess (6) is provided by punching or lasering the green films (15). [7] Method according to one of claims 5 or 6, wherein the functional ceramic (2) is sintered at a temperature of greater than or equal to 1000°C. [8] Method according to one of claims 5 to 7, wherein the green stack (16) is sintered at a temperature which is below the sintering temperature of the functional ceramic (2). [9] Method according to one of claims 5 to 8, wherein the green stack (16) is sintered at a temperature of less than or equal to 900°C and greater than or equal to 750°C.

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