Thermistor, electronic component, outer electrode, electronic structure, method for producing an electronic component

Abstract

The application relates to an electronic component having a first outer electrode. Said electronic component has a relief layer which is designed to reduce mechanical or thermomechanical loads on a functional body located below the outer electrode. Furthermore, the outer electrode has a terminating outer layer which is thinner than the relief layer.

Description

[0001] P2024, 1165 WO N 3 December 2025

[0002] 1

[0003] Description

[0004] Thermistor, electronic component, external electrode, electronic structure, method for manufacturing an electronic component

[0005] The present application relates to a thermistor, an electronic component, an external electrode, an electronic assembly and a method for manufacturing an electronic component.

[0006] In the field of temperature measurement in electronic applications or in electronic setups, such as on printed circuit boards or similar systems, NTC temperature sensors can be used, for example. For this purpose, NTC temperature sensors, as well as other electronic components, are arranged and mounted on printed circuit boards or, more generally, on substrates.

[0007] Factors such as long-term stability or suitability for higher operating temperatures, such as up to 200 °C or even above, play a role here.

[0008] Existing temperature sensors are described, for example, in WO 2016 / 012311 Al or WO 2016 / 012310 Al. However, the inventors of the present invention have recognized disadvantages of the designs shown therein. Disadvantages of previous designs include, for example, the fact that contacting still has to be done by soldering, which can entail cleaning steps, thus complicating the contacting process. Furthermore, encapsulation with glass is often required, e.g., to protect electrical contacts. P2024, 1165 WO N 3 December 2025

[0009] 2

[0010] When contacting such arrangements, especially in the case of solderless contacting methods, stresses can occur that can, for example, impair temperature stability or long-term stability.

[0011] In view of the problems mentioned above, it is an object of the present invention to provide at least an alternative or improved electronic component, an alternative or improved external electrode, an alternative or improved electronic assembly, or an alternative or improved method for manufacturing an electronic component.

[0012] This problem is solved at least partially by the subject matter of claim 1 or by subject matter of dependent claims. Dependent claims describe embodiments that may have other advantages or alternative designs.

[0013] According to a first embodiment, an electronic component is described. This electronic component has a first outer electrode. The first outer electrode has a thick film. Such a thick film can contain silver or gold, with silver being clearly preferred for cost reasons. According to a particularly preferred embodiment of the present design, the outer electrode further has a final, purely metallic outer layer. This outer layer is thinner than the thick film.

[0014] The term "electronic component" can be understood here and in the following as anything that is considered in the field to be P2024, 1165 WO N 3 December 2025

[0015] 3. Such is understood. In particular, it can be an active or passive electronic component. The observations and developments described below were made by the inventors specifically with NTC temperature sensors (negative temperature coefficient temperature sensors). However, these observations are transferable to a large number of other components and are not limited to NTC temperature sensors. Nevertheless, a temperature sensor, and in particular an NTC temperature sensor, is a preferred embodiment of an electronic component. Other preferred embodiments may be other ceramic-based electronic components. For example, they may be PTC thermistors or varistors, or similar.

[0016] According to one embodiment, the external electrode can be arranged on a functional body that gives the electronic component its functionality. In particular, the external electrode can be arranged on a side surface of the functional body. In the case of a ceramic-based electronic component, the functional body can be a ceramic or at least ceramic-containing functional body. In the case of a thermistor (e.g., NTC or PTC), it can be a ceramic thermistor functional body (e.g., NTC or PTC).

[0017] According to a preferred embodiment, two electrodes are arranged on the functional body. For example, a second electrode is arranged on another, in particular on an opposite, side face of the base body. The electronic component is, for example, cuboid in shape. The electrodes are arranged, for example, on a top and bottom surface of the functional body. P2024, 1165 WO N 3 December 2025

[0018] 4

[0019] However, the electronic component is not limited to this form.

[0020] In the specific embodiment of an NTC thermistor, the inventors of the present invention recognized that contacting a component can place a high stress on the functional body. Examples of such contacting methods are pressure silver sintering or thick-wire bonding. Existing designs, including those shown in WO 2016 / 012311 Al or WO 2016 / 012310 Al, may be poorly suited or unsuitable for such contacting methods.

[0021] The above-mentioned construction allows the thick film to at least partially compensate for stresses, particularly mechanical or thermomechanical stresses. This reduces the stress on the functional body. With previous designs, especially those with electrodes comprising only thin films, as shown, for example, in WO 2016 / 012311 Al or WO 2016 / 012310 Al, the stress on the functional body can be increased compared to a design according to the invention.

[0022] At the same time, the purely metallic outer layer can provide a good contact surface for contacting. For example, a more stable contact can be achieved through pressure silver sintering or thick wire bonding.

[0023] During silver printing, especially double-sided silver printing, high mechanical or thermomechanical stresses are placed on the electronic components. P2024, 1165 WO N 3. December 2025

[0024] 5

[0025] The component is subjected to pressures of several tens of MPa, such as 10 MPa to 30 MPa, while simultaneously heating. Thin-film electrodes, in particular, can transmit the stress to the functional body, thereby damaging it or compromising the electrode connection and causing it to detach.

[0026] During pressure silver sintering, and especially during double-sided pressure silver sintering, the different coefficients of thermal expansion of the materials and the rigid clamping of the components can lead to tensile stresses on the electronic component, or particularly on a functional body such as an NTC ceramic body. This can, for example, lead to cracks in a ceramic structure. Consequently, it can result in increased resistance, impaired function, or complete detachment of an outer electrode.

[0027] To reduce the stresses imposed on a functional body, the inventors have found that it is advantageous to have a thick layer according to the invention that is suitable for absorbing stresses in the metallization and thus reducing the load on the ceramic. With metallization layers that are too thin, tensile stresses are transferred into the ceramic and can thus lead to the formation of the defects mentioned above.

[0028] Furthermore, the inventors recognized that it can be advantageous to have a purely metallic outer layer, as in a thin-film electrode. Pure thick-film electrodes, which are formed, for example, as baked-on layers, are often not purely metallic on their surface. For instance, glass islands made of P2024, 1165 WO N 3. December 2025

[0029] 6. Glass frit may have formed in the paste to be fired, or may be present, or may be formed during pressure silver sintering. In particular, the conditions during pressure silver sintering can lead to an accumulation of glass islands on the surface or at the resulting interface. This can weaken the contact. The outer layer can provide a more stable bond in this case.

[0030] Thick-wire bonding with bond wire thicknesses of 200 g / m or more, such as 200 to 500 g / m, can be advantageous for a wide variety of applications, particularly in power modules or high-current applications. The inventors recognized that thick-wire bonding also places high stresses on the electronic component. Existing thin-film electrodes are sometimes unable to withstand these stresses adequately, which is why they are unsuitable or only partially suitable for corresponding bond wire thicknesses. For example, the inventors observed with NTC thermistors that the ceramic body of conventional thin-film electrodes was damaged when contacted via thick-wire bonding with corresponding bond thicknesses. In a structure according to the invention, the thick-film can absorb the stresses of the clamping force and the ultrasound during bonding. The outer layer can be made of a material suitable for the thick-wire bond contact or the thick wire itself.

[0031] According to one embodiment, which may be particularly preferred in the case of pressure silver sintering, the outer layer contains or consists of silver. A thin outer layer containing or consisting of silver is well suited for application by pressure silver sintering. P2024, 1165 WO N 3 December 2025

[0032] 7

[0033] According to another preferred embodiment, the outer layer comprises a material or metal particularly suitable for thick wire bonding. In particular, the thick wire preferably contains aluminum or copper. The cover layer may comprise a suitable material.

[0034] The inventive structure can combine several advantages of thick-film electrodes and thin-film electrodes. The thick film can offer the advantages mentioned above.

[0035] If only a thick film were used, direct contact of an aluminum bonding wire on silver (thick film) could easily lead to corrosion or other chemical degradation under the influence of moisture or in sulfur-containing environments. In the case of a gold thick film, the application of an aluminum wire can result in Kirkendall voiding. This involves the formation of intermetallic phases and a resulting volume decrease, which can lead to the formation of voids and ultimately to the dissolution of the bond. The outer layer allows for the selection of a suitable material to mitigate these risks.

[0036] According to a particularly preferred embodiment in connection with the points mentioned above, the outer layer contains gold or platinum. These materials are especially suitable for the application of thick-wire bonds, particularly aluminum-based thick-wire bonds. According to one embodiment, the bond wire can have a thickness exceeding 200 pm, e.g., 200 to 500 pm. Contacting via thick-wire bonding in general, and particularly with the aforementioned bond wire thicknesses, can be advantageous for high currents or power levels. P2024, 1165 WO N 3 December 2025

[0037] 8

[0038] According to another implementation, the thick film is produced by a different process than the outer layer. This has the advantage that different production methods can be selected to complement each other for the different functions and resulting different properties of the layers in the outer electrode.

[0039] According to one embodiment, the thick film is a baked-on electrode layer. Baked-on electrode layers are easy to produce, and layers of a thickness advantageous for compensating the aforementioned stresses can be readily provided. Preferably, baked-on electrode layers contain, in addition to the metal material, such as silver, a glass frit. For example, the mass fraction of silver can be between 70 and 90 percent by mass. Alternatively or additionally, a volume fraction of the metal can be, for example, 30 to 70 percent. The aforementioned construction with the purely metallic outer layer, as already explained above, is particularly advantageous for such an embodiment.

[0040] According to another embodiment, the outer layer can be applied or produced by a thin-film process. A preferred example of such a thin-film process is sputtering, such as magnetron sputtering. Alternatively, other processes such as physical vapor deposition, atomic layer deposition, or pulsed laser deposition can also be used. Such thin-film processes have the advantage of being able to form continuous metallic layers with a small thickness. They can provide a good direct bonding surface for the contacting methods mentioned above. The property that such P2024, 1165 WO N 3 December 2025

[0041] 9

[0042] Layers, when applied directly to a ceramic body or other functional body, are less able to withstand mechanical stresses; this is counteracted, as explained above, by the thick silver-containing layer.

[0043] According to a further and preferred embodiment, the outer layer is formed as a continuous cover layer. This can mean that the outer layer has no gaps, at least in the area intended for contacting. Preferably, the outer layer can be formed over the entire surface of an outer electrode.

[0044] According to another preferred embodiment, the thick silver-containing layer can have a minimum thickness of over 10 pm. The inventors of the present invention have recognized that a minimum thickness of over 10 pm can be sufficient to effectively reduce stresses, for example, when using the aforementioned processes. In pressure silver sintering, but especially in thick-wire bonding, a thickness of over 10 pm has proven advantageous. According to embodiments, a minimum thickness of 12 pm or more, 15 pm or more, or 17 pm or more is possible, as the effects can be more pronounced at these thicknesses. A minimum thickness of 20 pm or greater is particularly preferred. The inventors have found that at a corresponding thickness, electrode detachment can be prevented even more effectively, or the stresses on a functional body can be avoided even more effectively.For example, in the case of a baked-on layer, a thick layer of 20 pm or more can be produced by applying two layers of a paste for a baked-on layer P2024 , 1165 WO N 3 . December 2025.

[0045] 10

[0046] A layer is applied and then fired. A thickness of at least 20 g / m has proven particularly advantageous for printing silver sintering. According to one embodiment, a thickness of 10 g / m or more may be sufficient, for example, for thick wire bonding.

[0047] According to another embodiment, which may be preferred, the thickness of the thick silver-containing layer is less than 100 g / m. Preferably, the layer is less than 30 g / m. The inventors of the present invention have recognized that at a thickness of 20 g / m, the aforementioned advantages are even more fully realized. Regarding the upper limits mentioned here, the inventors have recognized that for such maximum thicknesses, manufacturing process tolerances can be higher, yet a targeted minimum thickness can still be easily achieved without excessive material consumption.

[0048] According to a further and preferred embodiment, the outer layer can have a thickness of 1 g / m or less. The inventors of the present invention have recognized that corresponding layer thicknesses are easily achievable by the above-mentioned methods. Layer thicknesses of less than 1 g / m help to avoid unnecessary material or time expenditure in the application using the above-mentioned method.

[0049] According to one exemplary embodiment, a minimum thickness of the outer layer can be 100 nm. A minimum thickness of 100 nm can help ensure that deformations or material movements do not lead to a breach of the outer layer, even in the case of temperature exposure. For example, a minimum thickness can also be greater than 100 nm (P2024, 1165 WO N 3 December 2025).

[0050] 11 and, for example, 200 nm or greater, 300 nm or greater, or 450 nm or greater. For example, a thickness may be 100 nm or greater and 1.4 pm or less. The other examples of minimum thicknesses may, according to embodiments, replace the lower limit mentioned here. According to another preferred embodiment, a thickness of the outer layer may be 500 nm or less, or more preferably 450 nm or less, to reduce material or application time. In some cases, such as a gold-containing outer layer intended for aluminum bonding, a layer thickness may preferably be less than 300 nm. In such a case, a layer thickness may be between 100 nm and 300 nm. For example, a thickness of about 200 nm, such as 200 ± 50 nm or 200 ± 25 nm .

[0051] In another embodiment, a separating layer can be arranged between the thick layer and the outer layer. In some cases, a separating layer can improve the bond between the outer layer and the thick layer. The separating layer can rest directly on the thick layer. Additionally or alternatively, the outer layer can be arranged directly on the separating layer.

[0052] Furthermore, according to one implementation, the interface layer can have a different material than that of the outer layer or the thick film. This can have the advantage that, for example, in the case of the aforementioned formation of intermetallic phases, these are stopped at the interface layer. Thus, for example, a gold-containing outer layer can also be used for aluminum thick wire bonding. The small amount of gold material available in the final layer, which is available up to the interface layer, is P2024, 1165 WO N 3. December 2025

[0053] 12 is hardly suitable here to weaken the contact via Kirkendall voiding.

[0054] According to one embodiment, the separating layer can, for example, comprise materials such as copper, titanium, chromium, nickel, palladium, or platinum. These materials have proven particularly suitable for achieving the aforementioned properties. Nickel is especially preferred in this regard.

[0055] According to another embodiment, the separating layer can have a single-layer structure. For example, the single-layer separating layer can contain or consist of the materials mentioned above.

[0056] According to one embodiment, the separating layer can also be a layer in a multilayer structure. For example, a first separating layer made of a first material and a second separating layer made of a second material can be arranged one above the other. The second separating layer can be arranged on top of or above the first separating layer. The first separating layer can be arranged above, or preferably on top of, the thick layer. The outer layer can be arranged above, or preferably on top of, the second separating layer. The materials of the separating layers can each be selected from those mentioned above for the separating layer. Preferably, the material of the first separating layer differs from the material of the second separating layer. The first separating layer can, for example, contain or consist of nickel or titanium.The second separating layer can, for example, contain or consist of chromium, palladium, platinum, or copper. For example, a separating layer can contain P2024, 1165 WO N 3. December 2025.

[0057] 13

[0058] Separation layers have the following layering: nickel-chromium, titanium-palladium, titanium-platinum or nickel-copper.

[0059] As the term multilayer structure indicates, such a structure can contain two or even more than two sublayers. These can, for example, consist of the materials mentioned above.

[0060] According to another embodiment, which may be preferred, the separating layer or a separating sublayer of the separating layer can be produced by or using a thin-film process. This could, for example, be one of the processes mentioned above. It may be particularly preferred that the same process used for the outer layer is employed.

[0061] According to another embodiment, the separating layer can have a thickness of 1.2 pm or less. Such thicknesses are easily achievable using a thin-film process. In this thickness range, the aforementioned advantages can be achieved without making the layer unnecessarily thick. It may be preferred that the minimum thickness be 200 nm. A maximum thickness can be 1.2 pm. In the resulting range from 200 nm to 1.2 pm, the aforementioned advantages can be particularly pronounced.

[0062] As explained above, according to one embodiment it may be preferred that the electronic component has a second electrode.

[0063] According to one embodiment, the first electrode can have the above-mentioned structure and the second electrode a P2024 , 1165 WO N 3 December 2025

[0064] exhibit 14 thick silver- or gold-containing layers.

[0065] In the simplest version of this design, the second outer electrode can consist of such a thick film. Such a pure thick-film electrode is easy to produce. For example, although some disadvantages may be incurred, the second electrode can be used for contacting via pressure silver sintering, and a bond connection can be established via the first electrode. In particular, it may be preferable for the outer layer of the first outer electrode not to contain silver. For example, it could contain gold or platinum. In this case, the same process can be used for producing the outer layers of the first and second electrodes. Only one electrode then needs to be provided with additional layers. This can be preferable compared to the examples explained below, since these require different materials to be provided and applied for different outer layers.

[0066] According to one embodiment, it may be preferred that the thick film of the second electrode has a metal content of at least 75 wt.%, or preferably at least 80 wt.%, or even at least 85 wt.%. Such a content can enable fewer glass frit islands to form on the surface or at the interface.

[0067] According to one embodiment, an electronic component can also be configured such that the first outer electrode has any of the above-mentioned structures and the second outer electrode has the same structure. Alternatively, the second outer electrode can have any other structure described above in relation to the first outer electrode. P2024, 1165 WO N 3 December 2025

[0068] 15

[0069] According to a preferred embodiment, both the first outer electrode and the second outer electrode have a silver-containing outer layer or an outer layer made of silver. Such a structure can be particularly suitable for double-sided contacting by means of pressure silver sintering.

[0070] According to another preferred embodiment, an electronic component can also be configured such that the first outer electrode has the structure described above, and the second outer electrode has a silver-containing thick film and a final outer layer, wherein the outer layer comprises platinum or gold. Alternatively, for variants of this embodiment, the properties or advantages mentioned above for the first outer electrode can also apply to the second outer electrode. According to a preferred embodiment, the first outer electrode can have a silver-containing outer layer. In this case, contact can preferably be established via the first outer electrode by pressure silver sintering, and contact can be established via the second outer electrode by thick-wire bonding.

[0071] According to one embodiment, which applies in particular to an NTC thermistor, the volume of the electronic component can be between 0.0001 mm²3 and 9 mm 3 It should preferably be between 0.008 mm. 3 and 3 mm 3 Even more preferred is a volume between 0.01 mm 3 and 2 mm 3 Alternatively, a volume between 0.004 mm³ is possible. 3 and 2.4 mm 3 Dimensions can be, for example, between 0.2 x 0.2 x 0.1 mm. 3 and 2 x 2 x 0.6 mm 3 The size of electronic components is not generally limited; the sizes specified here, in particular the preferred ranges P2024, 1165 WO N 3, December 2025, are not applicable.

[0072] However, 16 are suitable for a large number of relevant applications.

[0073] Furthermore, the present invention is not limited to the aforementioned layer systems, materials, or manufacturing methods. In particular, the inventors have identified a generalized electronic component with a first outer electrode comprising a stress-relieving layer and an outer layer. The stress-relieving layer is designed to reduce mechanical or thermomechanical stresses on a functional body located beneath the outer electrode. The outer layer is thinner than the stress-relieving layer. The thick layer represents one form of the stress-relieving layer. All the above statements can also apply to the generalized stress-relieving layer as independent embodiments.

[0074] Similarly, an external electrode is described independently of a functional body or other features of an electronic component. This electrode can possess the properties mentioned above or below. The use of such an electrode is also described in this context, in particular its use as an electrode of an electronic component.

[0075] Furthermore, an electronic setup with one of the aforementioned electronic components is described. In such a setup, one or more external electrodes can be connected via pressure silver sintering. Alternatively, one or more external electrodes can be connected via thick-wire bonding. It is also possible for a first external electrode to be contacted via pressure silver sintering and a second external electrode via thick-wire bonding. P2024, 1165 WO N 3 December 2025

[0076] 17

[0077] Depending on the implementation of an electronic assembly, the electronic component can be arranged on or above a substrate. For example, it can be connected to one or more corresponding terminals via one or more of the contacting methods mentioned above.

[0078] Furthermore, a method for manufacturing an electronic component is provided. The aforementioned properties can apply to this component according to its various implementations. Furthermore, features found in the method can also apply to the electronic component.

[0079] According to one embodiment of the process for manufacturing an electronic component, a baked-on thick film is first produced. For this purpose, a metal-containing paste is applied to or over a functional body. This paste is then baked on. The metal can be present in the paste as metal powder together with other additives and / or a glass frit. The baking temperature can be, for example, between 600 °C and 1000 °C, or between 700 °C and 900 °C. Preferably, the thick film is silver-containing and is produced by baking on a silver-containing paste.

[0080] According to one embodiment, a purely metallic outer layer is further formed by a thin-film process. The above-mentioned processes are preferably used, in particular a sputtering process. According to one embodiment, any separating layer can be produced by a thin-film process. The above-mentioned P2024, 1165 WO N 3 December 2025

[0081] 18

[0082] Methods are preferably used, in particular a sputtering method.

[0083] Furthermore, methods for contacting an electronic component are described which may exhibit the aforementioned features.

[0084] Further embodiments may arise from the explanations of the exemplary embodiments described below. The invention is not limited to the exemplary embodiments shown below. In particular, exemplary embodiments are explained with reference to figures. In the figures, both absolute dimensions and ratios may be distorted. The invention is not limited to the dimensions or ratios shown. Unless otherwise stated, no dimensions or ratios can generally be derived from the figures.

[0085] Figure 1 shows a first embodiment of an electronic component.

[0086] Figure 2 shows a second embodiment of an electronic component.

[0087] Figure 3 shows a third embodiment of an electronic component.

[0088] Figure 4 shows a fourth embodiment of an electronic component.

[0089] Figure 5 shows a first embodiment of an electronic setup. P2024, 1165 WO N 3 December 2025

[0090] - 19 -

[0091] Figure 6 shows a second embodiment of an electronic setup.

[0092] Figure 1 shows a first embodiment of an electronic component 1. The electronic component 1 is an NTC thermistor with a functional body 2, which is an NTC functional body. The NTC functional body can comprise a common NTC ceramic, such as a ceramic with a spinel or perovskite structure. The electronic component has a width and depth of 1.6 ± 0.15 mm and a height of 0.5 ± 0.1 mm.

[0093] A first outer electrode 3 and a second outer electrode 4 are arranged on the functional body 2. Both have the same basic layer structure. Both have a thick layer 3DS or 4DS, respectively, which is arranged directly on the functional body 2. A separating layer 3T or 4T is arranged on the thick layer 3DS or 4DS, respectively. Both outer electrodes 3 and 4 are sealed by a final outer layer 3AS or 4AS, respectively.

[0094] The thick films 3DS and 4DS are baked-on layers containing silver with a silver content of 70 wt.% to 90 wt.%. They have a thickness of at least 20 pm. This allows them to compensate for mechanical or thermomechanical stresses, such as those that can occur during contacting by pressure silver sintering or thick-wire bonding. The inventors have found that a thickness of over 10 pm already provides significant improvements compared to previously known external electrodes. P2024, 1165 WO N 3 December 2025

[0095] 20 is possible. Alternatively, the thick layers 3DS and 4DS can also be gold-based.

[0096] To produce the 3D and 4D thick layers, a silver-containing paste is applied to the functional body 2. In addition to the metal, the paste contains other additives such as binders or solvents, as well as a glass frit. The paste can be applied using screen printing. To achieve a thickness of 20 µm, two layers of the paste can be applied before a firing step is performed. After printing the first layer, a drying step is carried out before the second layer can be printed. The two superimposed layers are dried again before firing. The firing temperature is between 700 °C and 900 °C.

[0097] The 3T and 4T separating layers are sputtered nickel-based layers. Preferably, these consist entirely of nickel, but can also contain additives, such as sputtering aids. Examples include a vanadium content, which can be between 5 wt% and 10 wt%, or 7 wt%. Alternatively, the 3T and 4T separating layers can consist of the materials mentioned above. The thickness of the 3T and 4T separating layers is between 200 nm and 1.2 pm. The separating layers can improve adhesion between adjacent layers and can also act as a material barrier.

[0098] The outer layers 3AS and 4AS are sputtered silver-containing layers. Preferably, these consist of silver. The thickness of the outer layers 3AS and 4AS is between 100 nm and 600 nm. The outer layers 3AS and 4AS are continuous over the entire outer surface of the respective outer electrodes 3 and 4. P2024, 1165 WO N 3. December 2025

[0099] 21 trained. The outer layers 3AS and 4AS enable stable contact via double-sided printing! Ibers internal.

[0100] Figure 2 shows a second embodiment of an electronic component 1. The structure of this electronic component 1 corresponds to that of the first embodiment, except for the separating layers. Instead of separating layers 3T and 4T in the first embodiment, separating layers in a multilayer structure with two separating sublayers each are formed.

[0101] The first separating layers 3T1 and 4T1 contain nickel and are each arranged on the thick layer 3DS and 4DS, respectively. The first separating layers preferably consist of nickel, whereby the considerations mentioned above regarding a nickel layer from the first embodiment can apply accordingly. The second separating layers 3T2 and 4T2 are arranged on the respective underlying first separating layer 3T1 and 4T1 and contain or consist of chromium. Both separating layers are sputtered layers. The total thickness of the separating layer consisting of both separating layers in the multilayer structure is between 200 nm and 1.5 pm.

[0102] Figure 3 shows a third embodiment of an electronic component 1. The structure of the electronic component 1 corresponds to that of the first embodiment, except for the structure of the second external electrode 4. P2024, 1165 WO N 3 December 2025

[0103] 22

[0104] The first outer electrode is specifically finished with a silver-containing outer layer 3AS and is therefore particularly suitable for pressure silver sintering.

[0105] The second outer electrode 4 also has a layered structure similar to that of the first embodiment, except that the outer layer 4AS is a gold-containing sputtered layer. Preferably, the outer layer 4AS consists of gold. The gold-containing outer layer 4AS is particularly suitable for contacting via thick-wire bonding, since the thin gold layer is largely chemically inert and therefore not prone to corrosion. Alternatively, the outer layer 4AS can contain or consist of platinum.

[0106] Furthermore, the thickness of the outer layer 4AS, ranging from 100 nm to 300 nm, allows for reliable contact with aluminum wires without the risk of Kirkendall voiding compromising the contact. This thickness is insufficient to form significant voids. Additionally, the separating layer 4T, which contains nickel, acts as a material barrier. The aforementioned thickness is preferred for the outer layer intended for aluminum wire bonding. It can also be approximately 200 nm, for example, 200 ± 50 nm or 200 ± 25 nm. If the layer is thicker than 300 nm, the risk of Kirkendall voiding at elevated temperatures increases. If the layer is much thinner than 200 nm, e.g., thinner than 100 nm, prior processing, such as soldering or silver sintering, can lead to nickel enrichment on the gold surface due to nickel diffusion occurring at temperatures above 200°C. P2024, 1165 WO N 3 December 2025

[0107] 23

[0108] Figure 4 shows a fourth embodiment of an electronic component 1. The structure of this electronic component 1 corresponds, except for the structure of the first outer electrode 3, to that described in the third embodiment. In particular, the second outer electrode 4 is especially suitable for contact via thick-wire bonding, as explained above in the third embodiment.

[0109] The first outer electrode 3 consists exclusively of a silver-containing thick film, which was produced as described in the first embodiment. It has a metal content of 80 wt.% or more. This has the advantage that fewer glass islands, which are attributable to the glass frit, are present at the contact point of a pressure-silver sintered connection than with lower metal content. This design can be particularly cost-effective, since, unlike in the third embodiment, no different outer layers need to be applied. The process can therefore be simplified, although there may be disadvantages in the quality of the pressure-silver sintered connection via the first electrode.

[0110] Figure 5 shows a first embodiment of an electronic assembly. For example, the electronic assembly consists of an arrangement of an electronic component 1 on a printed circuit board (PCB) as a substrate. Conductive traces 6 and 11, which can be arranged on a PCB, are shown. The conductive traces 6 and 11 are each connected to contact pads 5 and 10. The conductive traces 6 and 11 and the contact pads 5 and 10 contain copper or consist of copper. P2024, 1165 WO N 3. December 2025

[0111] 24

[0112] On contact surface 5, the electronic component 1, as described for the third embodiment, is arranged with the first outer electrode 3 on the contact piece by means of pressure silver sintering. The layer structure of the outer electrodes 3 and 4 is indicated here in Figure 5, but not shown in detail for the sake of simplicity. For pressure silver sintering, a silver powder or a silver powder-containing paste is applied to the contact surface 5 or the silver-containing outer layer 3AS and sintered by heating and pressure of 10 to 30 mPa. The silver-containing thick film 3DS can compensate for stresses arising in this process, such as thermomechanical stresses caused by the different coefficients of expansion of the conductor track and the outer electrode 3, and detachment of the outer electrode 3 or cracks in the ceramic can be better prevented.

[0113] The second outer electrode 4, with its gold-containing outer layer 4AS, is contacted by means of thick-wire bonding. The thick wire 8 used here has a thickness of 300 pm and is made of aluminum. It was bonded by ultrasonic bonding under high pressure, creating the pressed contact area 8. The thick layer 4DS can withstand the stress occurring in this process, so that the ceramic is not damaged. Similarly, the other end of the thick wire is bonded to the contact surface 10, creating the contact area 9.

[0114] Alternatively, for example, the fourth embodiment of an electronic component can also be connected here. P2024, 1165 WO N 3 December 2025

[0115] 25

[0116] Figure 6 shows a schematic cross-section of a second embodiment of an electronic structure. Here, an electronic component 1 according to the first or second embodiment is connected to two contacts 12 and 12' respectively by means of double-sided pressure silver sintering.

[0117] The layer structure of the outer electrodes 3 and 4 is not shown, but corresponds to that which was explained in the aforementioned exemplary embodiments. The contacts 12 and 12' bond to the outer layers 3AS and 4AS of the outer electrodes 3 and 4. The conditions for pressure silver sintering can be those described above for the first exemplary embodiment of an electronic structure.

[0118] P2024, 1165 WO N 3 December 2025

[0119] 26

[0120] Reference character list

[0121] 1 electronic component

[0122] 2 functional bodies

[0123] 3 first external electrode

[0124] 3AS outer layer

[0125] 3DS thick film

[0126] 3T separating layer

[0127] 3T1 first separation layer

[0128] 3T2 second separation layer

[0129] 4 second external electrode

[0130] 4AS outer layer

[0131] 4DS Thick Film

[0132] 4T separating layer

[0133] 4T1 first separation layer

[0134] 4T2 second separation layer

[0135] 5 contact area

[0136] 6 conductor track

[0137] 7 Thick wire

[0138] 8 Contact area

[0139] 9 Contact area

[0140] 10 contact area

[0141] 11 conductor track

[0142] 12 Contact

[0143] 12 ' Contact

Claims

P2024, 1165 WO N 3 December 2025 27 Patent claims 1. Thermistor comprising a ceramic thermistor functional body and two external electrodes thereon, each having a baked-on silver-containing thick film of over 10 pm thickness, arranged on or above the thermistor functional body and designed to at least partially compensate for mechanical or thermomechanical stresses that may occur as a result of pressure silver sintering of the thermistor, comprising a final all-metallic silver-containing outer layer produced by a thin-film process and having a thickness of less than 1 pm, and comprising a single-layer or multi-layer separating layer arranged between the thick film and the outer layer and comprising a material other than silver.

2. Thermistor comprising a ceramic thermistor functional body and a first outer electrode and a second outer electrode thereon, wherein the first outer electrode has a baked-on silver-containing thick film of over 10 pm thickness, arranged on or above the thermistor functional body and designed to at least partially compensate for mechanical or thermomechanical stresses that may occur as a result of pressure silver sintering of the first electrode, the second outer electrode having a baked-on silver-containing thick film of at least 10 pm thickness, arranged on or above the thermistor functional body and designed to compensate for mechanical or thermomechanical stresses that may occur as a result of pressure silver sintering of the first electrode P2024, 1165 WO N 3 December 2025 28 To at least partially compensate for stresses occurring during thick-wire bonding to the second electrode, the second electrode continues to have a final all-metallic outer layer containing gold or platinum, produced using a thin-film process and having a thickness of less than 300 nm, and the second outer electrode has a single-layer or multi-layer separating layer arranged between the thick film and the outer layer.

3. Electronic component comprising a first outer electrode having a thick silver-containing or gold-containing thick film and a final all-metallic outer layer, wherein the outer layer is thinner than the thick film.

4. Electronic component according to claim 3, wherein the outer layer contains silver.

5. Electronic component according to claim 3, wherein the outer layer contains gold or platinum.

6. Electronic component according to one of claims 3 to 5 , wherein the thick layer was produced by a different process than the outer layer .

7. Electronic component according to one of claims 3 to 6 , where the thick film is a baked-on electrode layer .

8. Electronic component according to one of claims 3 to 7 , wherein the outer layer is an electrode layer applied using a thin-film process such as sputtering . P2024, 1165 WO N 3 December 2025 29 9. Electronic component according to one of claims 3 to 8 , wherein the outer layer is a continuous covering layer of the electrode .

10. Electronic component according to one of claims 3 to 9 , wherein the thick layer has a minimum thickness of over 10 pm or preferably of at least 20 pm .

11. Electronic component according to one of claims 3 to 10 , wherein the outer layer has a thickness of at most 1 pm or preferably of 100 nm to 600 nm .

12. Electronic component according to one of claims 3 to 11 , wherein the thick film is designed to at least partially compensate for mechanical or thermomechanical stresses on a functional body located under the outer electrode that may occur during or as a result of contacting the electrode.

13. Electronic component according to one of claims 3 to 12 , wherein a separating layer is arranged between the thick layer and the outer layer .

14. Electronic component according to claim 13, wherein the separating layer has a single-layer structure or a multi-layer structure, wherein one or more layers of such structures comprise copper, titanium, chromium, nickel, palladium or platinum.

15. Electronic component according to claim 12 or claim 13 , wherein the separating layer has a thickness of 2 pm or less P2024, 1165 WO N 3 December 2025 30 and / or can be produced using a thin-film process step.

16. Electronic component according to one of claims 3 to 15 comprising a second outer electrode, comprising a thick silver-containing or gold-containing thick layer.

17. Electronic component comprising a first outer electrode and a second outer electrode, wherein the first outer electrode has the properties described in at least one of claims 3 to 15 and the second outer electrode independently has the properties described in at least one of claims 3 to 15 therein with respect to the first electrode.

18. Electronic component according to any one of claims 3 to 15 comprising a second outer electrode comprising a silver-containing thick layer and a final outer layer, wherein the outer layer comprises gold or platinum.

19. Electronic component comprising a first outer electrode which has a relief layer designed to reduce mechanical or thermomechanical stresses on a functional body located below the outer electrode and a final outer layer which is thinner than the relief layer.

20. Electronic component according to one of claims 3 to 19, which is a thermistor or preferably an NTC thermistor. P2024, 1165 WO N 3 December 2025 31 21. Outer electrode for an electronic component comprising a thick layer of silver or gold and a final all-metallic outer layer, wherein the outer layer is thinner than the thick layer.

22. Electronic structure comprising a carrier with a connection point and an electronic component according to claim one of claims 3 to 20, wherein the first outer electrode is arranged at the connection point via pressure silver sintering.

23. Electronic structure comprising a carrier and an electronic component according to claim one of the claims 3 to 16 , wherein the first outer electrode is electrically contacted via thick wire bonding .

24. Electronic structure comprising a carrier with a connection point and an electronic component according to claim 19, the first outer electrode being arranged at the connection point via pressure silver sintering and wherein the second outer electrode being electrically contacted via thick wire bonding.

25. Method for manufacturing an electronic component, comprising the steps Forming a baked-on silver-containing thick film by applying a silver-containing paste to or over a functional body of the electronic component and baking the silver-containing paste, and forming a purely metallic outer layer by a thin-film process, wherein the outer layer is thinner than the thick film.

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