DE102020107311B4 - Process for the fine structuring of metal-containing layers and ceramic multi-layer component - Google Patents

Abstract

Method for the fine structuring of coarsely structured, pasty, metal-containing layers (3), comprising the following steps: - applying a metal-containing layer (3) which has a coarse structure and comprises a pasty material whose main components are one or more metals and an organic solvent, onto a surface of a ceramic layer (2), which comprises a green film, - scanning the position and area of the metal-containing layer (3) and generating a data set from the recorded data, - evaluating the data set by comparing it with specified values, - determining critical sections of the metal-containing layer (3) that deviate from the specified values, - decomposition of the critical sections by laser irradiation into a metal-containing powder, the coarsely structured metal-containing layer (3) being converted into a desired finely structured layer (3), - sintering of the ceramic layer (2 ) and the metal-containing layer (3) applied thereto according to it subsequent fine structuring.

Description

The present invention relates to a method for the fine structuring of coarsely structured, pasty metal-containing layers. The invention further relates to a ceramic multilayer component which comprises finely structured metal-containing layers.

A large number of electronic components include ceramic layers with metal-containing layers applied and structured thereon. The metal-containing layers are structured in such a way that sections of integrated electronic elements result. The ceramic and metal-containing layers can be stacked to form multi-layer components. Care must be taken to ensure that the stacking is accurate, so that sections of integrated electronic elements that belong together lie on top of one another. These can then be connected by vias in the ceramic layers.

In addition, the electronic components can include other technical arrangements such as antennas, for example, which are insulated from the metal-containing layers. In order to avoid capacitive and/or inductive interactions between current-carrying layers containing metal and other technical arrangements, the distance between them must not fall below a required minimum distance.

Furthermore, for example, the distance between an antenna and the structured metal-containing layer should not vary in order to avoid interference signals and an influence on the impedance in the antenna. This applies within a metal-containing layer, but also in particular if the antenna extends over several metal-containing layers.

In order to maintain the required accuracy in the structuring of the metal-containing layers applied, the dimensions of such layers and the stack height of an electronic component and the size of the integrated electronic elements are limited in the case of manufacturing processes that have been customary up to now.

An industrial process for applying a metal-containing layer to a ceramic layer is the screen printing process.

With such a method, sections of integrated electronic elements with a width of less than 50 μm cannot be mass-produced. The number of possible electronic elements on a ceramic layer of a certain size is therefore limited.

On the other hand, the sections of the integrated electronic elements can only be applied to a ceramic layer with a limited accuracy. Position inaccuracies of up to +/-30 µm cannot be avoided in serial production up to now. On the one hand, this can lead to layer misalignment within such integrated electronic elements that extend over several stacked metal-containing and ceramic layers. This can result in unwanted electrical losses. On the other hand, this can lead to different distances between the integrated electronic elements and other technical arrangements such as antennas, which results in unwanted electrical losses and interference signals.

Due to this limited accuracy, metal-containing layers can only be produced up to a certain maximum dimension with the usual methods. If this maximum dimension is exceeded, the influence of positional inaccuracies of the integrated electrical elements becomes too great.

An exemplary manufacturing process is described in the publication DE 690 08 459 T2 described. Furthermore, the document JP H09-307 217 A describes a method for correcting the position of elements in printed patterns.

The points mentioned above stand in the way of the increasingly higher performance requirements for such electronic components. Previous solutions focus on the use of new materials and printing processes. However, this is associated with disadvantages in processing, such as a limited number of layers when stacking. Furthermore, these components cannot equivalently replace the function of the ceramic multi-layer components.

It is therefore an object of the present invention to find a way of further improving the structuring of metal-containing layers, in particular with regard to structural accuracy.

This object is at least partially solved by the method disclosed in claim 1.

• - Aufbringen einer metallhaltigen Schicht, die eine Grobstruktur aufweist und ein pastöses Material umfasst, auf eine Oberfläche einer Keramikschicht, die eine Grünfolie umfasst. Die Hauptkomponenten des pastösen Materials sind ein oder mehrere Metalle und ein organisches Lösemittel.

The present invention discloses a method for the fine structuring of coarsely structured, pasty metal-containing layers. The procedure includes the following steps:

• - Application of a metal-containing layer which has a coarse structure and includes a pasty material on a surface of a ceramic layer which includes a green sheet. The main components of the pasty material are one or more metals and an organic solvent.

The roughly structured and pasty metal-containing layer can already have a defined structure. The metal-containing layer may form a continuous area on the surface or comprise several planar sections which lie within the same plane and have the same height but are not connected to one another. In one embodiment, the individual flat sections each have a length and a width of at least 50 μm.

The metal-containing layer comprises a pasty material containing one or more metals and an organic solvent as the main components. In addition, the metal-containing layer can contain a plastic powder.

The metals are in powder form in the form of metal grains that can be chemically or physically bonded.

Possible metals are, for example, copper or silver. For applications at high temperatures, Osram, for example, can be used as an alternative. The proportion of metal grains in the pasty metal-containing layer can be more than 70% of the volume of the layer. In one embodiment, the proportion of metal grains can be more than 83% by volume.

In addition to the metal-containing, powdery solid, the metal-containing layer contains an organic solvent, which gives the metal-containing layer its pasty property. In addition, the metal-containing layer can contain a plastic powder. The proportion of the organic solvent and the plastic powder in the pasty metal-containing layer can total 10% to 30% of the volume of the layer.

• - Scannen der Lage und Fläche der metallhaltigen Schicht und Generieren eines Datensatzes aus den erfassten Daten.

The organic solvent can form chemical or physical bonds to the metal grains. The processability of a paste that is to be applied or has already been applied can be adjusted with the type and viscosity of the solvent.

• - Scanning the position and area of the metal-bearing layer and generating a data set from the acquired data.

• - Auswerten des Datensatzes durch Vergleich mit vorgegebenen Werten.

The position and area of all sections of the metal-containing layer can be optically recorded using a suitable scanner and stored in a data set. A scanner can be used for this purpose, for example, which optically scans the entire surface covered with pasty, metal-containing material.

• - Evaluation of the data set by comparison with specified values.

• - Ermitteln kritischer Abschnitte der metallhaltigen Schicht, die von den vorgegebenen Werten abweichen.

The position and area of each section of the metal-containing layer can be determined from the data set obtained by scanning and compared with specified target values. With regard to the position, for example, a local or a global coordinate system can be defined for this. A global coordinate system assigns a coordinate to every point on the surface. A local coordinate system describes a position in relation to a selected fixed point within the surface, such as a fixed engineering structure. Such an arrangement can be an antenna, for example.

• - Determination of critical sections of the metal-containing layer that deviate from the specified values.

If the position and area of a section of the metal-containing layers do not match the specified target values, this section is designated as critical. Only those critical sections that exceed the given dimensions in terms of shape and area are taken into account in the present procedure.

If the dimensions of an area are too small, this cannot be corrected with the present method. In order to avoid dimensions that are too small, it is possible when applying the metal-containing layer to work with dimensions that slightly exceed the target values. The exact dimension can then be adjusted during the course of the procedure.

• - Zersetzen der kritischen Abschnitte per Laserbestrahlung in ein metallhaltiges Pulver, wobei die grobstrukturierte metallhaltige Schicht in eine gewünschte feinstrukturierte Schicht überführt wird und Sintern der Keramikschicht und der darauf aufgebrachten metallhaltigen Schicht nach erfolgter Feinstrukturierung.

If the position and/or area of a section is classified as critical by comparison with the target values, this section is recorded as critical and its position and area are saved in a critical data record.

• - Decomposition of the critical sections by laser irradiation into a metal-containing powder, the coarsely structured metal-containing layer being converted into a desired finely structured layer and sintering of the ceramic layer and the metal-containing layer applied thereto after fine structuring has taken place.

The area and position of the critical sections of the metalliferous layer are stored in the critical data set. A laser is aligned according to this critical data set and moved across the metal-containing layer so that it is aimed at and irradiates one of the critical sections. The pasty metal-containing layer within the critical section is transformed into a metal-containing layer by the laser irradiation powder decomposed. The reason for this is the heating of the metal-containing layer during prolonged irradiation. This leads to the volatilization of the organic solvent and the breaking of the bonds between the individual grains of the pasty metal-containing layer.

The pasty property of the metal-containing layer thus decreases and the metal-containing layer decomposes into a metal-containing powder. In the metal-containing powder, the individual metal grains and non-metal grains such as plastic grains hardly form any bonds with one another. If the metal-containing layer of a critical section has decomposed, the laser can be moved on and the next critical section can be irradiated.

In one embodiment, a plurality of lasers can be used simultaneously to speed up the method.

The method enables the shape and area of the sections of the metal-containing layer to be adapted to specified target values.

In this way, the dimensions of the individual sections of the metal-containing layer can be reduced and the layer can be converted into a finely structured metal-containing layer. In one embodiment, the dimension of a single section of the metal-containing layer can be reduced to less than 30 μm. In a preferred embodiment, the dimension of a single section can be reduced to less than 20 µm. The disclosed method thus enables an increased degree of fine structuring of the metal-containing layer.

Furthermore, positional inaccuracies of the sections of the metal-containing layer can be corrected by means of this method. If the distance between two current-carrying sections of the metal-containing layer is too small, capacitive and/or inductive interactions can occur, both of which are dependent on the distance between the sections. In addition, functional safety can be jeopardized by possible electrical flashovers or short circuits.

The same applies to a small distance between a current-carrying section of the metal-containing layer and a technical arrangement such as an antenna. If the distance is too small, interference signals can occur in the antenna.

For example, it is desirable that the distance between an integrated antenna and the metal-containing layer is the same size in each direction and is greater than a defined minimum distance.

By decomposing a critical section, the respective distance between the individual sections of a metal-containing layer or the distance to other technical arrangements can be increased.

The disclosed method thus enables an increased degree of accuracy in the fine structuring of the metal-containing layer.

As described, the metal-containing layer is applied to the surface of a ceramic layer.

The ceramic layer can comprise a ceramic whose main component can be aluminum oxide or zirconium oxide, for example. The ceramic layer can be cuboid and have a defined height and a defined base area. The base can have a square shape of a certain dimension. A typical dimension for a side length of the base of the ceramic layer can be more than 5 cm and less than 30 cm. A dimension for a side length can preferably be more than 10 cm and less than 25 cm. Even more preferably, the dimension for a side length is about 10 cm.

In one embodiment, the height of the ceramic layer in the sintered state can be between 10 μm and 1 mm. In a preferred embodiment, the height of the ceramic layer can be between 20 μm and 200 μm. In the non-sintered state, the height of the ceramic layer is approximately twice that.

If a section of the ceramic surface is irradiated with a laser during the process, the structure of the ceramic, unlike that of the metal-containing layer, does not change. The reason for this can be, for example, a high degree of radiation permeability, such as is exhibited by glass ceramics, or good thermal conductivity of the ceramic layer.

In one embodiment, the metal-containing layer can be printed onto the surface.

In a preferred embodiment, the metal-containing layer is screen printed onto the surface of the ceramic layer.

In screen printing, a metal or plastic screen is used as a stencil, and selected meshes of the screen are sealed with foil or paint. Ink is then printed through the open mesh of the screen onto a metal-containing layer that has previously been evenly applied to the ceramic layer. The ink protects the printed sections in the subsequent etching process, so that the printed sections of the metal-containing layer remain intact after etching. A large number of different metal-containing structures can thus be produced in parallel on the surface of the ceramic layer.

The ceramic layer includes a green sheet. This means that the ceramic layer is in an unsintered state.

This makes sense insofar as after the application of the pasty, metal-containing layer, a sintering step can be carried out to harden the metal-containing layer. In this way, the ceramic layer and the metal-containing layer can be sintered in one step.

The ceramic layer comprising the metal-containing layer applied thereto is sintered after fine structuring has taken place. During sintering, the ceramic and the metal are heated to a specific temperature and maintained so that a desired structure is created in the ceramic or in the metal.

The structure of the material influences properties such as hardness and durability of the material. During the sintering process, the organic solvent within the pasty metal-containing layer evaporates. The paste-like property of the metal-containing layer thus decreases and a solid, hardened metal-containing layer forms.

In one embodiment, a plurality of ceramic layers, each with metal-containing layers applied, are stacked to form a ceramic multi-layer component after fine structuring has taken place and before sintering. The component hardens and sinters together as a result of the subsequent sintering process.

In one embodiment, the metal-containing layer comprises portions of integrated electronic elements. The integrated electronic elements are electronic components that are formed from defined sections of one or more metal-containing layers.

A single portion of the metal-containing layer can be an integrated electronic element. On the other hand, an integrated electronic element may include multiple portions of the metal-containing layer or multiple metal-containing layers.

Sections that are in different metal-containing layers, but together form an integrated electronic element, can be connected by vias, i.e. electrical through-connections. The vias are contained in the ceramic layers arranged between the metal-containing layers.

An integrated electronic element can be, for example, a conductor track, a resistor, a coil, a capacitor or an electronic coupling.

To create integrated electronic devices that include portions of multiple metal-containing layers, multiple ceramic layers with metal-containing layers deposited thereon are stacked. For this purpose, the sections that belong together can be contacted via associated vias in the ceramic layers located between the ceramic layers. The sections that belong together in the various metal-containing layers and the associated vias in the ceramic layers can lie on top of one another. Contact points of the sections preferably lie precisely over associated vias. In this way, unwanted electrical losses can be minimized.

The disclosed method enables a higher degree of precision in the fine structuring of the metal-containing layers than prior art methods. The method thus enables the formation of cross-layer integrated electronic elements, between the individual sections of which there is a closed contact, so that undesirable electrical losses are minimized.

The precise placement of the individual portions of the integrated electronic elements further minimizes the misalignment of mating portions of the same integrated electronic elements in different layers, such as multiple turns of a coil. The low layer offset enables a high number of layers to be stacked.

In order to efficiently produce several components at the same time, ceramic layers of correspondingly large dimensions can be used in the production process, onto which sections of integrated electronic elements of several components can be applied. Several such ceramic layers can then be stacked. The resulting multilayer substrate can then be separated into individual multilayer components of smaller dimensions. The separation can be carried out e.g. by sawing.

The number of possible multilayer components that a multilayer substrate includes depends on the one hand on the fine structuring of the integrated electronic elements. This can be improved by the method described.

On the other hand, the number of multilayer components depends on the dimension of the multilayer substrate. With the use of larger ceramic layers, the positional inaccuracies of the integrated electronic element portions thereon increase. The method described allows these positional inaccuracies to be minimized and thus the production of comparatively larger ceramic layers.

In one embodiment, the metal-containing layer is scanned and the data set obtained during scanning is evaluated automatically by an automatic optical inspection system (AOI system).

By using an AOI system, the scanning process and the evaluation process can be automated and accelerated. Critical sections of the metal-containing layer can be registered more effectively, quickly and accurately. This also allows for a more accurate and effective use of the laser to irradiate and decompose the critical sections of the metal-containing layer.

In one embodiment, the metal-containing powder released by the laser irradiation is removed from the surface of the ceramic layer by suction. The metal-containing powder is formed during decomposition of the metal-containing layer by laser irradiation. The powder consists of a loose accumulation of individual metal grains that hardly form any bonds with one another. Furthermore, the powder can include plastic grains. The suction can be done with the help of a vacuum pump, for example.

In one embodiment, the metal-containing layer contains a non-metal-containing material such as a ceramic material as a secondary component. The non-metallic material is in the form of granules. A grain can contain both metal-bearing and non-metal-bearing material. Examples of non-metallic materials can be ceramics or glass ceramics and plastics.

If the pasty metal-containing layer is irradiated with a laser, the metal heats up. The rise in temperature leads to the volatilization of the organic solvent and the breaking of the bonds between the grains. The pasty property of the metal-containing layer thus decreases and the metal-containing layer decomposes into a metal-containing powder. In the metal-containing powder, the individual metal-containing and non-metal-containing grains hardly form any bonds with one another.

The invention also includes a ceramic multi-layer component which is manufactured using the method described. The multilayer component comprises a plurality of ceramic layers and finely structured, metal-containing layers arranged between them. The ceramic layers include vias that are used for electrical through-contacting. The metal-containing layers include sections of integrated electronic elements such as coils, couplings, capacitors or conductor tracks.

The ceramic layers and metal-containing layers are stacked on top of each other to form integrated electronic devices that span multiple layers. Contact surfaces of sections of integrated electronic elements that belong together in different metal-containing layers are electrically connected with a precise fit via an associated via.

For example, where an integrated electronic element is a coil, each metal-containing layer may comprise half a turn of the coil. Two metal-containing layers lying one on top of the other then cover an entire turn of the coil. Each section of the coil has contact pads on both ends. The contact areas can be applied to the vias with a precise fit using the disclosed method. The individual sections of the coil, which lie in different planes and thus in different metal-containing layers, can thus be connected by vias in the ceramic layers lying in between.

The minimum distance between two integrated electronic elements in the same metal-containing layer is less than 30 µm.

Thus, more integrated electronic elements can be applied to the surface of a ceramic layer than previously in the prior art. The smaller minimum distance between the integrated electronic elements is made possible by the disclosed method.

• 1 zeigt im Querschnitt ein keramisches Vielschichtbauteil, umfassend Keramikschichten, metallhaltige Schichten und integrierte elektronische Elemente.
• 2 zeigt in der Draufsicht eine beispielhafte Keramikschicht mit aufgebrachter, grobstrukturierter metallhaltiger Schicht.
• 3 zeigt in der Draufsicht die beispielhafte Keramikschicht mit aufgebrachter, feinstrukturierter metallhaltiger Schicht.
• 4 zeigt in der Draufsicht drei metallhaltige Schichten einer Ausführungsform eines Vielschichtbauteils mit integrierten elektronischen Elementen.
• 5 zeigt in der Draufsicht eine Ausführungsform einer Keramikschicht mit aufgebrachter, feinstrukturierter metallhaltiger Schicht.

Exemplary embodiments of the invention are to be explained in more detail below with reference to schematic figures. The invention is not limited to the disclosed embodiments. Identical or similar elements in the figures are provided with the same reference symbols.

• 1 shows in cross section a ceramic multi-layer component comprising ceramic layers, metal-containing layers and integrated electronic elements.
• 2 shows a plan view of an exemplary ceramic layer with an applied, coarsely structured, metal-containing layer.
• 3 shows a plan view of the exemplary ceramic layer with an applied, finely structured, metal-containing layer.
• 4 shows three metal-containing layers of an embodiment of a multi-layer component with integrated electronic elements in a plan view.
• 5 shows a plan view of an embodiment of a ceramic layer with an applied, finely structured, metal-containing layer.

1 12 shows an embodiment of a ceramic multilayer component 1 according to the present invention. The multilayer component 1 has a bottom 1A and a top 1B. The multi-layer component 1 comprises eight ceramic layers 2. A metal-containing layer 3 is applied to seven of these ceramic layers 2. Thus there is always a metal-containing layer 3 between every two ceramic layers 2. A ceramic layer 2 is present on the underside 1A and on the upper side 1B.

The multilayer component 1 was isolated from a multilayer substrate. The separation was made by sawing. The multilayer substrate can comprise a multiplicity of multilayer components 1 of the same dimensions and properties. The dimensions of a surface of a ceramic layer in the multi-layer substrate are between 20 cm and 25 cm in length and width. The height of a ceramic layer is approx. 50 µm in the unsintered state and approx. 25 µm after sintering.

The metal-containing layers 3 include integrated electronic elements 4. In 1 various examples of integrated electronic elements 4 are shown. In order to avoid undesired capacitive and/or inductive interactions, a minimum distance between the individual integrated electronic elements 4 is maintained.

An example of an integrated electronic element 4 is the coil 4A, which extends from the second-lowest to the fourth-lowest metal-containing layer of the multilayer component 1 with a total of 1.5 turns. Each of these layers comprises a section of the coil 4A which corresponds to half a turn. Ceramic layers 2 are present between the three sections of the coil 4A. The respective ends of the portions of the coil 4A have pads 5 thereon. The respectively corresponding contact points 5 are electrically contacted through the ceramic layer 2 by vias 6 .

Furthermore, the multilayer component 1 has two conductor tracks 4B in the second-lowest metal-containing layer 3 . The conductor tracks are applied to the bottom ceramic layer 2 at a distance of 30 μm.

In addition, the multi-layer component 1 includes other technical arrangements, such as an antenna 7. In order to avoid interference signals, a minimum distance between the integrated electronic elements 4 and the antenna 7 is maintained.

2 shows a plan view of an exemplary ceramic layer 2 of a multi-layer component 1, to which a pasty and coarsely structured metal-containing layer 3 is applied. The ceramic layer 2 comprises aluminum oxide, for example. The metal-containing layer 3 comprises a pasty material. The main component of this pasty material are silver grains. In addition, the pasty material includes a solvent and optionally an organic binder.

The metal-containing layer 3 comprises various integrated electronic elements 4. One of these integrated electronic elements 4 is the coil 4A. The exemplary metal-containing layer comprises a first portion of the coil 4A corresponding to three quarter turns. At the end of the section of the coil there is a contact point 5. The coil 4A is contacted with a via 6 here. The coil 4A is connected to a compact metal-containing layer 4C by means of a conductor track 4B.

Six antennas 7 are integrated in the ceramic layer 2 here. The antennas 7A and 7B lie within the compact layer 4C. In the present embodiment, for example, an antenna can be formed by a plurality of metal-containing vias arranged coaxially one above the other. The vias arranged coaxially one above the other result in an antenna which extends without gaps over a plurality of ceramic layers 2 and metal-containing layers 3 arranged one above the other. An antenna can extend over all layers of a multilayer component 1 and beyond.

The required minimum distance between these antennas 7A and 7B and the compact metal-containing layer 4C can be maintained.

The metal-containing layer 3 is applied to the ceramic layer 2 by screen printing. Due to the inadequacies of the printing process, sections of the metal-containing layer 3 are partially imprecisely applied to the ceramic layer 2 . Those sections whose dimensions deviate from the design values in terms of area and position are referred to as critical sections.

For example, the required minimum distances between the metal-containing layer 3 and the antennas 7A are not as shown here complied with. When current flows in the metal-containing layer 3, this can lead to interference signals and influence the impedance in the antennas 7A, for example.

Furthermore, the conductive line 4B cannot be printed as narrow as desired. The dimension of a conductor track that is applied by screen printing is limited to a minimum width of approx. 50 µm.

Also, the contact point 5 of the coil 4A does not exactly match the via 6. The reason for this is again the insufficient accuracy of the screen printing process. This positional inaccuracy of the contact point 5 can cause undesirable electrical losses.

3 12 shows the exemplary ceramic layer 2 2 with an applied metal-containing layer 3 after the metal-containing layer 3 has been finely structured by laser irradiation.

For this purpose, the roughly structured metal-containing surface 3 was scanned by an AOI system and the critical sections described above, the dimensions and positions of which deviate from the target values, were stored in a corresponding data set.

Then, the critical portions are irradiated with a laser so that the critical portions are heated. A laser with a suitable wavelength and power is selected for this purpose. For example, a laser with a wavelength between 900 nm and 1100 nm and a power between 4 W and 6 W is chosen. The spot diameter of the laser is preferably less than 30 μm.

The pasty material of the metal-containing layer 3 heats up as a result of the laser irradiation. This leads to the volatilization of the organic solvent. Furthermore, the physical or chemical bonds between the individual silver grains are broken. The pasty material thus decomposes into a silver powder.

The silver powder can then be sucked off the ceramic surface 2 .

Thus, the in 3 pictured fine structure preserved.

In this, the minimum distance between the antennas 7A and the compact surface 4C is now maintained by removing the respective critical sections of the compact surface 4C. This leads to a decrease in electrical interactions and the resulting interference signals.

The conductor line 4B has been shrunk to a width of, for example, 30 μm by means of laser irradiation. Smaller dimensions allow a higher number of circuit traces on a ceramic surface of the same size. The performance of a multi-layer component 1 constructed from such ceramic layers 2 can thus be increased.

The contact point 5 has been made precise by means of laser irradiation. The contact point now overlaps the Via 6 with an almost perfect fit. This leads to a reduction in unwanted electrical losses.

A multi-layer component can be stacked from a plurality of ceramic layers 2 with printed metal-containing layers 3 after the fine structuring has taken place and has been described. The stacking is carried out in such a way that contact points 5 of sections of respectively associated integrated electronic elements 4 are positioned as precisely as possible over associated vias 6 in order to avoid electrical losses. A via 6 makes contact in each case with two contact points 5 of sections of an integrated electronic element 4 that belong together, through a ceramic layer 2 .

4 FIG. 1 schematically shows a multilayer component 1 of an embodiment in a plan view. In the example shown, three ceramic layers 2, which are each printed with metal-containing layers 3A, 3B and 3C, are stacked one on top of the other. Only the ceramic layer 2 on which the bottom metal-containing layer 3C is based is shown. The overlying ceramic layers 2 have been neglected for reasons of better clarity. The metal-containing layers 3A to 3C of the illustrated multi-layer component 1 were applied to the respective ceramic layer 2 by means of a screen printing process.

The illustrated multilayer device 1 includes various integrated electronic elements, such as a coil 4A and vias 4D, which comprise sections in a plurality of layers 3 containing metal. In 4 three metal-containing layers 3A, 3B and 3C, which lie on top of one another, are shown by way of example.

Due to the positional inaccuracies of the screen printing process, the sections that belong together are offset in the various metal-containing layers 3 . This layer offset leads to undesirable electrical losses and interference effects. When a large number of metal-containing layers are stacked on top of one another, such position errors can multiply and significantly limit the function of the multi-layer component. This is particularly at the vias 4D, which are all slightly offset from one another in the individual metal-containing layers and are therefore no longer arranged or aligned with an exact fit one above the other.

With the aid of the method disclosed, it is possible to minimize positional inaccuracies and the resulting layer offset of sections of the same integrated electronic components 4 . Undesirable electrical losses and interference effects can thus also be reduced.

5 12 shows a further embodiment of a ceramic layer 2 of a multi-layer component 1. A metal-containing layer 3 is in turn applied to the ceramic layer 2. FIG. The metal-containing layer 3 includes integrated electronic elements 4. This includes the conductor track 4E. In the present example, the conductor track 4E is characterized in that it has a width of 30 μm on its narrow side. This width was achieved using the disclosed method.

For this purpose, the metal-containing material was removed from a large-area, compact, metal-containing layer 4C by means of a laser along two tracks 8. For this purpose, the metal-containing layer 4C in the area of the tracks 8 was decomposed by irradiation with a laser and the resulting powder was then sucked off. The two adjacent tracks 8 are arranged in parallel, with the distance between the two nearest edges of the two tracks being only 30 μm. The metal-containing strip 4E remaining between the two tracks 8 functions as a conductor track, the small width of which, here of 30 μm, could not only be produced with the imprinting method but only with the method according to the invention.

Reference List

1

multilayer component

1A

Underside of the multi-layer component 1

1B

Top of the multi-layer component 1

2

ceramic layer

3

metal-containing layer

4

integrated electronic element

4A

Kitchen sink

4B,E

traces

4C

compact metal-containing layer

4D

via

5

contact point

6

Via

7

antenna

7A,B

Antennas within the compact layer 4C

8th

Web free of metal-containing layer 3

Claims (8)

Method for the fine structuring of coarsely structured, pasty, metal-containing layers (3), comprising the following steps: - Application of a metal-containing layer (3), which has a coarse structure and includes a pasty material whose main components are one or more metals and an organic solvent, on a surface of a ceramic layer (2) which includes a green film, - Scanning the position and area of the metal-containing layer (3) and generating a data set from the recorded data, - Evaluation of the data set by comparison with specified values, - Determining critical sections of the metal-containing layer (3) that deviate from the specified values, - decomposing the critical sections by laser irradiation into a metal-containing powder, the coarsely structured metal-containing layer (3) being converted into a desired finely structured layer (3), - Sintering of the ceramic layer (2) and the metal-containing layer (3) applied thereto after fine structuring has taken place. procedure after claim 1 , wherein the metal-containing layer (3) is applied to the surface of the ceramic layer (2) by screen printing. Procedure according to one of Claims 1 or 2 , wherein a plurality of ceramic layers (2) with applied layers (3) containing metal are stacked after fine structuring and before sintering to form a ceramic multi-layer component (1). Procedure according to one of Claims 1 until 3 , wherein the metal-containing layer (3) comprises sections of integrated electronic elements (4). Procedure according to one of Claims 1 until 4 , whereby the scanning and the evaluation of the data set obtained are carried out automatically by an automatic optical inspection system (AOI system). Procedure according to one of Claims 1 until 5 , wherein the metal-containing powder is removed by suction from the surface of the ceramic layer (2). Procedure according to one of Claims 1 until 6 , The metal-containing layer (3) as a by-come component non-metallic materials, in particular ceramic materials, includes. Ceramic multi-layer component (1), which according to a method according to one of Claims 1 until 7 and which comprises a plurality of ceramic layers (2) and finely structured, metal-containing layers (3) arranged between them, wherein: - the ceramic layers (2) comprise vias (6) for electrical through-connection, - the metal-containing layers (3) comprise sections of integrated electronic elements (4) and - the ceramic layers (2) and the metal-containing layers (3) are stacked one on top of the other in such a way that integrated electronic elements (4) which extend over a number of metal-containing layers (3) are formed, wherein - contact surfaces ( 5) associated sections of integrated electronic elements (4) in different metal-containing layers (3) are electrically connected with a precise fit via an associated via (6), and - the minimum distance between two integrated electronic elements (4) in the same metal-containing layer (3) is less than is 30 µm.

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