EP1530654A2 - Method for electroplating of contact layers on ceramic components - Google Patents
Method for electroplating of contact layers on ceramic componentsInfo
- Publication number
- EP1530654A2 EP1530654A2 EP02754511A EP02754511A EP1530654A2 EP 1530654 A2 EP1530654 A2 EP 1530654A2 EP 02754511 A EP02754511 A EP 02754511A EP 02754511 A EP02754511 A EP 02754511A EP 1530654 A2 EP1530654 A2 EP 1530654A2
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- ceramic components
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- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/48—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on zirconium or hafnium oxides, zirconates, zircon or hafnates
- C04B35/49—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on zirconium or hafnium oxides, zirconates, zircon or hafnates containing also titanium oxides or titanates
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- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
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- C04B35/00—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products
- C04B35/01—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics
- C04B35/46—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on titanium oxides or titanates
- C04B35/462—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on titanium oxides or titanates based on titanates
- C04B35/465—Shaped ceramic products characterised by their composition; Ceramics compositions; Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on oxide ceramics based on titanium oxides or titanates based on titanates based on alkaline earth metal titanates
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- C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
- C04B41/009—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone characterised by the material treated
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- C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
- C04B41/45—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements
- C04B41/4505—Coating or impregnating, e.g. injection in masonry, partial coating of green or fired ceramics, organic coating compositions for adhering together two concrete elements characterised by the method of application
- C04B41/4564—Electrolytic or electrophoretic processes, e.g. electrochemical re-alkalisation of reinforced concrete
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- C04B41/00—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone
- C04B41/80—After-treatment of mortars, concrete, artificial stone or ceramics; Treatment of natural stone of only ceramics
- C04B41/81—Coating or impregnation
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- C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
- C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
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- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3205—Alkaline earth oxides or oxide forming salts thereof, e.g. beryllium oxide
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- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3205—Alkaline earth oxides or oxide forming salts thereof, e.g. beryllium oxide
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- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3224—Rare earth oxide or oxide forming salts thereof, e.g. scandium oxide
- C04B2235/3227—Lanthanum oxide or oxide-forming salts thereof
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- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/3231—Refractory metal oxides, their mixed metal oxides, or oxide-forming salts thereof
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- C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
- C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
- C04B2235/30—Constituents and secondary phases not being of a fibrous nature
- C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
- C04B2235/327—Iron group oxides, their mixed metal oxides, or oxide-forming salts thereof
- C04B2235/3275—Cobalt oxides, cobaltates or cobaltites or oxide forming salts thereof, e.g. bismuth cobaltate, zinc cobaltite
Definitions
- the invention relates to a method for producing a well-adhering electroplating of ceramic materials.
- Contact surfaces are then wires, e.g. applied in a soldering process.
- the adhesive strength of the contact surfaces on the ceramic component plays an important role. On an untreated ceramic surface, it is usually so low that it does not meet the requirements of practice. Various methods have therefore been described to achieve better adhesive strengths by pretreating the ceramic components before applying the contact surfaces.
- a basic contact is normally applied, for example, by dipping the component in metallizing paste or in conductive adhesive. This basic contact is then dried and usually baked. Due to the oxidative conditions during baking, almost all metallization pastes or conductive adhesives contain precious metals such as silver, palladium or platinum. The basic contact then enables the galvanic application of further metal layers, for example consisting of nickel or tin. The outermost layer, usually tin, is used for the necessary wettability of the component with solder when soldering. responsive and thus determines the component's SMD capability.
- the disadvantage of applying a base contact by means of a metallization paste is that large amounts of precious metals have to be used and at the same time a time-consuming and energy-intensive baking of the base contact is necessary.
- DE 36 32 513 A1 discloses a process in which the ceramic base bodies are pretreated first by the action of gaseous boron halides on the ceramic surface in a glow discharge zone and by subsequent immersion in alkaline or acidic aqueous solutions. After further treatment with a metal salt solution, a contacting layer can be galvanically deposited on the ceramic component. This process is also very time and energy consuming and usually also requires precious metal salt solutions.
- the object of the invention is therefore to enable direct galvanic deposition of a contacting layer on the ceramic components by simple pretreatment of the ceramic components.
- the invention describes a method in which a simple mechanical and chemical treatment of the areas of the ceramic component to be electroplated with a phosphoric acid, aqueous solution with a pH of about 1.0 to 1.5 increases the adhesive strength for contact layers can be achieved.
- the contact layers can then be applied directly to the areas previously activated with the solution by means of a galvanic process.
- Direct electroplating in the sense of the invention is understood to be to galvanically deposit a contact layer immediately after the mechanical and chemical pretreatment of the areas to be electroplated, without further additional time-consuming and cost-intensive process steps, for example using electroless processes based on tin chloride-palladium chloride solutions to create a catalytic seed layer.
- the ceramic components can advantageously be washed in order to remove the chemical solutions.
- the surfaces of the ceramic base body to be electroplated are advantageously treated during a process step A) by mechanical roughening and by chemical etching in the above-mentioned acidic aqueous solution.
- the roughening can be accomplished, for example, by the fact that grinding bodies act on the areas of the components to be galvanized. Small balls or cubes made of SiC, corundum or steel, for example, can be used as grinding wheels.
- Process step A can advantageously be implemented by rolling friction in a mixture of ceramic components and grinding wheels in an acidic, aqueous medium in a rotating drum. Due to the simultaneous mechanical roughening and the chemical etching, the surfaces of the ceramic component can be modified reliably so that a good adhesive strength of the contact surfaces on the ceramic component can be guaranteed during the galvanizing process in process step B).
- High-resistance materials such as barium titanate, aluminum oxide or glass are suitable for the passivation layer.
- divalent metal MII is either strontium or
- Barium and the trivalent metal MIII is a rare earth element where:
- the passivation layer can also comprise, for example, a lead-lanthanum-zirconium-titanate ceramic (PLZT ceramic) of the formula (Pb, La) (Zr, Ti) Ü3.
- Pb, La lead-lanthanum-zirconium-titanate ceramic
- Ü3 lead-lanthanum-zirconium-titanate ceramic
- Pb, La lead-lanthanum-zirconium-titanate ceramic
- Ü3 lead-lanthanum-zirconium-titanate ceramic
- PbO ceramic lead-lanthanum-zirconium-titanate ceramic
- These ceramics are advantageously composed of PbO with an approximate proportion of 50-80% by weight, ZrO2 with approximately 20-50% by weight, Ti 0 3 with approximately 10-40% by weight and La0 3 with approximately 0-20% by weight.
- a contact layer is then electrodeposited onto the areas of the component which are roughened and etched in method step A).
- the electroplating is advantageously carried out in the bulk material, the components being mixed with contact bodies in an acidic metal salt solution.
- the contact bodies are advantageously electrically conductive metal balls, for example steel balls, which contact the components and ensure better current flow between the components, so that a higher deposition rate of the metal (contact layer) on the components can be achieved.
- the component-contact body mixture is in a rotating drum in an electrolyte solution, the drum being in a galvanic basin.
- a contact layer can be galvanically deposited on the areas of the components which have been pretreated according to process step A).
- FIGS. 1A and 1B show process steps A) and B) of the process according to the invention.
- FIGS. 2A and 2B show a cross section and a perspective view through a ceramic component produced by the method according to the invention with a continuous passivation layer on the lateral surfaces, with further galvanic layers then being applied using conventional methods.
- FIGS. 3A and 3B show a cross section and a perspective view of a ceramic component produced by the method according to the invention with also further metallization layers applied by conventional methods, the passivation layer leaving free the areas of the lateral surfaces adjoining the end faces.
- the areas of the ceramic component 1 which are not to be galvanized are provided with a passivation layer made of ZnMn2Ü4, for example, in method step AI) before the method according to the invention.
- the ceramic components 1 with the passivation layers 2 are brought into contact with grinding bodies 5 in an acidic, aqueous solution (process step A).
- the mixture of grinding wheels and ceramic components is located in a rotating drum 10 which is immersed in an acid bath 15.
- the rotating movement of the drum is shown by an arrow in Figure 1A.
- the axis of rotation of the drum is inclined in order to ensure a rolling movement of the mixture of ceramic components and grinding wheels. Due to the simultaneous mechanical roughening by the grinding bodies 5 and the chemical etching in the acid bath 15, the areas 3 of the components 1 to be galvanized are modified in such a way that a reliable casual adhesion of the galvanically applied contact layers becomes possible.
- a phosphoric acid, aqueous solution with a pH of about 1.0 to 1.5 is used as the acid bath.
- the contact areas and the contacting probability between the grinding wheels and the ceramic components are increased by maintaining an advantageous ratio of component length to grinding wheel diameter. This is advantageously about 1: 0.05 to 1: 0.8.
- the entire arrangement with the rotating drum 10 and the grinding device component mixture is located in a basin 20 together with the acid bath.
- the ceramic components pretreated according to A) are galvanized in the bulk material (see also FIG. IB).
- a mixture of components 1 with a passivation layer 2 and contact bodies 25 is brought into a rotating drum 10.
- This drum is immersed in an electrolyte solution 30, which is located in an electroplating basin 35.
- the electrolytic solution consists, for example, of a tin-salt solution with an approximate concentration of 10 to 20 g SnII / liter, the pH being approximately 3 to 4.5.
- Electrically conductive balls for example steel balls, are preferably used as contact bodies.
- the electroplating basin 35 is switched as an anode and at the same time an electrode 36 is immersed in the rotating drum 10, which is connected as a cathode.
- the rolling movement of the drum 10 enables good contact between the components and the contact bodies, the ratio of component length to contact body diameter preferably being in the range from about 1: 0.05 to 1: 0.08 in the method according to the invention. This increases the contact probability between the contact bodies and the components, so that a good deposition of the metal on the regions 3 is possible due to the good current flow.
- the Current densities are preferably in the range from 0.05 to 0.15 A / dm 2 .
- the contact bodies used in B) are preferably also used simultaneously as grinding bodies in process step A). This enables a simple and continuous process, in which after the process step A) the rotating drum is removed from the acid bath 15, washed several times with water, in order to avoid contamination of the acid bath on the components or contact or grinding wheels in the process step B) to convict. After washing, the component / contact body mixture can be immersed directly in the electroplating bath with the electrolyte solution 35 and process step B) can be carried out. As a result, additional complex work steps, such as, for example, removing the grinding wheels during the transition from process steps A) to B) can be avoided.
- the advantages of the present variant of the method according to the invention also consist in the fact that both the pretreatment of the areas 3 to be galvanized in method step A) and method step B) can be carried out with the same technical devices provided for the galvanizing. There is no longer any need for cumbersome baking processes for metal conductive pastes or additional insertion of the components in glow discharge zones.
- FIGS. 2A and 2B show a component 1 (varistor) produced by the method according to the invention with internal electrodes 55, which contact the contact layers 40, in cross section and in perspective view.
- the passivation layer 2 which completely covers the lateral surfaces of the component and which was applied in method step AI), is located on the component.
- the contact layer 50 generally consists of tin and determines the soldering properties of the ceramic component. In this case, the contact layers only cover the end faces of the component.
- FIGS. 3A and 3B show a component, a varistor, produced by the method according to the invention, also in cross section and in a perspective view. It can be seen that in this case, after the process step AI), a passivation layer 2 is present, which only covers parts of the lateral surfaces of the component, while the end faces and regions of the lateral surfaces adjacent to the end faces are left free. Inside the component there are internal electrodes 55 which contact the contact layers 40 applied by the method according to the invention in B). Further contact layers 45 and 50 can be applied using conventional galvanic processes. In this case, the contact layers cover the end faces and the regions of the lateral surfaces of the component which are adjacent thereto.
- the method according to the invention is not limited to the exemplary embodiment presented here. Further variations are possible with regard to the chemical and mechanical pretreatment of the components as well as with regard to the electrolyte solutions and grinding media used, as well as contact bodies. With the method according to the invention, contact layers can be applied directly to a whole series of ceramic components, for example varistors or thermistors, or other ceramic components.
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- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
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- Electrochemistry (AREA)
- Composite Materials (AREA)
- Electroplating Methods And Accessories (AREA)
- Other Surface Treatments For Metallic Materials (AREA)
Abstract
The invention concerns a method for electroplating of contact layers on electroceramic components (1). The mechanical and chemical treatment of the zones to be galvanized (3) of an electroceramic component (1) whereof the zones not to be galvanized have been previously covered with a passivating layer (2) enhances adherence of the contact layers on the zones to be galvanized (3). The chemical and mechanical treatment is based on the use of a chemical bath (15) consisting of an aqueous phosphoric acid solution wherein are present abrasive bodies which act on the electroceramic components.
Description
Beschreibungdescription
Verfahren zum galvanischen Aufbringen von Kontaktschichten auf keramische BauelementeProcess for the galvanic application of contact layers on ceramic components
Die Erfindung betrifft ein Verfahren zur Erzeugung einer gut haftenden Galvanisierung von keramischen Materialien.The invention relates to a method for producing a well-adhering electroplating of ceramic materials.
Viele elektrokeramische Bauelemente werden üblicherweise in Oberflächenmontage auf Platinen gelötet. Die Möglichkeit der Oberflächenmontage (SMD-Fähigkeit ) kann dadurch erreicht werden, daß Kontaktflächen auf den keramischen Bauelementen angebracht werden. Gleiches gilt für die Herstellung bedrahte- ter Bauelemente. Auch hier müssen zunächst Kontaktflächen auf dem keramischen Bauelement aufgebracht werden. Auf diesenMany electro-ceramic components are usually soldered on boards in surface mounting. The possibility of surface mounting (SMD capability) can be achieved by attaching contact surfaces to the ceramic components. The same applies to the manufacture of wired components. Here too, contact surfaces must first be applied to the ceramic component. On this
Kontaktflächen werden dann Drähte, z.B. in einem Lötverfahren aufgebracht .Contact surfaces are then wires, e.g. applied in a soldering process.
Die Haftfestigkeit der Kontaktierungsflachen auf dem kerami- sehen Bauelement spielt eine wesentliche Rolle. Auf einer un- behandelten Keramikoberfläche ist sie in der Regel so gering, daß sie den Anforderungen der Praxis nicht genügt. Es sind deshalb verschiedene Methoden beschrieben worden, durch eine Vorbehandlung der keramischen Bauteile vor dem Aufbringen der Kontaktflächen bessere Haftfestigkeiten zu erzielen.The adhesive strength of the contact surfaces on the ceramic component plays an important role. On an untreated ceramic surface, it is usually so low that it does not meet the requirements of practice. Various methods have therefore been described to achieve better adhesive strengths by pretreating the ceramic components before applying the contact surfaces.
Normalerweise wird eine Grundkontaktierung zum Beispiel durch Tauchen des Bauteils in Metallisierungspaste oder in Leitkleber aufgebracht. Diese Grundkontaktierung wird anschließend getrocknet und in der Regel eingebrannt. Aufgrund der oxida- tiven Bedingungen während des Einbrennens enthalten fast alle Metallisierungspasten oder Leitkleber Edelmetalle, wie zum Beispiel Silber, Palladium oder Platin. Die Grundkontaktie- rung ermöglicht anschließend das galvanische Aufbringen wei- terer Metallschichten, zum Beispiel bestehend aus Nickel oder Zinn. Die äußerste Schicht, in der Regel Zinn, ist für die notwendige Benetzbarkeit des Bauteils mit Lot beim Löten ver-
antwortlich und bestimmt somit die SMD-Fähigkeit des Bauelements. Der Nachteil beim Aufbringen einer Grundkontaktierung mittels einer Metallisierungspaste besteht darin, daß große Mengen Edelmetalle eingesetzt werden müssen und zugleich ein zeit- und energieaufwendiges Einbrennen der Grundkontaktierung nötig ist.A basic contact is normally applied, for example, by dipping the component in metallizing paste or in conductive adhesive. This basic contact is then dried and usually baked. Due to the oxidative conditions during baking, almost all metallization pastes or conductive adhesives contain precious metals such as silver, palladium or platinum. The basic contact then enables the galvanic application of further metal layers, for example consisting of nickel or tin. The outermost layer, usually tin, is used for the necessary wettability of the component with solder when soldering. responsive and thus determines the component's SMD capability. The disadvantage of applying a base contact by means of a metallization paste is that large amounts of precious metals have to be used and at the same time a time-consuming and energy-intensive baking of the base contact is necessary.
In der Druckschrift DE 36 32 513 AI ist ein Verfahren offenbart, bei dem die keramischen Grundkörper zuerst durch Ein- Wirkung von gasförmigen Borhalogeniden auf die Keramikoberfläche in einer Glimmentladungszone und durch anschließendes Eintauchen in alkalische oder saure wässrige Lösungen vorbehandelt werden. Nach weiterer Behandlung mit einer Metall - Salzlösung kann galvanisch eine Kontaktierungsschicht auf dem keramischen Bauelement abgeschieden werden. Dieses Verfahren ist ebenfalls sehr zeit- und energieaufwendig und erfordert in der Regel ebenfalls Edelmetallsalzlösungen.DE 36 32 513 A1 discloses a process in which the ceramic base bodies are pretreated first by the action of gaseous boron halides on the ceramic surface in a glow discharge zone and by subsequent immersion in alkaline or acidic aqueous solutions. After further treatment with a metal salt solution, a contacting layer can be galvanically deposited on the ceramic component. This process is also very time and energy consuming and usually also requires precious metal salt solutions.
Der Erfindung liegt deshalb die Aufgabe zugrunde, durch eine einfache Vorbehandlung der keramischen Bauelemente eine direkte galvanische Abscheidung einer Kontaktierungsschicht auf den keramischen Bauteilen zu ermöglichen.The object of the invention is therefore to enable direct galvanic deposition of a contacting layer on the ceramic components by simple pretreatment of the ceramic components.
Die Aufgabe wird durch die Merkmale des Anspruchs 1 gelöst . Vorteilhafte Ausgestaltungen sind Gegenstand weiterer Ansprüche .The object is solved by the features of claim 1. Advantageous refinements are the subject of further claims.
Die Erfindung beschreibt ein Verfahren, bei dem durch eine einfache mechanische und chemische Behandlung der zu galvani- sierenden Bereiche des keramischen Bauelements mit einer phosphorsauren, wässrigen Lösung mit einem pH-Wert von etwa 1,0 bis 1,5, eine erhöhte Haftfestigkeit für Kontaktschichten erreicht werden kann. In einem zweiten Schritt können dann mittels eines galvanischen Prozesses auf die zuvor mit der Lösung aktivierten Bereiche direkt die Kontaktschichten aufgebracht werden.
Unter direkter Galvanisierung im Sinne der Erfindung wird verstanden, sofort nach der mechanischen und chemischen Vorbehandlung der zu galvanisierenden Bereiche galvanisch eine Kontaktschicht abzuscheiden, ohne vorher noch mit weiteren zusätzlichen zeit- und kostenintensiven Verfahrenschritten z.B. mittels stromloser Verfahren auf der Basis von Zinnchlorid-Palladiumchlorid-Lösungen, eine katalytische Keimschicht zu erzeugen. Nach der mechanischen und chemischen Vorbehand- lung können die keramischen Bauelemente vorteilhafterweise gewaschen werden, um die chemischen Lösungen zu entfernen.The invention describes a method in which a simple mechanical and chemical treatment of the areas of the ceramic component to be electroplated with a phosphoric acid, aqueous solution with a pH of about 1.0 to 1.5 increases the adhesive strength for contact layers can be achieved. In a second step, the contact layers can then be applied directly to the areas previously activated with the solution by means of a galvanic process. Direct electroplating in the sense of the invention is understood to be to galvanically deposit a contact layer immediately after the mechanical and chemical pretreatment of the areas to be electroplated, without further additional time-consuming and cost-intensive process steps, for example using electroless processes based on tin chloride-palladium chloride solutions to create a catalytic seed layer. After the mechanical and chemical pretreatment, the ceramic components can advantageously be washed in order to remove the chemical solutions.
Vorteilhafterweise werden die zu galvanisierenden Flächen des keramischen Grundkörpers während eines Verfahrensschrittes A) durch mechanisches Aufrauhen und durch chemisches Ätzen in der oben genannten sauren wässrigen Lösung behandelt . Das Aufrauhen läßt sich beispielsweise dadurch bewerkstelligen, daß auf die zu galvanisierenden Bereiche der Bauelemente Schleifkörper einwirken. Als Schleifkörper lassen sich bei- spielsweise kleine Kugeln oder auch Würfel verwenden, die aus SiC, Korund oder Stahl bestehen. Der Verfahrensschritt A läßt sich vorteilhafterweise durch eine abrollende Reibung in einem Gemenges aus keramischen Bauteilen und Schleifkörpern in einem sauren, wässrigen Medium in einer rotierenden Trommel realisieren. Durch das gleichzeitige mechanische Aufrauhen und das chemische Ätzen lassen sich die Oberflächen des keramischen Bauteils zuverlässig so modifizieren, daß eine gute Haftfestigkeit der Kontaktflächen auf dem keramischen Bauelement während des Galvanisierungsprozesses im Verfahrens- schritt B) gewährleistet werden kann.The surfaces of the ceramic base body to be electroplated are advantageously treated during a process step A) by mechanical roughening and by chemical etching in the above-mentioned acidic aqueous solution. The roughening can be accomplished, for example, by the fact that grinding bodies act on the areas of the components to be galvanized. Small balls or cubes made of SiC, corundum or steel, for example, can be used as grinding wheels. Process step A can advantageously be implemented by rolling friction in a mixture of ceramic components and grinding wheels in an acidic, aqueous medium in a rotating drum. Due to the simultaneous mechanical roughening and the chemical etching, the surfaces of the ceramic component can be modified reliably so that a good adhesive strength of the contact surfaces on the ceramic component can be guaranteed during the galvanizing process in process step B).
Um zu erreichen, daß nur selektiv die zu galvanisierenden Bereiche des Bauteils vorbehandelt werden, ist es möglich, die Bauteile auf einem Hilfsträger zu befestigen und nur diejeni- gen Bereiche, die galvanisiert werden sollen, in das chemische Bad einzutauchen, das die Schleifkörper enthält.
Es ist auch möglich, die Bauelemente im Verfahrensschritt A) als Schüttgut einzusetzen und das Verfahren mit dem Schüttgut durchzuführen, wobei die keramischen Bauelemente in diesem Fall vollständig in das chemische Bad eintauchen, das die Schleifkörper enthält. Deshalb es ist in diesem Fall empfehlenswert, vorher in einem Verfahrensschritt AI) die nicht zu galvanisierenden Bereiche des keramischen Bauelements mit einer Passivierungsschicht zu versehen, die diese Bereiche vor der Einwirkung des chemischen Bades und der Schleifkörper schützt.In order to ensure that the areas of the component to be electroplated are only selectively pretreated, it is possible to fasten the components on an auxiliary carrier and to immerse only those areas which are to be electroplated in the chemical bath which contains the grinding wheels. It is also possible to use the components in process step A) as bulk material and to carry out the method with the bulk material, in which case the ceramic components are completely immersed in the chemical bath which contains the grinding wheels. It is therefore advisable in this case to provide the areas of the ceramic component that are not to be galvanized with a passivation layer beforehand in a process step AI), which protects these areas from the action of the chemical bath and the grinding wheels.
Für die Passivierungsschicht in Frage kommen beispielsweise hochohmige Materialien, wie Bariumtitanat , Aluminiumoxid oder Glas. Auch die Verwendung von Spinellen der allgemeinen For- mel AB2O4 , wobei A zweiwertige Metalle und B drei- oder vierwertige Metalle, zum Beispiel ZnMn2Ü4 darstellt, ist vorteilhaft. Möglich ist auch das Aufbringen von Schutzumhüllungen und Laminaten, wie sie in der Patentschrift DE 196 34 498 offenbart sind, auf die hier voll inhaltlich Bezug genommen wird. Möglich ist auch die Verwendung von Perowskiten der folgenden allgemeinen FormelHigh-resistance materials such as barium titanate, aluminum oxide or glass are suitable for the passivation layer. The use of spinels of the general formula AB2O4, where A is divalent metals and B is trivalent or tetravalent metals, for example ZnMn2Ü4, is also advantageous. It is also possible to apply protective coverings and laminates, as disclosed in patent specification DE 196 34 498, to which reference is made in full here. Perovskites of the following general formula can also be used
MlIχMlII1_xTiI χ+ycoI yCoIII1.x_2y03,MlI χ MlII 1 _ x TiI χ + y coI y CoIII 1 . x _2y0 3 ,
bei der das zweiwertige Metall MII entweder Strontium oderwhere the divalent metal MII is either strontium or
Barium und das dreiwertige Metall MIII ein Element der seltenen Erden ist, bei der gilt:Barium and the trivalent metal MIII is a rare earth element where:
0 < x < 0,85; 0 < y < (l-x)/2 und x+y < 1.0 <x <0.85; 0 <y <(l-x) / 2 and x + y <1.
Die Passivierungsschicht kann beispielsweise auch eine Blei- Lanthan-Zirkon-Titanatkeramik (PLZT-Keramik) der Formel (Pb,La) (Zr,Ti)Ü3 umfassen. Dabei handelt es sich um polykristalline Keramiken mit Perowskit-Struktur, die durch die all- gemeine Formel ABO3 gekennzeichnet sind. Die A-Plätze können dabei von Pb besetzt sein, das teilweise von La ersetzt werden kann, wobei die B-Plätze von Zr oder Ti besetzt sein kön-
nen. Vorteilhafterweise setzen sich diese Keramiken aus PbO mit einem ungefähren Anteil von 50-80 Gewichts%, Zrθ2 mit etwa 20-50 Gewichts%, Ti 03 mit etwa 10-40 Gewichts% und La03 mit etwa 0-20 Gewichts% zusammen.The passivation layer can also comprise, for example, a lead-lanthanum-zirconium-titanate ceramic (PLZT ceramic) of the formula (Pb, La) (Zr, Ti) Ü3. These are polycrystalline ceramics with a perovskite structure, which are characterized by the general formula ABO3. The A positions can be occupied by Pb, which can be partially replaced by La, and the B positions can be occupied by Zr or Ti. NEN. These ceramics are advantageously composed of PbO with an approximate proportion of 50-80% by weight, ZrO2 with approximately 20-50% by weight, Ti 0 3 with approximately 10-40% by weight and La0 3 with approximately 0-20% by weight.
Diese Materialien sind vorteilhafterweise hochohmig, mechanisch sehr beständig und gleichzeitig unempfindlich gegen die sauren wässrigen Lösungen, die zum Ätzen bzw. zur aktivierenden Behandlung eingesetzt werden und behindern aufgrund ihrer Hochohmigkeit im Verfahrensschritt B) das galvanische Abscheiden einer Kontaktschicht auf den nicht zu galvanisierenden Bereichen des Bauelements.These materials are advantageously high-resistance, mechanically very resistant and at the same time insensitive to the acidic aqueous solutions used for the etching or activating treatment and, because of their high impedance in process step B), hinder the galvanic deposition of a contact layer on the areas of the component that are not to be galvanized ,
Im Verfahrensschritt B) wird anschließend auf die im Verfah- rensschritt A) aufgerauhten und geätzten Bereiche des Bauelements galvanisch eine Kontaktschicht abgeschieden. Die Galvanisierung erfolgt vorteilhafterweise im Schüttgut, wobei die Bauteile in einer sauren Metallsalzlösung mit Kontaktkörpern vermengt werden. Die Kontaktkörper sind vorteilhafterweise elektrisch leitende Metallkugeln, beispielsweise Stahlkugeln, die die Bauelemente kontaktieren und einen besseren Stromfluß zwischen den Bauelementen gewährleisten, so daß eine höhere Abscheidungsrate des Metalls (Kontaktschicht) auf den Bauelementen erzielt werden kann. In der Regel befindet sich das Bauelement -Kontaktkörper-Gemenge in einer rotierenden Trommel in einer Elektrolytlösung, wobei die Trommel sich in einem Galvanikbecken befindet. Durch Anlegen eines geeigneten Stromes (Galvanikbecken beispielsweise als Anode geschaltet und eine Kathode, die in die rotierende Trommel eintaucht) läßt sich galvanisch eine Kontaktschicht auf den nach Verfahrensschritt A) vorbehandelten Bereichen der Bauelemente abscheiden.In method step B), a contact layer is then electrodeposited onto the areas of the component which are roughened and etched in method step A). The electroplating is advantageously carried out in the bulk material, the components being mixed with contact bodies in an acidic metal salt solution. The contact bodies are advantageously electrically conductive metal balls, for example steel balls, which contact the components and ensure better current flow between the components, so that a higher deposition rate of the metal (contact layer) on the components can be achieved. As a rule, the component-contact body mixture is in a rotating drum in an electrolyte solution, the drum being in a galvanic basin. By applying a suitable current (electroplating basin, for example, connected as an anode and a cathode immersed in the rotating drum), a contact layer can be galvanically deposited on the areas of the components which have been pretreated according to process step A).
Im folgenden soll das erfindungsgemäße Verfahren anhand von Abbildungen und eines Ausführungsbeispiels näher erläutert werden.
Figuren 1A und 1B zeigen die Verfahrensschritte A) und B) des erfindungsgemäßen Verfahrens.The method according to the invention is to be explained in more detail below with the aid of illustrations and an exemplary embodiment. FIGS. 1A and 1B show process steps A) and B) of the process according to the invention.
Figuren 2A und 2B zeigen einen Querschnitt und eine perspek- tivische Ansicht durch ein nach dem erfindungsgemäßen Verfahren hergestelltes keramisches Bauteil mit durchgehender Passivierungsschicht auf den Mantelflächen, wobei anschließend noch nach herkömmlichen Verfahren weitere galvanische Schichten aufgetragen wurden .FIGS. 2A and 2B show a cross section and a perspective view through a ceramic component produced by the method according to the invention with a continuous passivation layer on the lateral surfaces, with further galvanic layers then being applied using conventional methods.
Figuren 3A und 3B zeigen einen Querschnitt und eine perspektivische Ansicht eines nach dem erfindungsgemäßen Verfahren hergestellten keramischen Bauteils mit ebenfalls weiteren nach herkömmlichen Verfahren aufgebrachten Metallisierungsschichten, wobei die Passivierungsschicht die an die Stirnseitenn angrenzenden Bereiche der Mantelflächen freiläßt.FIGS. 3A and 3B show a cross section and a perspective view of a ceramic component produced by the method according to the invention with also further metallization layers applied by conventional methods, the passivation layer leaving free the areas of the lateral surfaces adjoining the end faces.
Die nicht zu galvanisierenden Bereiche des keramischen Bauelements 1 werden vor dem erfindungsgemäßen Verfahren im Verfahrensschritt AI) beispielsweise mit einer Passivierungsschicht aus ZnMn2Ü4 versehen.The areas of the ceramic component 1 which are not to be galvanized are provided with a passivation layer made of ZnMn2Ü4, for example, in method step AI) before the method according to the invention.
Anschließend werden wie in Figur 1A gezeigt, die keramischen Bauelemente 1 mit den Passivierungsschichten 2 mit Schleifkörpern 5 in einer sauren, wässrigen Lösung in Kontakt gebracht (Verfahrenschritt A) . Das Gemenge aus Schleifkörpern und keramischen Bauelementen befindet sich in einer rotieren- den Trommel 10, die in ein Säurebad 15 eintaucht. Die rotierende Bewegung der Trommel ist durch einen Pfeil in Figur 1A dargestellt. Die Trommeldrehachse ist dabei geneigt, um eine abrollende Bewegung des Gemenges aus keramischen Bauelementen und Schleifkörpern zu gewährleisten. Durch das gleichzeitige mechanische Aufrauhen durch die Schleifkörper 5 und die chemische Ätzung im sauren Bad 15 werden die zu galvanisierenden Bereiche 3 der Bauelemente 1 so modifiziert, daß eine zuver-
lässige Haftung der in B) galvanisch aufgebrachten Kontakt- schichten, möglich wird. Als Säurebad wird eine phosphorsaure, wässrige Lösung mit einem pH-Wert von etwa 1,0 bis 1,5 eingesetzt. Die Kontaktflächen und die Kontaktierungswahr- scheinlichkeit zwischen den Schleifkörpern und den keramischen Bauelementen wird dadurch erhöht, daß ein vorteilhaftes Verhältnis von Bauelementlänge zum Schleifkörperdurchmesser eingehalten wird. Dieses beträgt vorteilhafterweise etwa 1 : 0,05 bis 1 : 0,8. Die gesamte Anordnung mit der rotierenden Trommel 10 und dem Schleifkörper-Bauelementgemenge befindet sich in einem Becken 20 zusammen mit dem Säurebad.1A, the ceramic components 1 with the passivation layers 2 are brought into contact with grinding bodies 5 in an acidic, aqueous solution (process step A). The mixture of grinding wheels and ceramic components is located in a rotating drum 10 which is immersed in an acid bath 15. The rotating movement of the drum is shown by an arrow in Figure 1A. The axis of rotation of the drum is inclined in order to ensure a rolling movement of the mixture of ceramic components and grinding wheels. Due to the simultaneous mechanical roughening by the grinding bodies 5 and the chemical etching in the acid bath 15, the areas 3 of the components 1 to be galvanized are modified in such a way that a reliable casual adhesion of the galvanically applied contact layers becomes possible. A phosphoric acid, aqueous solution with a pH of about 1.0 to 1.5 is used as the acid bath. The contact areas and the contacting probability between the grinding wheels and the ceramic components are increased by maintaining an advantageous ratio of component length to grinding wheel diameter. This is advantageously about 1: 0.05 to 1: 0.8. The entire arrangement with the rotating drum 10 and the grinding device component mixture is located in a basin 20 together with the acid bath.
Im Verfahrensschritt B) werden die nach A) vorbehandelten keramischen Bauelemente im Schüttgut galvanisiert (siehe auch Fig. IB) . Dazu bringt man ein Gemenge aus Bauelementen 1 mit einer Passivierungsschicht 2 und Kontaktkörpern 25 in eine rotierende Trommel 10. Diese Trommel taucht in eine Elektrolytlδsung 30, die sich in einem Galvanikbecken 35 befindet. Die Elektrolytlösung besteht beispielsweise aus einer Zinn- Salzlösung mit einer ungefähren Konzentration von 10 bis 20 g SnII/Liter, wobei der pH-Wert ungefähr 3 bis 4,5 beträgt. Als Kontaktkörper werden vorzugsweise elektrisch leitende Kugeln, beispielsweise Stahlkugeln eingesetzt. Um eine galvanische Abscheidung von metallischen Kontaktschichten auf die zu gal- vanisierenden Bereiche 3 der Bauelemente 1 zu ermöglichen, wird das Galvanikbecken 35 als Anode geschaltet und gleichzeitig eine Elektrode 36 in die rotierende Trommel 10 eingetaucht, die als Kathode geschaltet ist. Die abrollende Bewegung der Trommel 10 ermöglicht einen guten Kontakt zwischen den Bauelementen und den Kontaktkörpern, wobei beim erfindungsgemäßen Verfahren vorzugsweise ein Verhältnis von Bauteillänge zu Kontaktkörperdurchmesser im Bereich von etwa 1 : 0,05 bis 1 : 0,08 beträgt. Dadurch erhöht sich die Kontaktwahrscheinlichkeit zwischen den Kontaktkörpern und den Bau- elementen, so daß aufgrund des guten Stromflusses eine gute Abscheidung des Metalls auf den Bereichen 3 möglich ist. Die
Stromdichten liegen dabei vorzugsweise im Bereich von 0,05 bis 0,15 A/dm2.In process step B), the ceramic components pretreated according to A) are galvanized in the bulk material (see also FIG. IB). For this purpose, a mixture of components 1 with a passivation layer 2 and contact bodies 25 is brought into a rotating drum 10. This drum is immersed in an electrolyte solution 30, which is located in an electroplating basin 35. The electrolytic solution consists, for example, of a tin-salt solution with an approximate concentration of 10 to 20 g SnII / liter, the pH being approximately 3 to 4.5. Electrically conductive balls, for example steel balls, are preferably used as contact bodies. In order to enable galvanic deposition of metallic contact layers on the areas 3 of the components 1 to be electroplated, the electroplating basin 35 is switched as an anode and at the same time an electrode 36 is immersed in the rotating drum 10, which is connected as a cathode. The rolling movement of the drum 10 enables good contact between the components and the contact bodies, the ratio of component length to contact body diameter preferably being in the range from about 1: 0.05 to 1: 0.08 in the method according to the invention. This increases the contact probability between the contact bodies and the components, so that a good deposition of the metal on the regions 3 is possible due to the good current flow. The Current densities are preferably in the range from 0.05 to 0.15 A / dm 2 .
Vorzugsweise werden die in B) verwendeten Kontaktkörper auch gleichzeitig als Schleifkörper im Verfahrensschritt A) eingesetzt. Dies ermöglicht einen einfachen und kontinuierlichen Verfahrensprozeß, bei dem nach dem Verfahrensschritt A) die rotierende Trommel aus dem sauren Bad 15 entfernt wird, einige Male mit Wasser gewaschen wird, um keine Kontaminationen des sauren Bades auf den Bauelementen oder Kontakt- beziehungsweise Schleifkörpern in den Verfahrensschritt B) zu überführen. Nach dem Waschen kann das Bauelement- Kontaktkörpergemenge direkt in das Galvanisierungsbad mit der Elektrolytlösung 35 eingetaucht werden und der Verfahrens- schritt B) durchgeführt werden. Dadurch können zusätzliche aufwendige Arbeitsschritte, wie zum Beispiel das Entfernen der Schleifkörper beim Übergang von den Verfahrenschritten A) nach B) vermieden werden.The contact bodies used in B) are preferably also used simultaneously as grinding bodies in process step A). This enables a simple and continuous process, in which after the process step A) the rotating drum is removed from the acid bath 15, washed several times with water, in order to avoid contamination of the acid bath on the components or contact or grinding wheels in the process step B) to convict. After washing, the component / contact body mixture can be immersed directly in the electroplating bath with the electrolyte solution 35 and process step B) can be carried out. As a result, additional complex work steps, such as, for example, removing the grinding wheels during the transition from process steps A) to B) can be avoided.
Die Vorteile der hier vorliegenden Variante des erfindungsgemäßen Verfahrens bestehen auch darin, daß sowohl die Vorbehandlung der zu galvanisierenden Bereiche 3 im Verfahrensschritt A) als auch der Verfahrensschritt B) mit den gleichen für die Galvanisierung vorgesehenen technischen Einrichtungen vorgenommen werden können. Es sind keine umständlichen Einbrennvorgänge von Metalleitpasten oder ein zusätzliches Einbringen der Bauelemente in Glimmentladungszonen mehr nötig.The advantages of the present variant of the method according to the invention also consist in the fact that both the pretreatment of the areas 3 to be galvanized in method step A) and method step B) can be carried out with the same technical devices provided for the galvanizing. There is no longer any need for cumbersome baking processes for metal conductive pastes or additional insertion of the components in glow discharge zones.
In den Figuren 2A uns 2B ist ein nach dem erfindungsgemäßen Verfahren hergestelltes Bauelement 1 (Varistor) mit Innenelektroden 55, die die Kontaktschichten 40 kontaktieren, im Querschnitt und in perspektivischer Ansicht zu sehen. Auf dem Bauelement befindet sich die Passivierungsschicht 2, die die Mantelflächen des Bauelements komplett bedeckt und die im Verfahrensschritt AI) aufgebracht wurde. Nach der Erzeugung der Kontaktschicht 40 mittels des erfindungsgemäßen Verfahrens lassen sich mit dem Stand der Technik entsprechenden
galvanischen Prozessen weitere Kontaktschichten 45 und 50 auf das Bauelement aufbringen. Die Kontaktschicht 50 besteht in der Regel aus Zinn und bestimmt die Löteigenschaften des keramischen Bauelements. In diesem Fall bedecken die Kontakt - schichten nur die Stirnseiten des Bauelements.FIGS. 2A and 2B show a component 1 (varistor) produced by the method according to the invention with internal electrodes 55, which contact the contact layers 40, in cross section and in perspective view. The passivation layer 2, which completely covers the lateral surfaces of the component and which was applied in method step AI), is located on the component. After the contact layer 40 has been produced by means of the method according to the invention, it is possible to use the prior art Apply further contact layers 45 and 50 to the component by means of galvanic processes. The contact layer 50 generally consists of tin and determines the soldering properties of the ceramic component. In this case, the contact layers only cover the end faces of the component.
In den Figuren 3A und 3B ist ein nach dem erfindungsgemäßen Verfahren hergestelltes Bauelement, ein Varistor, ebenfalls im Querschnitt und in perspektivischer Ansicht zu sehen. Es ist zu erkennen, daß in diesem Falle nach dem Verfahrensschritt AI) eine Passivierungsschicht 2 vorhanden ist, die nur Teile der Mantelflächen des Bauelements bedeckt, während die Stirnseiten und an die Stirnseiten angrenzende Bereiche der Mantelflächen freigelassen werden. In dem Bauelement be- finden sich Innenelektroden 55, die die nach dem erfindungsgemäßen Verfahren in B) aufgebrachten Kontaktschichten 40 kontaktieren. Mit herkömmlichen galvanischen Verfahren lassen sich weitere Kontaktschichten 45 und 50 aufbringen. In diesem Fall bedecken die Kontaktschichten die Stirnseiten und die daran angrenzenden Bereiche der Mantelflächen des Bauelements .FIGS. 3A and 3B show a component, a varistor, produced by the method according to the invention, also in cross section and in a perspective view. It can be seen that in this case, after the process step AI), a passivation layer 2 is present, which only covers parts of the lateral surfaces of the component, while the end faces and regions of the lateral surfaces adjacent to the end faces are left free. Inside the component there are internal electrodes 55 which contact the contact layers 40 applied by the method according to the invention in B). Further contact layers 45 and 50 can be applied using conventional galvanic processes. In this case, the contact layers cover the end faces and the regions of the lateral surfaces of the component which are adjacent thereto.
Das erfindungsgemäße Verfahren beschränkt sich nicht auf das hier vorgestellte Ausführungsbeispiel. Weitere Variationen sind sowohl hinsichtlich der chemischen und mechanischen Vorbehandlung der Bauelemente als auch bezüglich der verwendeten Elektrolytlösungen und Schleifkörper, sowie Kontaktkörper möglich. Mit dem erfindungsgemäßen Verfahren lassen sich Kontaktschichten direkt auf eine ganze Reihe von keramischen Bauelementen, beispielsweise Varistoren oder Thermistoren, oder andere keramische Bauelemente aufbringen.
The method according to the invention is not limited to the exemplary embodiment presented here. Further variations are possible with regard to the chemical and mechanical pretreatment of the components as well as with regard to the electrolyte solutions and grinding media used, as well as contact bodies. With the method according to the invention, contact layers can be applied directly to a whole series of ceramic components, for example varistors or thermistors, or other ceramic components.
Claims
Patentansprücheclaims
1. Verfahren zum direkten Galvanischen Aufbringen von Kontaktschichten auf keramische Bauelemente mit den Verfah- rensschritten,1. Method for the direct galvanic application of contact layers on ceramic components with the method steps,
A) die zu galvanisierenden Bereiche (3) des keramischen Bauelements (1) werden zuerst durch mechanische und chemische Behandlung in einer phosphorsauren, wässrigen Lösung mit einem pH-Wert von etwa 1,0 bis 1,5 aktiviert, B) die Kontaktschichten (40) werden danach durch einen galvanischen Prozeß direkt auf das mit der Lösung behandelte keramische Bauelement (1) aufgebracht.A) the areas (3) of the ceramic component (1) to be electroplated are first activated by mechanical and chemical treatment in a phosphoric acid, aqueous solution with a pH of about 1.0 to 1.5, B) the contact layers (40 ) are then applied directly to the ceramic component (1) treated with the solution by means of a galvanic process.
2. Verfahren nach Anspruch 1, - bei dem vor den Verfahrensschritten A) und B) in einem2. The method according to claim 1, - in which before the process steps A) and B) in one
Verfahrenschritt AI) zuerst eine Passivierungsschicht (2) auf die nicht zu galvanisierenden Bereiche des keramischen Bauelements (1) aufgebracht wird.Process step AI) first a passivation layer (2) is applied to the areas of the ceramic component (1) that are not to be galvanized.
3. Verfahren nach dem vorhergehenden Anspruch, bei dem im Verfahrensschritt AI) eine hochohmige Passivierungsschicht verwendet wird.3. The method according to the preceding claim, in which a high-resistance passivation layer is used in process step AI).
4. Verfahren nach einem der Ansprüche 2 bis 3, - bei dem im Verfahrensschritt AI) Spinelle der allgemeinen Formel AB2O4, oder Perowskite der folgenden allgemeinen Formel4. The method according to any one of claims 2 to 3, - in which in process step AI) spinels of the general formula AB2O4, or perovskites of the following general formula
M II x M11IH. l-x _τ11-i IV x+y rroxll- yr1-n0xlll l-x-2yu3M II x M 11 IH. lx _τ 11 -i IV x + y rr o xll- yr 1 -n 0 xlll lx-2y u 3
bei der das zweiwertige Metall M^- entweder Strontium oder Barium und das dreiwertige Metall M^11 ein Element der Seltenen Erden ist, bei der gilt: 0 < x < 0,85; 0 < y < (l-x)/2 und x+y < 1
oder eine Blei-Lanthan-Zirkon-Titanat-Keramik der allgemeinen Formel (Pb,La) (Zr,Ti)θ3 als Passivierungsschichten verwendet werden.in which the divalent metal M ^ - either strontium or barium and the trivalent metal M ^ 11 is a rare earth element, where: 0 <x <0.85; 0 <y <(lx) / 2 and x + y <1 or a lead-lanthanum-zirconium-titanate ceramic of the general formula (Pb, La) (Zr, Ti) θ3 can be used as passivation layers.
Verfahren nach einem der vorhergehenden Ansprüche, bei dem im Verfahrensschritt A) die mechanische Behandlung durch Aufrauhen und die chemische Behandlung durch Ätzen der zu galvanisierenden Bereiche (3) des keramischen Bauelements erfolgt.Method according to one of the preceding claims, in which in method step A) the mechanical treatment is carried out by roughening and the chemical treatment is carried out by etching the regions (3) of the ceramic component to be galvanized.
Verfahren nach dem vorhergehenden Anspruch, bei dem im Verfahrensschritt A) Schleifkörper (5) verwendet werden, die in sauren wässrigen Lösungen (15) auf die keramischen Bauelemente einwirken.Method according to the preceding claim, in which grinding step (5) is used in process step A), which act on the ceramic components in acidic aqueous solutions (15).
Verfahren nach Anspruch 6 , bei dem als Schleifkörper (5) Stahlkugeln verwendet werden.Method according to Claim 6, in which steel balls are used as the grinding body (5).
8. Verfahren nach einem einem der Ansprüche 6 bis 7, bei dem keramische Bauelemente und Schleifkörper verwendet werden, die ein Verhältnis von Bauelementlänge zu Schleifkörperdurchmesser von etwa 1:0,05 bis 1:0,8 aufweisen.8. The method according to any one of claims 6 to 7, are used in the ceramic components and grinding wheels, which have a ratio of component length to grinding wheel diameter of about 1: 0.05 to 1: 0.8.
9. Verfahren nach einem der vorhergehenden Ansprüche,9. The method according to any one of the preceding claims,
- bei dem im Verfahrensschritt B) die keramischen Bauelemente mit elektrisch leitenden Kontaktkörpern (25) in einer ein Metallsalz umfassenden Elektrolytlösung (30) in Kontakt gebracht werden und ein elektrischer Stromfluß mit einer geeigneten Stromdichte so angelegt wird, daß eine galvanische Abscheidung des Metalls auf den zu galvanisierenden Bereichen (3) der keramischen Bauelemente erfolgt.- In the process step B) the ceramic components with electrically conductive contact bodies (25) are brought into contact in an electrolyte solution (30) comprising a metal salt and an electrical current flow is applied with a suitable current density in such a way that galvanic deposition of the metal on the to galvanized areas (3) of the ceramic components.
10. Verfahren nach dem vorhergehenden Anspruch, - bei dem die keramischen Bauelemente derart mit den Kontaktkörpern in Kontakt gebracht werden, daß die Bauelemen-
te und die Kontaktkörper eine Relativbewegung zueinander ausführen.10. The method according to the preceding claim, - in which the ceramic components are brought into contact with the contact bodies in such a way that the components te and the contact body perform a relative movement to each other.
11. Verfahren nach einem der Ansprüche 9 oder 10, - bei dem als Elektrolytlösung (30) eine Zinn (II) -Lösung mit einer ungefähren Konzentration von 10 bis 20 g/Sn(II) je Liter bei einem ungefähren pH-Wert von 3 bis 4,5 verwendet wird.11. The method according to any one of claims 9 or 10, - in which as the electrolyte solution (30) a tin (II) solution with an approximate concentration of 10 to 20 g / Sn (II) per liter at an approximate pH value of 3 up to 4.5 is used.
12. Verfahren nach einem der Ansprüche 9 bis 11, bei dem Stromdichten im ungefähren Bereich von 0,05 bis 0,15 A/dm2 eingesetzt werden.12. The method according to any one of claims 9 to 11, are used in the current densities in the approximate range of 0.05 to 0.15 A / dm 2 .
13. Verfahren nach einem der Ansprüche 9 bis 12, - bei dem keramische Bauelemente (1) und Kontaktkörper (25) verwendet werden, die ein Verhältnis von Bauelementlänge zu Kontaktkörperdurchmesser von etwa 1:0,05 bis 1:0,8 aufweisen.13. The method according to any one of claims 9 to 12, - are used in the ceramic components (1) and contact body (25), which have a ratio of component length to contact body diameter of about 1: 0.05 to 1: 0.8.
14. Verfahren nach einem der Ansprüche 6 bis 13, bei dem die im Verfahrenschritt B) eingesetzen Kontaktkörper (25) auch im Verfahrenschritt A) als Schleifkörper (5) verwendet werden .
14. The method according to any one of claims 6 to 13, in which the contact body (25) used in method step B) are also used in method step A) as grinding wheel (5).
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE10147897A DE10147897C1 (en) | 2001-09-28 | 2001-09-28 | Process for directly galvanizing contact layers onto ceramic components comprises activating the regions to be galvanized using an aqueous solution containing phosphoric acid, and applying the contact layers on the treated components |
DE10147897 | 2001-09-28 | ||
PCT/DE2002/002931 WO2003031671A2 (en) | 2001-09-28 | 2002-08-08 | Method for electroplating of contact layers on ceramic components |
Publications (1)
Publication Number | Publication Date |
---|---|
EP1530654A2 true EP1530654A2 (en) | 2005-05-18 |
Family
ID=7700645
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP02754511A Withdrawn EP1530654A2 (en) | 2001-09-28 | 2002-08-08 | Method for electroplating of contact layers on ceramic components |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP1530654A2 (en) |
DE (1) | DE10147897C1 (en) |
TW (1) | TW572869B (en) |
WO (1) | WO2003031671A2 (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE10147898A1 (en) * | 2001-09-28 | 2003-04-30 | Epcos Ag | Electrochemical component with multiple contact surfaces |
US8025808B2 (en) | 2003-04-25 | 2011-09-27 | Saint-Gobain Ceramics & Plastics, Inc. | Methods for machine ceramics |
US7306748B2 (en) * | 2003-04-25 | 2007-12-11 | Saint-Gobain Ceramics & Plastics, Inc. | Methods for machining ceramics |
EP2121244B1 (en) | 2006-12-20 | 2013-07-10 | Saint-Gobain Ceramics & Plastics, Inc. | Methods for machining inorganic, non-metallic workpieces |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3035944A (en) * | 1960-08-05 | 1962-05-22 | Ben C Sher | Electrical component preparation utilizing a pre-acid treatment followed by chemical metal deposition |
DE3512342C2 (en) * | 1985-04-04 | 1993-12-23 | Daimler Benz Ag | Process for metallizing an electrically insulating surface |
JPH0653253B2 (en) * | 1986-11-08 | 1994-07-20 | 松下電工株式会社 | Roughening method of ceramic substrate |
DE4138214A1 (en) * | 1991-11-21 | 1993-05-27 | Daimler Benz Ag | Metallisation of aluminium nitride ceramic - involves ceramic treatment to remove glass surface film |
DE4238242C2 (en) * | 1992-09-17 | 2003-04-24 | Rieger Franz Metallveredelung | Process for pretreating light metals according to patent DE 4231052 C2 |
JPH0776763A (en) * | 1993-09-01 | 1995-03-20 | Praxair St Technol Inc | Member for galvanization bath excellent in resistance to blocking to alloy layer, its preparation and hot dip galvanization therewith |
-
2001
- 2001-09-28 DE DE10147897A patent/DE10147897C1/en not_active Expired - Lifetime
-
2002
- 2002-08-08 EP EP02754511A patent/EP1530654A2/en not_active Withdrawn
- 2002-08-08 WO PCT/DE2002/002931 patent/WO2003031671A2/en not_active Application Discontinuation
- 2002-08-16 TW TW91118564A patent/TW572869B/en active
Non-Patent Citations (1)
Title |
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See references of WO03031671A2 * |
Also Published As
Publication number | Publication date |
---|---|
WO2003031671A2 (en) | 2003-04-17 |
TW572869B (en) | 2004-01-21 |
DE10147897C1 (en) | 2003-01-23 |
WO2003031671A3 (en) | 2005-03-24 |
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