CERAMIC COMPONENT AND METHOD FOR PRODUCING THE CERAMIC COMPONENT

Abstract

A ceramic component having a ceramic main part containing AxByC1?x?vTi1?y+wO3*(Mn2P2O7)z*Du, in which A is a first dopant selected from a group including neodymium, praseodymium, cerium, and lanthanum, B is a second dopant selected from a group including niobium, tantalum, and vanadium, C is selected from a group including calcium, strontium, and barium, and D includes a metal selected from a group including aluminum, nickel, and iron. x is the proportion of A, y is the proportion of B, v is the proportion of A vacancies, w is the proportion of excess titanium, z is the proportion of Mn2P2O7, u is the proportion of D, and the following applies: 0.0?x<0.1, 0.0?y<0.1, 0?v<1.5*x, 0?w<0.05, 0.01?z<0.1, 0?u<0.05. A method for producing the ceramic component is also disclosed.

Claims

1-14. (canceled)

15. A ceramic material comprising a base compound with the general empirical formula CTiO.sub.3 and manganese pyrophosphate as a sintering aid.

16. The ceramic material according to claim 15, wherein C comprises one or more selected from calcium, strontium, and barium.

17. The ceramic material according to claim 15, which contains a first doping selected from neodymium, praseodymium, cerium, and lanthanum, which occupies some of the C positions in a crystal lattice.

18. The ceramic material according to claim 15, which contains a second doping selected from niobium, tantalum, and vanadium, which occupies some of the positions of titanium in a crystal lattice.

19. The ceramic material according to claim 15, which contains an additive selected from aluminum, nickel and iron.

20. A ceramic component comprising a ceramic base body having as a main component a ceramic material according to claim 15 in a sintered state.

21. A ceramic material having the empirical formula A.sub.xB.sub.yC.sub.1-x-vTi.sub.1-y+wO.sub.3*(Mn.sub.2P.sub.2O.sub.7).sub.z*D.sub.u, wherein A is a first doping which is selected from a group of first metals comprising neodymium, praseodymium, cerium, and lanthanum, B is a second doping which is selected from a group of second metals comprising niobium, tantalum, and vanadium, C is a main constituent of a base ceramic material selected from a group of third metals comprising calcium, strontium, and barium and D is an additive which comprises at least one first compound containing a fourth metal selected from a group of fourth metals comprising aluminium, nickel, and iron, wherein x is the molar proportion of A, y is the molar proportion of B, v is the molar proportion of A vacancies, w is the molar proportion of a titanium excess, z is the molar proportion of manganese pyrophosphate, u is the molar proportion of D and the following holds true for the molar proportions: 0.0?x<0.1, 0.0?y<0.1, 0?v<1.5*x, 0?w<0.05, 0.01?z<0.1, 0?u<0.05.

22. A ceramic component comprising a ceramic base body having as a main component a ceramic material according to claim 20 in a sintered state.

23. A method for producing a ceramic component, wherein the method has at least the following sub-steps: providing a base ceramic material having the general empirical formula CTiO.sub.3, wherein C is a main component of the base ceramic material comprising a third metal selected from a group of third metals comprising calcium, strontium, barium, Preparing a mixture by adding manganese pyrophosphate to the base ceramic material, Production of unsintered components comprising the mixture sintering the unsintered components, wherein manganese pyrophosphate acts as a sintering aid, whereby sintered components are obtained.

24. The method according to claim 23, wherein sintering the unsintered components is performed at 1200 and 1250? C.

25. A method for producing a ceramic component, wherein the method has the following sub-steps: providing a base ceramic material having the empirical formula CTiO.sub.3, wherein C is a main constituent of the base ceramic material comprising a third metal selected from a group of third metals comprising calcium, strontium, barium, adding manganese pyrophosphate, a first dopant which contains a first metal and/or a second dopant which contains a second metal and/or a Ti-containing compound and/or an additive which comprises at least one first compound containing a fourth metal to the ceramic material, with subsequent mixing to obtain a mixture, wherein the first metal is selected from a group of first metals comprising neodymium, praseodymium, cerium, and lanthanum, the second metal is selected from a group of second metals comprising niobium, tantalum, and vanadium, the third metal is selected from a group of third metals comprising calcium, strontium, and barium, and the fourth metal is selected from a group of fourth metals comprising aluminum, nickel, and iron, grinding the mixture to obtain a ground mixture, producing ceramic green sheets from the ground mixture, applying inner electrodes to the ceramic green sheets, stacking the ceramic green sheets to obtain a stack of green sheets, pressing the stack of green sheets to obtain a pressed stack of green sheets, singulating the pressed stack to obtain singulated green structural parts, decarburizing the singulated structural parts to obtain decarburized structural parts, sintering the decarburized structural parts to obtain sintered structural parts, tempering the sintered structural parts to obtain ceramic base bodies, applying metallizations to and firing metallizations on outer surfaces of the ceramic base bodies to obtain ceramic components.

26. A use of manganese pyrophosphate as a sintering aid for sintering ceramic material comprising a base compound with the general molecular formula CTiO.sub.3.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0064] FIGURE shows a ceramic component having a ceramic base body.

[0065] The FIGURE and the size ratios in the FIGURE are not true to scale.

DETAILED DESCRIPTION

[0066] FIGURE shows a ceramic component having a ceramic base body 1 with internal inner electrodes 2 and two metallizations 3, which are attached to two opposite outer surfaces 1 of the ceramic base body 1. In addition, the ceramic base body 1 has a passivation 4 of glass. The ceramic component is in the form of a multilayer capacitor. The ceramic base body contains, as the main constituent, a ceramic material with the empirical formula La.sub.0.2Ba.sub.0.194Sr.sub.0.776Ti.sub.1O.sub.3*(Mn.sub.2P.sub.2O.sub.7).sub.0.01 and thus corresponds to the composition of the first example shown in Table 1.

[0067] A base ceramic material with the empirical formula Ba.sub.0.2Sr.sub.0.8TiO.sub.3 was provided for the production of a ceramic base body for an exemplary embodiment. Lanthanum oxide as the first dopant, titanium dioxide as the titanium-containing compound, and manganese pyrophosphate were added to the base ceramic material. The sum of the molar proportions of the base ceramic material, the first dopant, the titanium-containing compound and the manganese pyrophosphate is 100 mol %. Thus, the molar proportion of the base compound is 97 mol %, the molar proportion of the first dopant is 1 mol %, the molar proportion of the titanium-containing compound is 1.5 mol % and the molar proportion of manganese pyrophosphate is 0.5 mol %. Subsequently, the base ceramic material, the first dopant, the titanium-containing compound and the manganese pyrophosphate were mixed together and ground to obtain a ground mixture.

[0068] From the ground mixture ceramic green sheets were produced, to which inner electrodes were applied by means of a metal-containing paste containing nickel. In a subsequent step, the printed green sheets were stacked to form a stack of green sheets and were pressed to obtain a pressed stack of green sheets. After this, the pressed stack of green sheets was singulated and then the singulated structural parts were decarburized at 600? C. and sintered at 1250? C. for four hours in a reducing atmosphere in order to obtain a ceramic base body 1. In a further step, metallizations 3 were applied to two opposite outer surfaces 1 of the ceramic base body 1. Finally, the ceramic base body 1 was subjected to a passivation 4 of glass.

[0069] The invention is not restricted to the above exemplary embodiment. In particular, the ceramic material can comprise a composition corresponding to Examples 2 to 7 from Table 1. The ceramic material can, however, also comprise a composition which differs from the compositions shown in Examples 1 to 7 in Table 1, Examples 1 to 7 being considered to be preferred. The use of the ceramic material is also not restricted to a capacitor.

LIST OF REFERENCE DESIGNATIONS

[0070] 1 Ceramic base body [0071] 1 Outer surface [0072] 2 Inner electrodes [0073] 3 Outer metallization [0074] 4 Passivation