A low-temperature, high stability co-fired microwave dielectric composite of ceramic and glass, including 85-99 wt % microwave dielectric ceramic of formula [1-y-z[(1−x)Mg.sub.2SiO.sub.4−xCa.sub.2SiO.sub.4]−yCaTiO.sub.3−zCaZrO.sub.3, wherein 0.2≦x≦0.7,0.05≦y≦0.3 and 0.02≦z≦0.15], and 1 to 15 wt % with Li.sub.2O—BaO—SrO—CaO—B.sub.2O.sub.3—SiO.sub.2 glass respectively made at a low sintering temperature of ceramic for co-firing with Ag or Cu electrode, employing eutectic phase of ceramic oxides to reduce its melting temperature, a low melting-point glass material with high chemical stability as a sintering aid added to oxides and raw material powders of Li.sub.2O, BaO, SrO, CaO, B.sub.2O.sub.3 and SiO.sub.2, obtained by combining and melting the ingredients in the temperature range between 1000 to 1300° C., quenching and crashing, and then adding it to the main ceramic oxides to form the final composition. This ceramic/glass composite material may be co-fired with an Ag and Cu electrode at 900° C.-970° C. for 0.5-4 hours in a protective atmosphere. After sintering, this dielectric material possesses efficacious microwave dielectric properties, dielectric constant between middle-K to low-K at 8.sup.−15, high quality factors, low dielectric loss, low temperature-capacitance coefficient and superior chemical stability suitable for manufacture of multilayer ceramic devices.

A piezoelectric material contains: a first component which is a rhombohedral crystal in a single composition, has a Curie temperature Tc1, and is a lead-free-system composite oxide having a perovskite-type structure; a second component which is a crystal other than the rhombohedral crystal in a single composition, has a Curie temperature Tc2<Tc1, and is a lead-free-system composite oxide having a perovskite-type structure; and a third component which is a crystal other than the rhombohedral crystal in a single composition similar to the second component, has a Curie temperature Tc3≧Tc1, and is a lead-free-system composite oxide that has a perovskite-type structure and is different from the second component. When a molar ratio of the third component to the sum of the second component and the third component is α and α×Tc3+(1−α)×Tc2 is Tc4, |Tc4−Tc2|≦50° C.

The present invention provides a method for making a high strength, small grain size ceramic having a trans-granular fracture mode by rapid densification of a green body and subsequent cooling of the densified ceramic. The ceramic may include dislocations, defects, dopants, and/or secondary phases that are formed as a result of the process and resulting in stress fields capable of redirecting or arresting cracks within the material. This ceramic can maintain transparency from ultraviolet to mid-wave infrared.

A multilayer ceramic capacitor that includes a laminated body of multiple dielectric layers and internal electrodes laminated alternately therewith. The dielectric layers contain Ba, Sr, Ti, Ca, Zr, Mg, and R, where R represents at least one element of Y, La, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb. When Ti is 100 parts by mol, the dielectric layers contain Sr at 0.5 to 3.0 parts by mol; Ca at 3 to 15 parts by mol; Sr at 0.05 to 3.0 parts by mol; Mg at 0.01 to 0.0 9 parts by mol; and R at 2.5 to 8.4 parts by mol.

A thermistor material and a method for preparing a thermistor material are provided. The thermistor material is prepared by mixing and heating a mixture containing BaTiO.sub.3, B.sub.2O.sub.3, SiO.sub.2, Li.sub.2O, P.sub.2O.sub.5, Cs.sub.2O, Nd.sub.2O.sub.3, Al.sub.2O.sub.3 and TiO.sub.2.

Provided is a dielectric thin film including a metal oxide. The metal oxide includes bismuth, sodium, barium, and titanium, at least a part of the metal oxide is a tetragonal crystal having a perovskite structure, and a (100) plane of at least a part of the tetragonal crystal is oriented in a normal direction do of a surface of the dielectric thin film 3.

A ceramic green sheet where the proportion of a Si-containing constituent coating the surface of barium titanate-based ceramic particles is 95% or higher, and the proportion of a rare-earth element-containing constituent coating the surface of the barium titanate-based ceramic particle is 85% or higher.

A method for producing a multilayer ceramic capacitor that includes preparing a dielectric ceramic material by mixing a perovskite compound, a Re compound, a Mn compound, a Mg compound, and a Si compound. The perovskite compound contains Ba and Ti and has 1.2×10.sup.15 or more and 4.5×10.sup.15 or less Ba vacancies per gram. Re in the Re compound is at least one element selected from Y, Gd, Tb, Dy, Ho, Er, and Yb. Green sheets containing the dielectric ceramic material are then formed. Inner electrode patterns are then formed on some of the green sheets. An unsintered capacitor body is then formed by stacking the green sheets, some of which have the inner electrode patterns formed thereon. Sintering of the unsintered capacitor body is then conducted.

A dielectric ceramic composition and a multilayer ceramic capacitor comprising the same are provided. The dielectric ceramic composition includes a BaTiO.sub.3-based base material main ingredient and an accessory ingredient, where the accessory ingredient includes dysprosium (Dy) and cerium (Ce) as first accessory ingredients. A total content of Dy and Ce is greater than 0.25 mol % and equal to or less than 1.0 mol % based on 100 mol % of the base material main ingredient.

Disclosed herein are embodiments of materials having high thermal conductivity along with a high dielectric constants. In some embodiments, a two phase composite ceramic material can be formed having a contiguous aluminum oxide phase with a secondary phase embedded within the continuous phase. Example secondary phases include calcium titanate, strontium titanate, or titanium dioxide.