Dielectric ceramic for microwaves
AssigneeKYOCERA Corporation
InventorsSeiichiro Hirahara, Nobuyoshi Fujikawa
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Abstract
In a dielectric ceramic composed of a La.sub.2 O.sub.3 -CaO-TiO.sub.2 -MgO type or a BaO-Nd.sub.2 O.sub.3 -TiO.sub.2 type, the oxygen vacancy concentration of the ceramic is controlled below 7.times.10.sup.18 /cm.sup.3 by, for example, annealing the mixture after firing, or heat-treating the mixture after firing. The Q value of the dielectric ceramic can be markedly increased. In addition, ceramics having stable properties can be produced. Thus, the dielectric ceramics can fully cope with high frequencies and large electrification.
Claims8
A dielectric ceramic composition for microwaves comprising metal complex oxides having an oxygen vacancy concentration of not more than 7.times.10.sup.18 /cm.sup.3 wherein the metal complex oxides comprise Ti or Ti ions as a metal component.
A dielectric ceramic composition for microwaves comprising metal complex oxides having an oxygen vacancy concentration of not more than 7.times.10.sup.18 /cm.sup.3 wherein the metal complex oxides comprises La, Ti, Mg and Ca, and wherein the atomic ratio of La:Ti:Mg:Ca is in the range of 15-60:15-45:7.5-45:0-35.
Dependencies are inferred from the claim text.