GRAIN BOUNDARY INSULATION TYPE SEMICONDUCTOR PORCELAIN COMPOSITION

PURPOSE:To obtain a dielectric porcelain of improved characteristics by insulating a crystalline grain boundary of semiconductor ceramic, adding ZnO, MnO2, and one kind selected from a group of Y2O3, La2O3, Nb2O5, Ta2O5 and WO3 as a valance control agent. CONSTITUTION:For a main constituent 100mol part consisting of SrO 49.5 to 50.5mol% and TiO2 49.5 to 50.5mol%, a crystalline grain boundary of a semiconductor ceramic made by adding 0.01 to 3.0mol part of ZnO, 0.01 to 3.0mol part of MnO2, and 0.02 to 1.0mol part of at least one kind of Y2O3, La2O3, Nb2O5, Ta2O5, and WO3 as a valance control agent is insulated. Thus, a grain boundary insulation type semiconductor porcelain composition which can constitute a capacitor with a large dielectric constant, improved temperature characteristics, a small dielectric loss, and improved frequency characteristics can be obtained.