3 - Dielectric composition for low temperature sintered SrTiO3 varistor-capacitor multifunctional device

摘要

PURPOSE: A low temperature sintered SrTiO3 varistor-capacitor dual function device dielectric compound is provided to reduce a sintering temperature from 1400C to 1200C. CONSTITUTION: A low temperature sintered SrTiO3 varistor-capacitor dual function device dielectric compound is Sr(1-x-y)BaxCayTiO3. The basic material powder is subjected to wet milling for 24 hours after Nb2O5 is added for increasing conductivity of grain. The basic material powder is dried and PVA(poly-vinyl alcohol) of 2 mol% is added, after wet ball milling. Molding is carried out at 100MPa. The molded sample is sintered in a reduction furnace with N2 and H2 gas of 90 to 10 mixture ratio. The sintered sample is re-oxidized at 900C to oxidize grain boundary and sample surface so as to form a high resist layer. On the re-oxidized sample, outer electrodes are formed by thermally processing Ag electrodes.