MANUFACTURE OF ZNO VARISTOR DEVICE

摘要

PROBLEM TO BE SOLVED: To permit simultaneous integral burning of a varistor element and electrodes, by forming a material comprising ZnO as a primary component including at least Bi, Sb, Al and Ta with the addition of a specific percentage of Cr, further forming electrodes on both main planes of the resultant, and burning at a specific temperature. ;SOLUTION: A varistor element 1 is obtained by forming a material which comprises ZnO as a primary component including at least Bi, Sb, Al and Ta as subcomponents, with the addition of 0.01-1.0 mol.% of Cr with respect to ZnO so that the ratio of Ta/Cr becomes 0.5-2.0 in terms of Cr₂O₃. Subsequently, after forming electrodes 2 on both of the main planes of the varistor element 1, the element 1 is integrally burnt with the electrodes 2 at the temperature of 800-960°C. Further, after mixing Ta, Cr and Sb at a fixed ratio, followed by tentative burning and grinding thereof, the resultant is added to the material comprising ZnO as a primary component, thereby obtaining a varistor device.;COPYRIGHT: (C)1999,JPO