| 摘要 |
PURPOSE: To stably ensure the vertical tensile strength that is larger than the specific value per unit area and also to secure the no-load Q (Qu) that is sufficiently large for practical use by etching the ceramic surface to be plated while applying an ultrasonic treatment on this surface so as to keep the maximum roughness within a specific range for the ceramic surface. CONSTITUTION: A CU film base layer is formed on a high frequency dielectric ceramics by the electroless plating, and a CU film, an Ag film or both CU and Ag films are formed on the CU film base layer as an electrode by the electrolytic plating. In such a constitution of a coaxial dielectric resonator, the ceramic surface to be plated is etched while undergoing an ultrasonic treatment. Thus the maximum roughness of the ceramic surface is defined as Rmax = 1.0 to 3.0μm. The dielectric ceramics uses one of Ba0-TiO2 -RO, BaO-TiO2 -Bi2 O3 -RO and BaO-TiO2 -Bi2 O3 -PbO-RO groups, where RO shows a rare-earth element and R shows one of La, Ce, Pr, Nd, etc. Thus the vertical tensile strength can be stably kept at 2.0kg/mm<2> or more. |
