| 摘要 |
PURPOSE: To increase a capacity and improve an antisurge property by including a ceramic layer of a perovskite structure, chief component of which is (Ba, Ca, Sr) (Ti, Zr)O3 . CONSTITUTION: A ceramic layer 2 is mainly constituted of a composite oxide including Ti and/or Zr and Ba and forms a perovskite-type oxide which has a high relative permittivity. It includes Si and/or Al as an assistant component. This composite oxide is expressed by a formula (Ba1-x-y Cax Sry )m (Ti1-z Zrz )O3 (O<=x<=0.4), O<=y<=0.4, O<=z<=0.3, 0.9<=m<=1.2). By not including Cr substantially in the ceramic layer 2, an antisurge property can be improved. An inner electrode layer 3 is made of conductive material, chief of which is base metal. By this method, a capacity of a stack-type varistor can be increased and an antisurge property is also improved. |
