| 摘要 |
PURPOSE: To elevate a withstand voltage strength and a ratio of withstand voltage/resistivity by a method wherein a fine material powder uniformly including yttrium being semiconducting agent by wet reaction is used, and also a Y/Ti atomic ratio and a Ba/Ti atomic ratio are strictly controlled. CONSTITUTION: In a barium titanate based semiconductor ceramics having a perovskite crystal structure including yttrium as semiconducting agent, a Y/Ti atomic ratio and a Ba/Ti atomic ratio are within a scope enclosed with ABCD are also a mean grain diameter of semiconductor ceramics is 1 to 2μm, and also a maximum grain diameter is 5μm or less. As a characteristic of semiconductor ceramics, in barium titanate based semiconducting ceramics, a withstand voltage strength is 500V/mm or more, and also resistivity in the withstand voltage strength/room temperature is 5 or more. Thus, it is possible to obtain semiconductor ceramics excellent in practicality at low cost. |
