| 摘要 |
<p>A semiconductor ceramic of the present invention includes a Ba m TiO 3 -based composition, as a main component, having a perovskite structure represented by general formula A m BO 3 . Part of Ba constituting an A site is replaced with at least an alkali metal element, Bi, and a rare-earth element, and the molar ratio m between the A site and a B site is 0. 990 ‰¤ m ‰¤ 0.999 (preferably 0.990 ‰¤ m ‰¤ 0.995). Preferably part of the Ba is replaced with Ca, and the content of the Ca when the total number of moles of the elements constituting the A site is 1 mole is 0.042 to 0.20 (preferably 0.125 to 0.175) on a molar ratio basis. A PTC thermistor includes a component body 1 formed of the semiconductor ceramic. Accordingly, there are provided satisfactory rise characteristics even if an alkali metal element is contained.</p> |
