| abstract |
The semiconductor ceramic of the present invention contains a BaTiO 3 -based composition having a perovskite structure represented by the general formula A m BO 3 as a main component, and a part of Ba constituting the A site is an alkali metal element, Bi, Ca, The content of Ca and Sr when substituted with Sr and a rare earth element and the total mole number of the elements constituting the A site is 1 mol is obtained when the molar ratio of Ca is x and the molar ratio of Sr is y. , 0.05 ≦ x ≦ 0.20, 0.02 ≦ y ≦ 0.12, and 2x + 5y ≦ 0.7. In the PTC thermistor, the component body 1 is formed of this semiconductor ceramic. As a result, even when the alkali metal element or Bi is contained, surface discoloration does not occur, and a lead-free semiconductor ceramic with good reliability capable of suppressing deterioration of resistance value even after energizing for a long time is obtained. |