| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a semiconductor ceramic allowing to suppress variation of resistance values among products while keeping appropriate high Curie point even with small amount of alkali metal elements and Bi contained therein. <P>SOLUTION: This semiconductor ceramic comprises Ba<SB>m</SB>TiO<SB>3</SB>-based composition having a perovskite type structure expressed by general formula A<SB>m</SB>BO<SB>3</SB>as a main component, where a part of Ba constituting the A site is substituted by alkali metal elements, Bi, Ca and rare earth elements; the total content of the alkali metal elements and the Bi is 0.02-0.09 in terms of molar ratio when the total number of moles of elements constituting the A site is made 1 mole; and the content of the Ca is 0.05-0.20 (preferably 0.125-0.175) in terms of molar ratio when the total number of moles of elements constituting the A site is made 1 mole. In the PTC thermistor, the body 1 of parts is formed of the above semiconductor ceramic. <P>COPYRIGHT: (C)2010,JPO&INPIT |
