Abstract: A semiconductor ceramic composition including a compound represented by the following general formula (1) as a main component. (BavBixAyREw)m(TiuTMz)O3 ??(1) (wherein, A represents both elements of Na and K; RE is at least one element selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Gd, Dy and Er; and TM is at least one element selected from the group consisting of V, Nb and Ta.) 0.01?x?0.15 ??(2) x?y?0.3 ??(3) 0?(w+z)?0.01 ??(4) v+x+y+w=1 ??(5) u+z=1 ??(6) 0.950?m?1.050 ??(7) further, 0.001 mol to 0.055 mol of Ca is included and the ratio of Na/(Na+K) is 0.1 or more and less than 1.

Abstract: A semiconductor ceramic composition with small resistivity at room temperature and large temperature coefficient of resistance is provided; the composition is represented by formula, (Ba1-x-y-wBixAyREw)m(Ti1-zTMz)O3??(1), (wherein, A is at least one element from Na or K, RE is at least one element from the group consisting of Y, La, Ce, Pr, Nd, Sm, Gd, Dy and Er, TM is at least one element from the group consisting of V, Nb and Ta, and w, x, y, z (each in mol) and the mole ratio m of Ba site to Ti site satisfy the following in equations, 0.007?x?0.125??(2) x<y?2.0x??(3) 0?(w+z)?0.010??(4) 0.940?m?0.999??(5)), and further includes Sr in a proportion of 0.010 mol or more and 0.050 mol or less relative to 1 mol of Ti site, and the mole ratio u of Sr and the mole ratio x of Bi satisfy the following in equation, u?1.8x?0.008??(6).

Abstract: A semiconductor ceramic composition which includes a compound represented by the following formula (1) as a main component, (Ba1-x-y-wBixAyREw)m(Ti1-zTMz)O3 (1) (wherein, A is at least one element selected from Na or K, RE is at least one element selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Gd, Dy and Er, TM is at least one element selected from the group consisting of V, Nb and Ta, w, x, y, z and m satisfy the following relationships of (2)˜(5), 0.007?x?0.125 (2), x<y?2.0x (3), 0?(w+z)?0.01 (4), 0.94?m?0.999 (5)). And the semiconductor ceramic composition includes Ca in a proportion of 0.01˜0.055 mol in terms of element relative to 1 mol of Ti sites.

Abstract: A barium titanate based PTC thermistor ceramic composition without using Pb. Its Curie temperature is shifted to a temperature higher than 120° C. The PTC thermistor can readily turn semiconductive even if it is sintered in air. The resistivity at 25° C. is low and the variation rate of the resistivity at 25° C. with time is little. The PTC thermistor ceramic composition includes a sintered body having a barium titanate based compound represented by formula (1) as the main component, (Ba1-x-y-wBixAyREw)?(Ti1-zTMz)O3 (1), wherein, 1.02y?x?1.5y (2), 0.007?y?0.125 (3), 0?(w+z)?0.01 (4), 0.97???1.06 (5), and the sintered body contains Ca in a ratio of 0.01 mol or more and less than 0.05 mol relative to 1 mol of Ti site in terms of element.

Abstract: A semiconductor ceramic composition with small resistivity at room temperature and large temperature coefficient of resistance is provided; the composition is represented by formula, (Ba1-x-y-wBixAyREw)m(Ti1-zTMz)O3 ??(1), (wherein, A is at least one element from Na or K, RE is at least one element from the group consisting of Y, La, Ce, Pr, Nd, Sm, Gd, Dy and Er, TM is at least one element from the group consisting of V, Nb and Ta, and w, x, y, z (each in mol) and the mole ratio m of Ba site to Ti site satisfy the following in equations, 0.007?x?0.125 ??(2) x?y?2.0x ??(3) 0?(w+z)?0.010 ??(4) 0.940?m?0.999 ??(5)), and further includes Sr in a proportion of 0.010 mol or more and 0.050 mol or less relative to 1 mol of Ti site, and the mole ratio u of Sr and the mole ratio x of Bi satisfy the following in equation, u?1.8x?0.008 ??(6).

Abstract: A composite piezoelectric ceramic includes a compact of crystal particles including at least one of potassium niobate (KNbO3) and sodium niobate (NaNbO3) and optionally further including lithium niobate (LiNbO3), and a layer containing barium titanate (BaTiO3) that is disposed on the surface of the compact while forming a heterojunction with the compact. A piezoelectric device includes the composite piezoelectric ceramic.

Abstract: A semiconductor ceramic composition which includes a compound represented by the following formula (1) as a main component, (Ba1-x-y-wBixAyREw)m(Ti1-zTMz)O3 (1) (wherein, A is at least one element selected from Na or K, RE is at least one element selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Gd, Dy and Er, TM is at least one element selected from the group consisting of V, Nb and Ta, w, x, y, z and m satisfy the following relationships of (2)˜(5), 0.007?x?0.125 (2), x<y?2.0x (3), 0?(w+z)?0.01 (4), 0.94?m?0.999 (5)). And the semiconductor ceramic composition includes Ca in a proportion of 0.01˜0.055 mol in terms of element relative to 1 mol of Ti sites.