| 摘要 |
PROBLEM TO BE SOLVED: To obtain a high relative permittivity εr and a high Q value in a high frequency region. SOLUTION: This dielectric ceramic composition contains at least a rare earth element (Ln), Al, M (M is at least one or more of Ca and Sr), Ba and Ti as metallic elements and (a), (b), (c), (d), (e) and (x) are within the ranges of 0.056<=(a)<=0.450, 0.056<=(b)<=0.450, 0.100<=(c)<=0.500, 0<(d)<=0.100, 0.100<e<0.470 and 3<=(x)<=4 with the proviso that 0.75<=(b/a)<=1.25, 0.75<= e/[(c)+(d)]}<=1.25 and [(a)+(b)+(c)+(d)+(e)]=1 when the compositional formula according to the molar ratios of the metallic elements is represented by aLn2 Ox .bAl2 O3 .cMnO.dBaO.eTiO2 and has >=95% relative density, <=5% porosity and 1-30 μm average crystal grain diameter. Furthermore, the composition contains α-Al2 O3 as a crystal phase. |
