Influence of rare earth ion doping on the dielectric properties of CaTiO3-SmAlO3 ceramics

Rare earth ion (Nd, Sm, La and Ce) doped CaTiO3-SmAlO3 ceramics were obtained from corresponding oxides by thermal decomposition method and sintering at different temperatures up to 1370?C. The microstructure, densification and dielectric properties were systematically studied. The relationship between microstructure and dielectric properties was also correlated to understand the key contributor which improves quality factor. Relative dielectric constant of ?r ? 39.3 and the highest quality factor Q ? f = 49430GHz with small temperature coefficient ?f of ?9.4 ppm/K were obtained for the CaTiO3-Sm0.85Nd0.15AlO3 sample doped with 1.5 at.% Ce.